DTrack2 User Manual V2.12.0 ART DTrack 2.12

User Manual: ART DTrack User Manual 2.12

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Terms and definitions
Safety
- Symbols and their meaning
- Safety warnings
Introduction
Markers and targets (rigid bodies)
System setup
Interaction devices
Frequently asked questions (FAQ)
General Information
Technical specifications
Technical Appendix
- Definition of Coordinates and Rotations
- Output of Measurement Data via Ethernet
List of Figures
List of Tables
Index

version 2.12

April 2016

2016 A.R.T. GmbH

Contents are subject to

change without notice

weisser Text als Fake ...

System user manual

ARTtrack R

, TRACKPACK & DTrack R



dasbetrifft die gesamte seitenbreite der seite des dokumentes etetcetcetcetcetcetcetc etcetcetcetc

Trademarks

The following overview shows the registered trademarks of A.R.T. GmbH (Advanced Re-

altime Tracking GmbH):

trademarks illustrated as in Germany in the EU in the USA

A.R.T. R

ART ×××

ARTtrack R

ARTTRACK ×××

DTrack R

DTrack2 ×

smARTtrack R

SMARTTRACK ×××

×××

Microsoft R

and Windows R

are trademarks registered in the United States and

other countries by the Microsoft Corporation.

The company names and product names written in this manual are trademarks

or registered trademarks of the respective companies.

License agreement

The license provider guarantees the license holder a personal right to use the

DTrack2 software. A single license entitles the license holder to use the

software on all computers and networks of the license holder’s

branch/subsidiary ofﬁce.

In no event shall ART GmbH be liable for any incidental, indirect, or

consequential damages whatsoever (including, without limitation, damages for

loss of business proﬁts, business interruption, loss of business information, or

any other pecuniary loss) arising out of the use of or inability to use the software

or hardware.

1999 - 2016 by ART GmbH

Am Öferl 6

D-82362 Weilheim i. OB

Germany

T+49 (0)881-92530-00

v+49 (0)881-92530-01

http://www.ar-tracking.de

What’s new in version v2.12?

Following, a short overview of the main new features in DTrack2 version v2.12:

•Easier addition of cameras: To add a camera, simply re-calibrate the room with-

out losing the origin and orientation of the original coordinate system and continue

tracking. A similar procedure applies when removing cameras from the system.

•Integration of ’COOTrans’, our co-ordinate adjustment utility. This means that the

room adjustment can now be used to transform the tracking coordinate system

into the coordinate system of speciﬁc 3rd party objects, provided that the reference

points are known and can be measured (license-based)

•Support of bodies with up to 30 markers each

•Support of bodies with visibility restrictions including display of emission cones

within ’Body Adjustment’

•Additional information dialog regarding cylindrical markers within ’Body Calibration

Result Dialog’

•New function to remove unused markers from a rigid body within ’Body Adjustment’

•Radio channel settings are saved persistently when choosing a speciﬁc channel

number

What’s new in version v2.11?

Following, a short overview of the main new features in DTrack2 version v2.11:

•Support of new TRACKPACK/E cameras with Controllers including Synccard3 (see

e.g. chapter 4.1.3 on page 31)

•Support of new ARTTRACK5/C cameras for cave installations with Controllers in-

cluding Synccard3 (see e.g. chapter 4.1.2 on page 28)

•Improvements of usability of Hybrid Motion Capture (see chapter 4.4 on page 63)

What’s new in version v2.10?

Following, a short overview of the main new features in DTrack2 version v2.10:

•Support of ARTTRACK5 cameras with Controllers including Synccard3 (see e.g.

chapter 4.1.1 on page 25)

•Support of external sync source ’TTL signal, both edges’ (see e.g. chapter 4.5.6.3

on page 101)

•New license model. (see e.g. table 4.3 on page 76)

Contents

Termsanddeﬁnitions ................................. 9

1 Safety 11

1.1 Symbols and their meaning . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

1.2 Safetywarnings ................................. 11

2 Introduction 14

3 Markers and targets (rigid bodies) 16

3.1 Passivemarkers ................................. 16

3.2 Activemarkers .................................. 17

3.3 Standardtargets ................................. 20

4 System setup 25

4.1 The tracking cameras of ART .......................... 25

4.1.1 ARTTRACK5 .............................. 25

4.1.2 ARTTRACK5/C ............................. 28

4.1.3 TRACKPACK/E ............................. 31

4.1.4 ARTTRACK2 (discontinued) ...................... 33

4.1.5 ARTTRACK3 (discontinued) ...................... 35

4.1.6 TRACKPACK (discontinued) ...................... 38

4.1.7 TRACKPACK/C (discontinued)..................... 40

4.2 The Controllers of ART ............................. 43

4.2.1 Installation of the ART Controller (DTrack2 since v2.10) . . . . . . . 44

4.2.2 Installation of the ARTTRACK Controller (discontinued) . . . . . . . 48

4.2.3 Installation of the TRACKPACK Controller (discontinued) . . . . . . 52

4.2.4 Setting a static IP address without the DTrack2 Frontend (available

from controller software version v2.2) . . . . . . . . . . . . . . . . . 54

4.2.5 Thesetupﬁle............................... 55

4.2.6 The information ﬁle . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56

4.2.7 WakeOnLAN .............................. 56

4.2.8 Remote command strings . . . . . . . . . . . . . . . . . . . . . . . . 58

4.3 Setting up cascaded systems . . . . . . . . . . . . . . . . . . . . . . . . . . 58

4.4 Setting up the Hybrid Motion Capture System . . . . . . . . . . . . . . . . 63

4.5 DTrack2 frontendsoftware ........................... 70

4.5.1 Gettingstarted .............................. 70

4.5.1.1 Installation guide (Windows) . . . . . . . . . . . . . . . . . 70

4.5.1.2 Installation guide (Linux) . . . . . . . . . . . . . . . . . . . 71

4.5.1.3 Software update . . . . . . . . . . . . . . . . . . . . . . . . 72

4.5.1.4 Start DTrack2 frontend software . . . . . . . . . . . . . . . 72

4.5.1.5 Connecting to the controller . . . . . . . . . . . . . . . . . . 72

4.5.1.6 Adjustment of the cameras . . . . . . . . . . . . . . . . . . 74

4.5.1.7 Localizing and removing of disturbing reﬂections . . . . . . 76

4.5.2 Roomcalibration............................. 77

4.5.2.1 Room re-calibration . . . . . . . . . . . . . . . . . . . . . . 82

4.5.3 Bodycalibration ............................. 84

4.5.3.1 Selecting the coordinate system for 6DOF targets . . . . . 85

4.5.3.2 Calibration with a calibration ﬁle . . . . . . . . . . . . . . . 87

4.5.3.3 Body re-calibration . . . . . . . . . . . . . . . . . . . . . . 88

4.5.3.4 Target Library . . . . . . . . . . . . . . . . . . . . . . . . . 89

4.5.4 Bodyadjustment............................. 90

4.5.5 Filtering options in DTrack2 ...................... 91

4.5.6 Menustructure.............................. 93

4.5.6.1 Overview............................ 93

4.5.6.2 MenuDTrack2 ......................... 94

4.5.6.3 Menu Settings . . . . . . . . . . . . . . . . . . . . . . . . . 97

4.5.6.4 Menu Calibration . . . . . . . . . . . . . . . . . . . . . . . . 111

4.5.6.5 Menu Display . . . . . . . . . . . . . . . . . . . . . . . . . 120

4.5.6.6 MenuTools...........................124

4.5.6.7 MenuAbout ..........................124

5 Interaction devices 126

5.1 Flystick2......................................126

5.2 Flystick3......................................132

5.3 Fingertracking ..................................137

5.4 MeasurementTool ................................144

6 Frequently asked questions (FAQ) 147

6.1 Backup ......................................147

6.2 Cameras .....................................147

6.3 Controller .....................................150

6.4 Synchronization .................................150

6.5 DTrack2 andshutterglasses ..........................157

6.6 DTrack2 andinterfaces .............................157

6.7 Software DTrack2 ................................158

6.8 Calibration ....................................161

6.9 Tracking......................................166

6.10Flystick ......................................167

6.11Fingertracking ..................................169

6.12MeasurementTool ................................171

6.13ActiveTargets...................................171

6.14 ART trackingand3DTVs ............................172

6.15 Radio transceivers used in ART products ...................172

7 General Information 173

7.1 Service ......................................173

7.2 Cleaning of the equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . 173

7.3 Warranty and liability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 173

7.4 Declaration of conformity . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175

A Technical speciﬁcations 190

A.1 Cameras .....................................190

A.1.1 ARTTRACK5 ..............................190

A.1.2 ARTTRACK5/C .............................191

A.1.3 TRACKPACK/E .............................192

A.1.4 ARTTRACK cameras (discontinued) . . . . . . . . . . . . . . . . . . 193

A.1.5 TRACKPACK cameras (discontinued) . . . . . . . . . . . . . . . . . 194

A.2 Flysticks......................................195

A.3 Fingertracking ..................................196

A.4 ARTController ..................................196

A.5 Overallsystem ..................................197

A.6 Systemlatency..................................199

B Technical Appendix 203

B.1 Deﬁnition of Coordinates and Rotations . . . . . . . . . . . . . . . . . . . . 203

B.1.1 RoomCalibration.............................203

B.1.1.1 Room Adjustment . . . . . . . . . . . . . . . . . . . . . . . 203

B.1.2 BodyCalibration .............................204

B.1.2.1 Deﬁnition of the Coordinates by the Body itself . . . . . . . 204

B.1.2.2 Deﬁnition of the Coordinates by the Room Coordinate Sys-

tem, with Origin in the Center of the Markers . . . . . . . . 204

B.1.2.3 Deﬁnition of the Coordinates by the Room Coordinate Sys-

tem, with Origin in a Marker . . . . . . . . . . . . . . . . . . 204

B.1.2.4 Coordinate System Deﬁnition for 5DOF Targets (with and

without cylinder markers) . . . . . . . . . . . . . . . . . . . 205

B.1.2.5 Coordinate System Deﬁnition for two 5DOF Targets with

cylindermarkers........................205

B.1.3 6DOFResults ..............................205

B.1.4 3DOFData ................................206

B.1.5 Flystickdevices..............................206

B.1.5.1 Flystick1 ............................206

B.1.5.2 Flystick2 ............................207

B.1.5.3 Flystick3 ............................208

B.1.6 Measurement Tools . . . . . . . . . . . . . . . . . . . . . . . . . . . 208

B.1.6.1 Orientation of a Measurement Tool . . . . . . . . . . . . . 208

B.1.6.2 Using a reference body . . . . . . . . . . . . . . . . . . . . 208

B.1.7 Fingertracking ..............................209

B.2 Output of Measurement Data via Ethernet . . . . . . . . . . . . . . . . . . . 210

B.2.1 FrameCounter..............................211

B.2.2 Timestamp ................................211

B.2.3 Standard 6DOF Bodies . . . . . . . . . . . . . . . . . . . . . . . . . 211

B.2.4 Standard 6DOF Bodies (extended format) . . . . . . . . . . . . . . . 212

B.2.5 Flysticks..................................213

B.2.6 Flysticks (Old Format) . . . . . . . . . . . . . . . . . . . . . . . . . . 214

B.2.7 Measurement Tools with sphere tip . . . . . . . . . . . . . . . . . . . 215

B.2.8 Measurement Tool references . . . . . . . . . . . . . . . . . . . . . . 216

B.2.9 Measurement Tools (Old Format) . . . . . . . . . . . . . . . . . . . . 216

B.2.10Fingertracking ..............................217

B.2.11 Additional 3DOF Markers . . . . . . . . . . . . . . . . . . . . . . . . 218

B.2.12 Additional Informations . . . . . . . . . . . . . . . . . . . . . . . . . 218

List of Figures 220

List of Tables 222

Index 223

Chapter 0

Terms and deﬁnitions

term deﬁnition

3DOF three degrees of freedom (i.e. only position)

6DOF six degrees of freedom (i.e. position and orientation)

5DOF ﬁve degrees of freedom (i.e. one degree less in orientation)

ART Controller calculates tracking data and generates the data output stream

(compatible to ARTTRACK2 ,ARTTRACK3 ,ARTTRACK5 ,

ARTTRACK5/C ,TRACKPACK/E )

ARTTRACK Controller (discontin-

ued)

calculates tracking data and generates the data output stream

(compatible to ARTTRACK1 ,ARTTRACK2 ,ARTTRACK3 )

ARTTRACK 2 & 3 (discontinued) infrared camera

ARTTRACK5 infrared camera

ARTTRACK5/C infrared camera dedicated for multi-sided projections

body calibration teach the system the geometry of a rigid body

body, rigid body rigid arrangement of several single markers (see also "target")

calibration angle (410mm or 710mm) belongs to the room calibration set and deﬁnes origin and orien-

tation of the room coordinate system

ceiling suspension equipment to mount an infrared camera to the ceiling

DTrack2

backend software Linux-based software which does all necessary calculations

frontend software graphical user interface to control the controller

Field of View (FoV) is the area of interest captured on the cameraâ ˘

A´

Zs imager

ﬁnger thimble a ﬁxture for the ﬁnger tip to hold the active marker(s)

Fingertracking tracks the orientation of the hand and the position of the ﬁngers

Flystick wireless interaction device for virtual reality (VR) applications

hand geometry describes the dimensions of your hand and ﬁngers

hybrid tracking fusion of optical and inertial data into one consolidated output

inertial sensor an inertial measurement unit simultaneously measures 9 phys-

ical properties, namely angular rates, linear accelerations, and

magnetic ﬁeld components (not used) along all 3 axes. This is

achieved using solid state gyroscopes for measurement of roll,

pitch and yaw and accelerometers for drift correction.

infrared optical tracking position measurement of bodies (subjects or objects) based

upon infrared light and optical measurement procedures

license code (license key) software key to unlock certain capabilities of the tracking system

marker object either made of retro reﬂective material or LED for position

tracking (3DOF)

Measurement Tool a pointing device which allows to measure the position of the

tool’s tip with high accuracy

measurement volume deﬁnes the volume where optical tracking is possible

modulated ﬂash infrared signal which is used for wireless synchronization

motion capture track movements of a human body

mutual blinding one camera sees disturbing reﬂections caused by the infrared

ﬂashes of another one

prediction predicts output for the speciﬁed time in the future to compensate

tracking and rendering latency

room calibration teach the system the position of each camera and deﬁne origin

and orientation of the room coordinate system

room calibration set consists of angle and wand

syncgroup cameras being in one syncgroup receive the sync signal at the

same time. Syncgroups are distinguished by a short time delay

between their sync signals (i.e. mutual blinding may be avoided).

synccard (Synccard2/3 or Sync-

cardTP)

plug-in card for the controller which serves for synchronizing the

cameras

term deﬁnition

Tactile Feedback system for ﬁnger-based interactions in immersive virtual reality

applications (wires touch the inside of the ﬁnger tips and provide

an impression when they are shortened)

target rigid arrangement of several single markers ( = rigid body)

tracking position measurement of bodies that move in a deﬁned space

TRACKPACK (discontinued) infrared camera

TRACKPACK/C (discontinued) infrared camera dedicated for multi-sided projections

TRACKPACK/E infrared camera

TRACKPACK Controller (discontin-

ued)

calculates tracking data and generates the data output stream

(compatible to TRACKPACK and TRACKPACK/C )

USB radio transceiver (RT2, RT3) exchange data with Flystick or Tactile Feedback

virtual point cloud used for calculating the relative positions of the IR cameras

wand precalibrated stick carrying two markers. The wand belongs to

the room calibration set and is used to generate a virtual point

cloud and to scale the system

Chapter 1

1 Safety

1.1 Symbols and their meaning

You can ﬁnd the following symbols and their signiﬁcation on the equipment or in the man-

ual:

iUseful and important notes.

ZImportant notes, which may lead to system malfunction or to the

loss of warranty by non-observance.

Important safety warning to assure operation safety.

These warnings have to be considered, otherwise user

and equipment could be endangered, the equipment could be

damaged or the function of the equipment is not warranted.

Safety warning for infrared radiation.

These warnings have to be considered, otherwise users eyes

could be endangered.

Table 1.1: Symbols and their meaning

1.2 Safety warnings

ZSafe operation of the equipment is only warranted if the warnings in

this manual and on the equipment are observed.

•Never use the equipment if any part looks damaged.

•Safe operation is not possible, if

–the housing is damaged,

–any ﬂuid attains in the housing,

–objects attain inside the equipment,

–the equipment shows any visible faults (smoke, sparks, ﬁre, smells, etc.) or

–the power cord is damaged.

•In any of the cases mentioned above (or similar) pull the power cord out of the power

1 Safety

socket immediately. Otherwise, users or environment are endangered. Please con-

tact the ART service.

•Never change or alter the equipment, neither mechanically nor electrically. Only the

components described by ART shall be used. The conformity and the warranty of

the producer (ART ) expire by non-compliance.

•Never open the equipment! Only personnel authorized by ART is allowed to open

the equipment. Inside of the equipment there are various hazards like high voltage,

electric shocks - even if the equipment is disconnected - which can lead to death on

contact. In case of malfunction of the equipment please contact the ART service.

•Only peripheral devices which meet the safety requirements of EN/IEC 60950 for

extra low voltage may be attached on Ethernet-, BNC- and the DC-circuit of the

equipment.

•The cameras emit infrared light. Keep a distance of min. 20 cm when operating the

cameras. All cameras are assigned to the Exempt Group according to IEC62471-1

and therefore pose no risk or hazard to the human eye or skin at this distance.

•Be sure that the cameras are ﬁrmly mounted in the correct position.

•Do not touch the front pane of the cameras, since the acrylic pane and the lens are

highly sensitive surfaces. Be careful to avoid permanent damages (e.g. scratches).

Only touch the housings of the cameras.

•The ventilation holes of the ARTTRACK2 camera must not be covered. Air circu-

lation is necessary to prevent the cameras from overheating. If the air circulation

is restricted overheating will damage the cameras. The minimum distance between

equipment and environmental objects has to be greater than 3 cm.

•The equipment has to be attached to a power socket with grounding. If the ground-

ing wire is defective the requirement of the safety and the electromagnetic compat-

ibility (EMC) are not guaranteed. To check the function of the grounding wire ask

your regional located electrician.

•Before switching on any device, verify that voltage and frequency of your electric

installation are within the allowed ranges of the equipment. The characteristics of

the equipment can be found on the appliance rating plate or in chapter A on page

190. The appliance rating plates are on the equipment’s housing (ARTTRACK1 on

the lower side of the housing; ARTTRACK2 /ARTTRACK3 on external power sup-

ply, ARTTRACK5 &ARTTRACK5/C /TRACKPACK/E on camera housing, all con-

trollers on the backside of the housing).

•The power switch on the backside does not completely separate the devices from

the electricity network. To completely separate the equipment from the electricity

network the power plug must be disconnected from the power socket. The power

plug has to be accessible freely. The power socket must be close to the equipment.

Chapter 1

1.2 Safety warnings

•Please install the cables such that

–no one can stumble over the cords,

–the cords cannot be damaged,

–the cords cannot damage the cameras due to mechanical strain,

–the line of sight of the cameras is not obstructed.

Install a strain relief!

•Only use original ART (or ART authorized) components and accessories. Using

non-original components or accessories may damage the equipment, cause mal-

functions or may void operation safety. The provided components and original

accessories can be found in chapters 4 on page 25 and 5 on page 126. Only

use the originally provided external power supply for operating the camera ART-

TRACK2 and ARTTRACK3 and, if applicable, only the provided PoE+ switch for

ARTTRACK5 &ARTTRACK5/C .

•The equipment must not be dropped and/or knocked.

•Do not use any solvents or water to clean the cameras. For more information about

cleaning the cameras please read chapter 7.2 on page 173.

•Never expose the equipment to high levels of humidity or condensating humidity.

Protect the cameras against water and chemicals.

•The equipment must not be operated in environments with intensive formation of

dust or hot environments where temperatures rise above 40◦C (100◦F).

ZART explicitly denies any liability or warranty if the product is modiﬁed

in any way or not used according to this manual and the speciﬁcation

labels on the equipment.

2 Introduction

ART tracking systems are infrared (IR) optical tracking systems. In this user manual we

are going to perceive "tracking" as measurement of the position of objects or subjects that

move in a deﬁned space. These objects or subjects to be tracked have to be equipped

with single markers or rigid arrangements of markers (= rigid body or target).

Position and/or orientation of those rigid bodies can be measured. If only the spatial po-

sition (X, Y, Z) is measured we call this "three degrees of freedom" (3DOF) tracking. The

simultaneous measurement of position and orientation (three independent angular coor-

dinates) is called "six degrees of freedom" (6DOF) tracking.

Single markers are sufﬁcient if only 3DOF coordinates are needed. For 6DOF tracking, a

rigid body is mandatory.

Passive markers are covered with retro reﬂective material - they act as light reﬂectors.

Active light emitters (i.e. based on infrared LEDs) are called active markers (see chapter

3 on page 16).

Figure 2.1: Principle of optical tracking (stereo vision)

Figure 2.1 shows the principle of infrared optical tracking with a two-camera system and

a standard target.

Chapter 2

The cameras are sending out synchronized IR ﬂashes which are reﬂected towards the

lens by the retro reﬂective material which is covering the markers of the target. Intelligent

tracking cameras, that are scanning a certain volume, detect the IR radiation that is re-

ﬂected by the markers and create a greyscale image based on the received IR radiation.

During the preprocessing the camera calculates the 2D marker positions with high accu-

racy using pattern recognition. A mean 2D-accuracy of 0.04 pixels (0.1 pixels maximum

2D-deviation) is standard in ART tracking cameras. Then, the 2D data are being sent to

the Controller via Ethernet.

Now, the controller has to calculate 3DOF or 6DOF data. The base for this calculation

is that the cameras’ ﬁeld of views are overlapping. DTrack2 calculates the path of the

optical rays from the cameras to the markers and delivers the ray intersections in three-

dimensional coordinates. These intersections are the positions of the markers.

The position and orientation of the cameras are known from the room calibration. During

body calibration, DTrack2 identiﬁes certain marker arrangements as rigid bodies. Based

upon this, DTrack2 is able to calculate 6DOF data and, ﬁnally, knows position and orien-

tation of the target and, therefore, of the object or subject to be tracked.

In optical tracking systems you have to be aware that tracking is only possible as long as

the target is positioned in tracking range of the cameras and is not occluded by any other

objects or the object to be tracked. More in detail, at least four markers of a target have

to be visible for a minimum of two cameras to enable tracking.

3 Markers and targets (rigid bodies)

3.1 Passive markers

The passive markers used in ART tracking systems are retro reﬂectors. These markers

reﬂect the incoming IR radiation into the direction of the incoming light. More precise: the

IR radiation is reﬂected into a narrow range of angles around the (opposite) direction of

the incoming light. Passive markers can be either

1. spherical markers:

+ excellent visibility from any perspective,

- expensive fabrication,

- sensitive surface,

- target requires larger volume →danger of mechanical damage.

2. ﬂat markers:

+ cheap,

+ ﬂat targets possible,

+ robust surface because cover may be applied,

- the angular range of visibility is limited to approx. ±45◦.

3. ring markers:

+ cheap,

+ cylindrically shaped targets possible,

+ robust surface,

- the angular range of visibility is limited to approx. ±45◦.

Passive markers are mostly spheres covered with retro reﬂecting foils. However, they can

also be stickers made from retro reﬂecting material.

Retro reﬂecting sheets or foils available on the market can be based on two different op-

tical principles:

Chapter 3

3.2 Active markers

1. Triple mirrors, which are arranged such that their planes

form angles of 90◦by pairs, are reﬂecting light in the de-

scribed way. Mostly foils with arrangements of many very

small mirrors in a plane are used.

2. Glass spheres (with a proper refraction index) are fo-

cussing incoming light approximately to the opposite sur-

face of the ball. A layer of microscopic glass spheres, car-

ried by a reﬂecting material, acts as a retro reﬂector. These

foils can be fabricated on a ﬂexible carrier material, thus

they are widely used for equipping spherical markers with

retro reﬂecting surfaces.

iART spherical markers are covered with retro reﬂecting foils, based on

the glass spheres principle.

ZThe quality of the markers decreases when they are in contact with

dust, dirt, fat, liquids, glue or comparable contaminants. Please make

sure that the markers are not touched or damaged.

3.2 Active markers

Basics Active markers are light (i.e. infrared light) emitting elements, mostly LEDs.

In ART tracking systems four types of LED-based active markers may be used, depend-

ing on the application:

1. Single LEDs without diffusor sphere:

+ can be covered with acrylic protection ﬁlm,

+ results in simple and robust markers providing visibility up

to high distances (up to 10m),

- the angular range of visibility is limited to approx. ±60◦.

3 Markers and targets (rigid bodies)

2. Single LEDs with diffusor sphere:

+ for optimum angular range of visibility,

- distance between marker and tracking camera is limited to

a short distance (up to 4.5m).

3. Big active spherical markers:

+ several single LEDs per marker, covered with light scatter-

ing spheres,

+ provide visibility from all sides and up to very high distances

(approx. 20m),

+ suitable for outdoor tracking,

- diameter: 50mm,

- weight: 50g.

4. Big active ﬂat markers:

+ several single LEDs per marker, covered with light scatter-

ing surface,

+ tracking up to very high distances (approx. 20m),

+ suitable for outdoor tracking,

+ magnetic base for easy positioning on metal surfaces,

- the angular range of visibility is limited to less than 180◦,

- diameter: 30mm.

All active markers provided by ART are controlled by a special PC board and need power

supply.

Synchronization of active markers Active markers could in principle be activated in

CW mode (i.e. continuous light emission). However, this would not be very clever be-

cause tracking cameras have a very narrow time slot of sensitivity, i.e. most of the light

emitted by the markers would be useless for tracking. As a consequence, maximum dis-

tance between cameras and marker would be very short due to an upper limit of power

dissipation allowed for each single LED. Therefore, all active markers provided by ART are

emitting radiation only when the tracking cameras are sensitive, thus having to be syn-

chronized with the cameras.

Synchronization can be done by a wired connection between the tracking system and the

pc-board controlling the active markers, but can also be done in a wireless way.

Chapter 3

3.2 Active markers

(a) Single LED (b) Single LED with diffusor sphere

Figure 3.1: Angular range of visibility

For wireless synchronization a coded IR ﬂash is being sent out by a tracking camera. The

active marker’s PC board recognizes the coded ﬂash and activates the LEDs.

3 Markers and targets (rigid bodies)

3.3 Standard targets

Type Description Weight approx. Dimension Marker

size

Hand target The hand target is designed for hand track-

ing in usability and assembly studies re-

spectively. It is also frequently used as a

small general-purpose target. Due to the

small size this target is easily occluded by

the hand carrying it. Therefore, proper ar-

rangement of tracking cameras has to be

used in order to avoid occlusions.

25g / 0.9oz (110 ×80 ×28)mm 12mm

Large hand target This hand target is designed for hand track-

ing in a two camera tracking system. Its

large size allows to move the hand in al-

most all directions, without losing tracking.

30g / 1.1oz (170 ×120 ×35)mm 12mm

Claw target The claw target looks just the same as the

hand target. But it comes in a bigger size

and is equipped with bigger markers.

35g / 1.2oz (160 ×110 ×30)mm 16mm

Chapter 3

3.3 Standard targets

Type Description Weight approx. Dimension Marker

size

Tree target Originally designed for tracking HMDs, the

tree target is a general-purpose target

for tracking from longer distances. It is

equipped with 20mm markers.

75g / 2.65oz (195 ×170 ×120)mm 20mm

Generic glasses target For head tracking mostly in passive stereo

systems, tracking targets must be ﬁxed to

the stereo glasses. ART offers several

light-weight standard targets for this pur-

pose.

min:

14g / 0.5oz

max:

22g / 0.7oz

(270 ×120 ×35)mm 12mm

INFITEC PREMIUM target Target tailored to the INFITEC PREMIUM

passive stereo glasses.

26g / 0.9oz (225 ×85 ×80)mm 12mm

3 Markers and targets (rigid bodies)

Type Description Weight approx. Dimension Marker

size

CrystalEyes R

2/3 target Target tailored to the shutter glasses of the

StereoGraphics active stereo system. It ﬁts

to both CrystalEyes R

2 and 3.

28g / 1oz (215 ×120 ×60)mm 12mm

CrystalEyes R

5 target Target tailored to the shutter glasses of the

StereoGraphics active stereo system. It ﬁts

to the CrystalEyes R

5.

19g / 0.7oz (195 ×105 ×40)mm 12mm

NuVision APG6000

and APG6100 target

Target tailored to the NuVision APG6000

and APG6100 shutter glasses.

17g / 0.6 oz (220 ×125 ×75)mm 12mm

Chapter 3

3.3 Standard targets

Type Description Weight approx. Dimension Marker

size

Volfoni EDGE R

target Target tailored to the Volfoni EDGE R

shut-

ter glasses.

23g / 0.7 oz (230 ×95 ×60)mm 12mm

NVIDIA 3D Vision R

Pro

target

Target tailored to the NVidia 3D Vision Pro

shutter glasses.

25g / 0.9 oz (225 ×100 ×60)mm 12mm

NVisor SX 60 target Target tailored to the NVisor SX 60 head

mounted display.

55g / 1.94oz (300 ×215 ×35)mm 12mm

3 Markers and targets (rigid bodies)

Type Description Weight approx. Dimension Marker

size

Motion capture targets ART provides a complete set of targets for

motion capture purposes. All targets are

6DOF targets and can be identiﬁed by the

tracking system. A full ART MoCap target

set consists of (subsets can be generated):

1 Glasses target (AGT4) 28g / 1.0oz (225 ×180 ×95)mm 12mm

2 Shoulder targets (UT) 44g / 1.55oz (90 ×75 ×35)mm 12mm

1 Dorsal target (DT) 84g / 2.96oz (150 ×65 ×35)mm 12mm

2 Upper arm targets (HBT) 52g / 1.83oz (150 ×70 ×35)mm 12mm

2 Forearm targets (UBT) 50g / 1.76oz (150 ×65 ×35)mm 12mm

2 Hand targets (HT) 25g / 0.9oz (110 ×80 ×28)mm 12mm

1 Waist target (WT, one-piece) 195g / 6.9oz (390 ×140 ×50)mm 14mm

1 Waist target (WT, multi-part), each 30g / 1.1oz (90 ×60 ×50)mm 16mm

2 Upper leg targets (FBT) 99g / 3.49oz (220 ×120 ×40)mm 16mm

2 Lower leg targets (TBT) 58g / 2.05oz (205 ×70 ×35)mm 16mm

2 Foot targets (FT) 65g / 2.29oz (95 ×105 ×70)mm 16mm

Table 3.3: Standard targets overview

Chapter 4

4 System setup

4.1 The tracking cameras of ART

4.1.1 ARTTRACK5

Keep a distance of min. 20 cm when operating the camera ! The

camera is assigned to the Exempt Group according to IEC62471-1 and

therefore poses no risk or hazard to the human eye or skin at this dis-

tance.

Description The ARTTRACK5 infrared camera is intended for working environments

with distances between camera and markers of up to 7.5 metres. By default the ART-

TRACK5 is equipped with a 3.5 mm lens. Depending on the application and the setup the

ARTTRACK5 can be equipped with other lenses (i.e. with different focal lengths). Refer

to A.1 on page 190 for a list of available focal lengths and the respective FoV.

Figure 4.1: Camera ARTTRACK5

Mounting The ARTTRACK5 cameras are optimized for a predeﬁned range of measure-

ment volumes. System operation in smaller or bigger measurement volumes can lead

4 System setup

to reduced accuracy or other malfunctions. The measurement volume can be adjusted

within certain limits simply by changing the ﬂash intensity of the ART infrared cameras

(see chapter 4.5.6.3 on page 97).

iThe ﬂash intensities should not be too high. In general, a ﬂash inten-

sity of 50-60 might be sufﬁcient.

Major changes of the measurement volume may require different lenses and thus a new

determination of camera parameters. These changes have to be done at the ART labs.

Be aware that a tracking system is very sensitive to camera movements. Therefore, the

cameras have to be mounted in a way that reduces camera movements (especially vibra-

tions) as much as possible.

iMounting on tripods may be sufﬁcient for presentations and prelimi-

nary installations, but is not recommended as a ﬁnal solution!

If you want to mount the camera on a tripod there’s no carrier needed.

Otherwise the carrier for the ARTTRACK5 can be attached on both bottom and top side

of the camera. Attach the carrier with the T-piece pointing to the back of the camera as

shown in ﬁgure 4.2 on page 26. Note, the ceiling suspension is already connected to the

carrier in ﬁgure 4.2.

Figure 4.2: Attaching the ceiling mount to the ARTTRACK5 camera

Chapter 4

4.1 The tracking cameras of ART

Figure 4.3: Mounting a camera to a wall or a ceiling (e.g. ARTTRACK2 camera)

Only use screws supplied with the ceiling mount for mounting it.

Also, use all the parts supplied with the ceiling mount - especially the

toothed washer is quite important.

You shall never open other screws on the cameras (see chapter 1.2

on page 11). Otherwise, the camera may be damaged and liability and

warranty is void.

Feel free to contact ART in case you want to realise a more complex installation. We will

assist you in your planning.

Make sure to install the system in a way that you can easily access the cameras and

its cables. Be especially careful to mount the cameras ﬁrmly so they cannot fall down.

Unsecured cameras may pose a serious hazard to health and safety.

Avoid hard shocks at all times! A new camera calibration at the ART fa-

cilities might become necessary in that case.

Figure 4.3 on page 27 shows the correct mounting for a camera to a wall with a carrier

using the example of an ARTTRACK2 camera. Make sure to not fall below minimal

distance to the wall so enough room is left for the cables and to allow readjustment of the

camera angles and maintenance.

Use strong dowels and screws for mounting the cameras to walls or ceilings (see ﬁgure

4.3 on page 27).

If in doubt, ask a skilled craftsman for assistance. Use massive and long enough angle

irons to provide the required stiffness and stability.

To avoid measurement problems, no light sources or highly reﬂecting areas should be

visible to the camera. Especially strong point light sources like e.g. halogen lamps and

direct or reﬂected sunlight may imply problems for the measurement (ﬂuorescent lamps

are ok).

Please install the cables such that

•no one can stumble over the cords,

4 System setup

•the cords cannot be damaged,

•the cords cannot damage the cameras due to mechanical strain,

•the line of sight of the cameras is not obstructed.

Inappropriate cabling may pose a serious hazard to health and safety.

Cable ducts or ﬁxings should be used and a strain relief should be

installed!

Please refer to chapter 4.2.2 on page 48 for more information.

4.1.2 ARTTRACK5/C

Keep a distance of min. 20 cm when operating the camera ! The

camera is assigned to the Exempt Group according to IEC62471-1 and

therefore poses no risk or hazard to the human eye or skin at this dis-

tance.

Description The ARTTRACK5 or TRACKPACK/E system may be combined with the

ARTTRACK5/C camera in order to realize tracking in multi-sided projection environments

(e.g. CAVE R

, I-Space). In such an environment it is necessary to drill holes into the pro-

jections’ corners as the camera cannot see through the screen. The ARTTRACK5/C cam-

era has been designed to easily ﬁt into such holes by separating the lens from the elec-

tronics part (see ﬁgure 4.4). With its 4.0 mm lens a large ﬁeld of view (FoV) is covered.

Refer to A.1 on page 190 for more information.

Figure 4.4: Camera ARTTRACK5/C

The 26-pin D-Sub connector between ARTTRACK5/C remote camera

head and camera body employs proprietary design. Do not try to con-

nect the remote head to any other port (e.g. COM port) !!!

Chapter 4

4.1 The tracking cameras of ART

The ARTTRACK5/C system either consists of ARTTRACK5/C cameras only or it can be

mixed with standard ARTTRACK5 or TRACKPACK/E cameras - both variants are limited

to a total number of 50 cameras per system.

Mounting The ARTTRACK5/C cameras are optimized for a predeﬁned range of mea-

surement volumes. System operation in smaller or bigger measurement volumes can lead

to reduced accuracy or other malfunctions. The measurement volume can be adjusted

within certain limits simply by changing the ﬂash intensity of the ART infrared cameras

(see chapter 4.5.6.3 on page 97).

iThe ﬂash intensities should not be too high. In general, a ﬂash inten-

sity of 50-60 might be sufﬁcient.

Major changes of the measurement volume may require different lenses and thus a new

determination of camera parameters. These changes have to be done at the ART labs.

Be aware that a tracking system is very sensitive to camera movements. Therefore, the

cameras have to be mounted in a way that reduces camera movements (especially vibra-

tions) as much as possible.

iMounting on tripods may be sufﬁcient for presentations and prelimi-

nary installations, but is not recommended as a ﬁnal solution!

If you want to mount the camera on a tripod just mount the carrier on any side of the

camera body and then the remote camera head on the opposite side using a ceiling

mount.

Otherwise the carrier for the ARTTRACK5/C can be attached on all 4 sides of the camera

body. Attach the carrier with the T-piece pointing to the back of the camera in a similar

way to ﬁgure 4.2 on page 26. Note, the ceiling suspension is already connected to the

carrier in ﬁgure 4.2. The ARTTRACK5/C remote camera head should be installed using

the M6 mounting threads on its back as shown in ﬁgure 4.5 on page 29.

Figure 4.5: Camera ARTTRACK5/C remote head (back)

4 System setup

ZThe ARTTRACK5/C remote head has to be connected to its corre-

sponding camera body. During mounting please ensure matching se-

rial numbers for both parts !

Only use screws supplied with the ceiling mount for mounting it. Do

not use standard screws for connection of the remote camera head

due to limited space between thread and cable. Also, use all the parts

supplied with the ceiling mount - especially the toothed washer is quite

important.

You shall never open other screws on the cameras (see chapter 1.2

on page 11). Otherwise, the camera may be damaged and liability and

warranty is void.

Feel free to contact ART in case you want to realise a more complex installation. We will

assist you in your planning.

Make sure to install the system in a way that you can easily access the cameras and

its cables. Be especially careful to mount the cameras ﬁrmly so they cannot fall down.

Unsecured cameras may pose a serious hazard to health and safety.

Avoid hard shocks at all times! A new camera calibration at the ART fa-

cilities might become necessary in that case.

Figure 4.3 on page 27 shows the correct mounting for a camera to a wall with a carrier

using the example of an ARTTRACK2 camera. Make sure to not fall below minimal

distance to the wall so enough room is left for the cables and to allow readjustment of the

camera angles and maintenance.

Use strong dowels and screws for mounting the cameras to walls or ceilings (see ﬁgure

4.3 on page 27).

If in doubt, ask a skilled craftsman for assistance. Use massive and long enough angle

irons to provide the required stiffness and stability.

To avoid measurement problems, no light sources or highly reﬂecting areas should be

visible to the camera. Especially strong point light sources like e.g. halogen lamps and

direct or reﬂected sunlight may imply problems for the measurement (ﬂuorescent lamps

are ok).

Please install the cables such that

•no one can stumble over the cords,

•the cords cannot be damaged,

•the cords cannot damage the cameras due to mechanical strain,

•the line of sight of the cameras is not obstructed.

Inappropriate cabling may pose a serious hazard to health and safety.

Cable ducts or ﬁxings should be used and a strain relief should be

installed!

Chapter 4

4.1 The tracking cameras of ART

Please refer to chapter 4.2.2 on page 48 for more information.

4.1.3 TRACKPACK/E

Keep a distance of min. 20 cm when operating the camera ! The

camera is assigned to the Exempt Group according to IEC62471-1 and

therefore poses no risk or hazard to the human eye or skin at this dis-

tance.

Description The TRACKPACK/E infrared camera is intended for working environments

with distances between camera and markers of up to 4.5 metres. With its 3.5 mm lens a

large ﬁeld of view (FoV) is covered. Refer to A.1 on page 190 for the respective FoV.

Figure 4.6: Camera TRACKPACK/E

Mounting The TRACKPACK/E cameras are optimized for a predeﬁned range of mea-

surement volumes. System operation in smaller or bigger measurement volumes can lead

to reduced accuracy or other malfunctions. The measurement volume can be adjusted

within certain limits simply by changing the ﬂash intensity of the ART infrared cameras

(see chapter 4.5.6.3 on page 97).

iThe ﬂash intensities should not be too high. In general, a ﬂash inten-

sity of 50-60 might be sufﬁcient.

Major changes of the measurement volume may require different lenses and thus a new

determination of camera parameters. These changes have to be done at the ART labs.

Be aware that a tracking system is very sensitive to camera movements. Therefore, the

cameras have to be mounted in a way that reduces camera movements (especially vibra-

4 System setup

tions) as much as possible.

iMounting on tripods may be sufﬁcient for presentations and prelimi-

nary installations, but is not recommended as a ﬁnal solution!

If you want to mount the camera on a tripod there’s no carrier needed.

Otherwise the carrier for the TRACKPACK/E can be attached on both bottom and top

side of the camera. Attach the carrier with the T-piece pointing to the back of the camera

in a similar way to ﬁgure 4.2 on page 26. Note, the ceiling suspension is already con-

nected to the carrier in ﬁgure 4.2.

Only use screws supplied with the ceiling mount for mounting it.

Also, use all the parts supplied with the ceiling mount - especially the

toothed washer is quite important.

You shall never open other screws on the cameras (see chapter 1.2

on page 11). Otherwise, the camera may be damaged and liability and

warranty is void.

Feel free to contact ART in case you want to realise a more complex installation. We will

assist you in your planning.

Make sure to install the system in a way that you can easily access the cameras and

its cables. Be especially careful to mount the cameras ﬁrmly so they cannot fall down.

Unsecured cameras may pose a serious hazard to health and safety.

Avoid hard shocks at all times! A new camera calibration at the ART fa-

cilities might become necessary in that case.

Figure 4.3 on page 27 shows the correct mounting for a camera to a wall with a carrier

using the example of an ARTTRACK2 camera. Make sure to not fall below minimal

distance to the wall so enough room is left for the cables and to allow readjustment of the

camera angles and maintenance.

Use strong dowels and screws for mounting the cameras to walls or ceilings (see ﬁgure

4.3 on page 27).

If in doubt, ask a skilled craftsman for assistance. Use massive and long enough angle

irons to provide the required stiffness and stability.

To avoid measurement problems, no light sources or highly reﬂecting areas should be

visible to the camera. Especially strong point light sources like e.g. halogen lamps and

direct or reﬂected sunlight may imply problems for the measurement (ﬂuorescent lamps

are ok).

Please install the cables such that

•no one can stumble over the cords,

•the cords cannot be damaged,

•the cords cannot damage the cameras due to mechanical strain,

Chapter 4

4.1 The tracking cameras of ART

•the line of sight of the cameras is not obstructed.

Inappropriate cabling may pose a serious hazard to health and safety.

Cable ducts or ﬁxings should be used and a strain relief should be

installed!

Please refer to chapter 4.2.2 on page 48 for more information.

4.1.4 ARTTRACK2 (discontinued)

Keep a distance of min. 20 cm when operating the camera ! The

camera is assigned to the Exempt Group according to IEC62471-1 and

therefore poses no risk or hazard to the human eye or skin at this dis-

tance.

Description The ARTTRACK2 infrared camera is intended for working environments

with distances between camera and markers of up to 4 metres. By default the ART-

TRACK2 is equipped with a 3.5 mm lens. Depending on the application and the setup the

ARTTRACK2 can be equipped with other lenses (i.e. with different focal lengths). Refer

to A.1 on page 190 for a list of available focal lengths and the respective FoV.

Figure 4.7: Camera ARTTRACK2

Mounting The ARTTRACK2 cameras are optimized for a predeﬁned range of measure-

ment volumes. System operation in smaller or bigger measurement volumes can lead

to reduced accuracy or other malfunctions. The measurement volume can be adjusted

within certain limits simply by changing the ﬂash intensity of the ART infrared cameras

4 System setup

(see chapter 4.5.6.3 on page 97).

iThe ﬂash intensities should not be too high. In general, a ﬂash inten-

sity of 3-4 might be sufﬁcient.

Major changes of the measurement volume may require different lenses and thus a new

determination of camera parameters. These changes have to be done at the ART labs.

Be aware that a tracking system is very sensitive to camera movements. Therefore, the

cameras have to be mounted in a way that reduces camera movements (especially vibra-

tions) as much as possible.

iMounting on tripods may be sufﬁcient for presentations and prelimi-

nary installations, but is not recommended as a ﬁnal solution!

If you want to mount the camera on a tripod just mount the carrier on the bottom of the

camera.

Otherwise the carrier for the ARTTRACK2 can be attached on both bottom and top side

of the camera. To attach the carrier remove the screws from the holes 1 and 2 and attach

the carrier with the T-piece pointing to the back of the camera in a similar way to ﬁgure 4.2

on page 26. Note, the ceiling suspension is already connected to the carrier in ﬁgure 4.2.

Only use screws supplied with the ceiling mount for mounting it. The

screws used for sealing the housings are not sufﬁciently long for ﬁxing

the carrier. Also, use all the parts supplied with the ceiling mount -

especially the toothed washer is quite important.

You shall never open other screws on the cameras (see chapter 1.2

on page 11). Otherwise, the camera may be damaged and liability and

warranty is void.

Feel free to contact ART in case you want to realise a more complex installation. We will

assist you in your planning.

It is recommended to install the power supply for the cameras in a way that enables the

switching of all cameras by one main switch. If this is done, the system can be easily

turned off and on without changing camera positions.

Make sure to install the system in a way that you can easily access the cameras and

its cables. Be especially careful to mount the cameras ﬁrmly so they cannot fall down.

Unsecured cameras may pose a serious hazard to health and safety.

Avoid hard shocks at all times! A new camera calibration at the ART fa-

cilities might become necessary in that case.

Figure 4.3 on page 27 shows the correct mounting for a camera to a wall with a carrier

using the example of an ARTTRACK2 camera. Make sure to not fall below minimal

distance to the wall so enough room is left for the cables and to allow readjustment of the

camera angles and maintenance.

Use strong dowels and screws for mounting the cameras to walls or ceilings (see ﬁgure

Chapter 4

4.1 The tracking cameras of ART

4.3 on page 27).

If in doubt, ask a skilled craftsman for assistance. Use massive and long enough angle

irons to provide the required stiffness and stability.

To avoid measurement problems, no light sources or highly reﬂecting areas should be

visible to the camera. Especially strong point light sources like e.g. halogen lamps and

direct or reﬂected sunlight may imply problems for the measurement (ﬂuorescent lamps

are ok).

Furthermore, please make sure the ventilator holes are not covered. For thermal rea-

sons the ventilator always has to be on the upper side of the ARTTRACK2 camera. That

means, if the camera is to be mounted hanging the carrier must be mounted on top (ven-

tilator side). If it is to be mounted standing the carrier has to be on the bottom side of the

housing.

Please install the cables such that

•no one can stumble over the cords,

•the cords cannot be damaged,

•the cords cannot damage the cameras due to mechanical strain,

•the line of sight of the cameras is not obstructed.

Inappropriate cabling may pose a serious hazard to health and safety.

Cable ducts or ﬁxings should be used and a strain relief should be

installed!

Please refer to chapter 4.2.2 on page 48 for more information.

4.1.5 ARTTRACK3 (discontinued)

Keep a distance of min. 20 cm when operating the camera ! The

camera is assigned to the Exempt Group according to IEC62471-1 and

therefore poses no risk or hazard to the human eye or skin at this dis-

tance.

Description The ARTTRACK3 camera is the successor of ARTTRACK1 which is no

longer produced. Due to its larger IR ﬂash it can be used for measurements in higher

distances (up to 6 metres). And, because of its passive cooling system (i.e. without fan),

the ARTTRACK3 is also suitable for dirty or noise sensitive environments.

By default the ARTTRACK5/C is equipped with a 4.5 mm lens. Depending on the ap-

plication and the setup the ARTTRACK3 can be equipped with other lenses (i.e. with

different focal lengths). Refer to A.1 on page 190 for a list of available focal lengths and

the respective FoV.

4 System setup

Figure 4.8: Camera ARTTRACK3

Mounting The ARTTRACK3 cameras are optimized for a predeﬁned range of measure-

ment volumes. System operation in smaller or bigger measurement volumes can lead

to reduced accuracy or other malfunctions. The measurement volume can be adjusted

within certain limits simply by changing the ﬂash intensity of the ART infrared cameras

(see chapter 4.5.6.3 on page 97).

iThe ﬂash intensities should not be too high. In general, a ﬂash inten-

sity of 3-4 might be sufﬁcient.

Major changes of the measurement volume may require different lenses and thus a new

determination of camera parameters. These changes have to be done at the ART labs.

Be aware that a tracking system is very sensitive to camera movements. Therefore, the

cameras have to be mounted in a way that reduces camera movements (especially vibra-

tions) as much as possible.

iMounting on tripods may be sufﬁcient for presentations and prelimi-

nary installations, but is not recommended as a ﬁnal solution!

If you want to mount the camera on a tripod just mount the carrier on the bottom of the

camera.

Otherwise the carrier for the ARTTRACK3 can be attached on both bottom and top side

of the camera. Attach the carrier with the T-piece pointing to the back of the camera in a

similar way to ﬁgure 4.2 on page 26. Note, the ceiling suspension is already connected to

the carrier in ﬁgure 4.2.

Chapter 4

4.1 The tracking cameras of ART

Only use screws supplied with the ceiling mount for mounting it. The

screws used for sealing the housings are not sufﬁciently long for ﬁxing

the carrier. Also, use all the parts supplied with the ceiling mount -

especially the toothed washer is quite important.

You shall never open other screws on the cameras (see chapter 1.2

on page 11). Otherwise, the camera may be damaged and liability and

warranty is void.

Feel free to contact ART in case you want to realise a more complex installation. We will

assist you in your planning.

It is recommended to install the power supply for the cameras in a way that enables the

switching of all cameras by one main switch. If this is done, the system can be easily

turned off and on without changing camera positions.

Make sure to install the system in a way that you can easily access the cameras and

its cables. Be especially careful to mount the cameras ﬁrmly so they cannot fall down.

Unsecured cameras may pose a serious hazard to health and safety.

Avoid hard shocks at all times! A new camera calibration at the ART fa-

cilities might become necessary in that case.

Figure 4.3 on page 27 shows the correct mounting for a camera to a wall with a carrier

using the example of an ARTTRACK2 camera. Make sure to not fall below minimal

distance to the wall so enough room is left for the cables and to allow readjustment of the

camera angles and maintenance.

Use strong dowels and screws for mounting the cameras to walls or ceilings (see ﬁgure

4.3 on page 27).

If in doubt, ask a skilled craftsman for assistance. Use massive and long enough angle

irons to provide the required stiffness and stability.

To avoid measurement problems, no light sources or highly reﬂecting areas should be

visible to the camera. Especially strong point light sources like e.g. halogen lamps and

direct or reﬂected sunlight may imply problems for the measurement (ﬂuorescent lamps

are ok).

Please install the cables such that

•no one can stumble over the cords,

•the cords cannot be damaged,

•the cords cannot damage the cameras due to mechanical strain,

•the line of sight of the cameras is not obstructed.

Inappropriate cabling may pose a serious hazard to health and safety.

Cable ducts or ﬁxings should be used and a strain relief should be

installed!

4 System setup

Please refer to chapter 4.2.2 on page 48 for more information.

4.1.6 TRACKPACK (discontinued)

Keep a distance of min. 20 cm when operating the camera ! The

camera is assigned to the Exempt Group according to IEC62471-1 and

therefore poses no risk or hazard to the human eye or skin at this dis-

tance.

Description The TRACKPACK is a two or four camera infrared optical tracking system

for use in medium-sized working volumes. It is the best solution for Head- and Flystick-

tracking in multi-sided projection environments (max. 3 m x 3 m x 2 m), or in front of

medium-sized projection screens (up to 4.5 m wide). The system consists of two or four

TRACKPACK cameras and a TRACKPACK Controller.

By default the TRACKPACK is equipped with a 3.5 mm lens. Depending on the applica-

tion and the setup the TRACKPACK camera can be equipped with other lenses (i.e. with

different focal lengths). Refer to A.1 on page 190 for a list of available focal lengths and

the respective FoV.

The RJ45 connection between TRACKPACK camera and controller is

used for power supply and synchronization signal. It is not a standard

Ethernet connection! That is why connecting the RJ45 connector to

any other than the equivalent port of the controller may damage the

camera or the connected partner.

Figure 4.9: Camera TRACKPACK

Chapter 4

4.1 The tracking cameras of ART

Mounting The TRACKPACK cameras are optimized for a predeﬁned range of measure-

ment volumes. System operation in smaller or bigger measurement volumes can lead

to reduced accuracy or other malfunctions. The measurement volume can be adjusted

within certain limits simply by changing the ﬂash intensity of the ART infrared cameras

(see chapter 4.5.6.3 on page 97).

iThe ﬂash intensities should not be too high. In general, a ﬂash inten-

sity of 3-4 might be sufﬁcient.

Major changes of the measurement volume may require different lenses and thus a new

determination of camera parameters. These changes have to be done at the ART labs.

Be aware that a tracking system is very sensitive to camera movements. Therefore, the

cameras have to be mounted in a way that reduces camera movements (especially vibra-

tions) as much as possible.

iMounting on tripods may be sufﬁcient for presentations and prelimi-

nary installations, but is not recommended as a ﬁnal solution!

If you want to mount the camera on a tripod just mount the carrier on the bottom of the

camera.

Otherwise the carrier for the TRACKPACK can be attached on both bottom and top side

of the camera. Attach the carrier with the T-piece pointing to the back of the camera in a

similar way to ﬁgure 4.2 on page 26. Note, the ceiling suspension is already connected to

the carrier in ﬁgure 4.2.

Only use screws supplied with the ceiling mount for mounting it. The

screws used for sealing the housings are not sufﬁciently long for ﬁxing

the carrier. Also, use all the parts supplied with the ceiling mount -

especially the toothed washer is quite important.

You shall never open other screws on the cameras (see chapter 1.2

on page 11). Otherwise, the camera may be damaged and liability and

warranty is void.

Please keep the distance between the cameras in a range of 1 to 2 metres. Depending

on the lens and the focal length it may be possible to achieve other range values. Please

contact ART for more information.

Make sure to install the system in a way that you can easily access the cameras and

its cables. Be especially careful to mount the cameras ﬁrmly so they cannot fall down.

Unsecured cameras may pose a serious hazard to health and safety.

Avoid hard shocks at all times! A new camera calibration at the ART fa-

cilities might become necessary in that case.

Figure 4.3 on page 27 shows the correct mounting for a camera to a wall with a carrier

using the example of an ARTTRACK2 camera. Make sure to not fall below minimal

distance to the wall so enough room is left for the cables and to allow readjustment of the

4 System setup

camera angles and maintenance.

Use strong dowels and screws for mounting the cameras to walls or ceilings (see ﬁgure

4.3 on page 27).

If in doubt, ask a skilled craftsman for assistance. Use massive and long enough angle

irons to provide the required stiffness and stability.

To avoid measurement problems, no light sources or highly reﬂecting areas should be

visible to the camera. Especially strong point light sources like e.g. halogen lamps and

direct or reﬂected sunlight may imply problems for the measurement (ﬂuorescent lamps

are ok).

Please install the cables such that

•no one can stumble over the cords,

•the cords cannot be damaged,

•the cords cannot damage the cameras due to mechanical strain,

•the line of sight of the cameras is not obstructed.

Inappropriate cabling may pose a serious hazard to health and safety.

Cable ducts or ﬁxings should be used and a strain relief should be

installed!

Please refer to chapter 4.2.3 on page 52 for more information.

4.1.7 TRACKPACK/C (discontinued)

Keep a distance of min. 20 cm when operating the camera ! The

camera is assigned to the Exempt Group according to IEC62471-1 and

therefore poses no risk or hazard to the human eye or skin at this dis-

tance.

Description The TRACKPACK system may also be combined with the TRACKPACK/C cam-

era in order to realize tracking in multi-sided projection environments (e.g. CAVE R

, I-

Space). In such an environment it is necessary to drill holes into the projections’ corners

as the camera cannot see through the screen. The TRACKPACK/C camera has been

designed to easily ﬁt into such holes by separating the lens from the electronics part (see

ﬁgure 4.10).

With its 3.5 mm lens a large ﬁeld of view (FoV) is covered. Refer to A.1 on page 190 for

the respective FoV.

The TRACKPACK system either consists of TRACKPACK/C cameras or it can be mixed

with standard TRACKPACK cameras - both variants are limited to a total number of four

cameras per system and come with a TRACKPACK Controller.

Chapter 4

4.1 The tracking cameras of ART

Figure 4.10: Camera TRACKPACK/C

The RJ45 connection between TRACKPACK/C camera and controller is

used for power supply and synchronization signal. It is not a standard

Ethernet connection! That is why connecting the RJ45 connector to

any other than the equivalent port of the controller may damage the

camera or the connected partner.

Mounting The TRACKPACK/C cameras are optimized for a predeﬁned range of mea-

surement volumes. System operation in smaller or bigger measurement volumes can lead

to reduced accuracy or other malfunctions. The measurement volume can be adjusted

within certain limits simply by changing the ﬂash intensity of the ART infrared cameras

(see chapter 4.5.6.3 on page 97).

iThe ﬂash intensities should not be too high. In general, a ﬂash inten-

sity of 3-4 might be sufﬁcient.

Major changes of the measurement volume may require different lenses and thus a new

determination of camera parameters. These changes have to be done at the ART labs.

Be aware that a tracking system is very sensitive to camera movements. Therefore, the

cameras have to be mounted in a way that reduces camera movements (especially vibra-

tions) as much as possible.

iMounting on tripods may be sufﬁcient for presentations and prelimi-

nary installations, but is not recommended as a ﬁnal solution!

Otherwise the carrier for the TRACKPACK/C can be attached to the camera as shown in

4 System setup

ﬁgure 4.11.

Figure 4.11: Camera TRACKPACK/C with attached carrier

Only use screws supplied with the ceiling mount for mounting it. The

screws used for sealing the housings are not sufﬁciently long for ﬁxing

the carrier. Also, use all the parts supplied with the ceiling mount -

especially the toothed washer is quite important.

You shall never open other screws on the cameras (see chapter 1.2

on page 11). Otherwise, the camera may be damaged and liability and

warranty is void.

Please keep the distance between the cameras in a range of 2 to 3 metres. Please con-

tact ART for more information.

Make sure to install the system in a way that you can easily access the cameras and

its cables. Be especially careful to mount the cameras ﬁrmly so they cannot fall down.

Unsecured cameras may pose a serious hazard to health and safety.

Avoid hard shocks at all times! A new camera calibration at the ART fa-

cilities might become necessary in that case.

Use strong dowels and screws for mounting the cameras to walls or ceilings (see ﬁgure

4.3 on page 27).

If in doubt, ask a skilled craftsman for assistance. Use massive and long enough angle

irons to provide the required stiffness and stability.

To avoid measurement problems, no light sources or highly reﬂecting areas should be

visible to the camera. Especially strong point light sources like e.g. halogen lamps and

direct or reﬂected sunlight may imply problems for the measurement (ﬂuorescent lamps

Chapter 4

4.2 The Controllers of ART

are ok).

Please install the cables such that

•no one can stumble over the cords,

•the cords cannot be damaged,

•the cords cannot damage the cameras due to mechanical strain,

•the line of sight of the cameras is not obstructed.

Inappropriate cabling may pose a serious hazard to health and safety.

Cable ducts or ﬁxings should be used and a strain relief should be

installed!

Please refer to chapter 4.2.3 on page 52 for more information.

4.2 The Controllers of ART

With the introduction of DTrack2 a new principle of controlling the tracking system is im-

plemented. The tracking system itself consists of cameras, interaction devices (optional),

targets and the ART Controller, the ARTTRACK Controller (discontinued) or TRACK-

PACK Controller (discontinued) respectively.

The software DTrack2 consists of frontend and backend software. The frontend software

is installed on a remote PC which is connected to the controller via Ethernet. A GUI for

easy handling enables the user to control the tracking system completely from the remote

PC. The beneﬁt is that the system becomes more ﬂexible, i.e. different users can con-

trol the tracking system at any one time (but not simultaneously!) from different working

places.

Furthermore, DTrack2 provides the possibility to control its functions via Ethernet (i.e.

without the DTrack2 frontend software). This is done by establishing a TCP/IP connec-

tion with the controller and exchanging short command strings (refer to chapter 4.2.8 on

page 58). Please contact ART if you are interested in using this feature.

The backend software runs on the controller - all necessary calculations (3DOF, 6DOF

data, ...) are done by the controller. The data and control commands are interchanged

via a TCP/IP connection between the controller and the DTrack2 frontend software on the

remote PC. Data output to the application or graphics workstation is done via a UDP con-

nection. The cameras (refer to chapter 4.1 on page 25) and the interaction devices (refer

to chapter 5 on page 126) have to be connected to the respective ports of the controller.

4 System setup

ART

Controller

ARTTRACK

Controller

TRACKPACK

Controller

DTrack2 1

ARTTRACK1 × × ×

ARTTRACK2 × × ×

ARTTRACK3 × × ×

ARTTRACK5 × × (from v2.10)

ARTTRACK5/C × × (from v2.11)

TRACKPACK × ×

TRACKPACK/C × × (from v2.5)

TRACKPACK/E × × (from v2.11)

Flystick1 × × × ×

Flystick2 × × × ×

Flystick3 × × × × (from v2.2)

Fingertracking 2× × × ×

Measurement Tool × × × × (from v2.2)

1an appropriate license may be necessary (refer to table 4.3)

2for Fingertracking it is recommended to use six cameras for ideal operation

Table 4.1: Compatibility of the ART cameras and interaction devices

4.2.1 Installation of the ART Controller (DTrack2 since v2.10)

The ART Controller (DTrack2 since v2.10) comes in a 19" inch housing compatible for

rack mounting, see ﬁg. 4.12 on page 44.

To turn on the controller ﬂip the power switch to I, for restart from standby mode press

the button "soft power on". The USB ports can be used for plugging in the USB radio

transceiver for the Flystick2/3 (refer to chapter 5.1 on page 128 or chapter 5.2 on page

134).

ZPlease ensure unblocked airﬂow at all times for optimal operation of

the ART Controller !

Figure 4.12: ART Controller front view

The following list introduces the ports of the ART Controller (see ﬁg. 4.13 on 45):

•ART Synccard3 (master & slave) :

Chapter 4

4.2 The Controllers of ART

–ExtIn:

Please plug in the external source (TTL or video signal) for synchronization

here. Please use the accessible port without protective cap only. In cascaded

systems please connect the external source to the master controller only. The

slave controller is then synchronized by the master.

–PoE+ ports:

All ARTTRACK1 ,ARTTRACK2 ,ARTTRACK3 ,ARTTRACK5 ,ARTTRACK5/C

and TRACKPACK/E cameras have to be plugged in here. In larger systems (>

8ARTTRACK5 and ARTTRACK5/C cameras only), please connect the exter-

nal PoE+ switch to any of these ports.

–OUT1-3 (optional):

For cascaded systems please connect OUT1 to ExtIn of a slave controller (see

chapter 4.3 on page 58). For backwards compatibility, please connect ART-

TRACK1 –ARTTRACK3 cameras here. Please refer to chapter 4.2.2 on page

48 for more detailed information.

∗OUT1:

Deﬁnes syncgroup # 1. The three different syncgroups are characterized

by their time delay related to syncgroup # 1. When using ARTTRACK1 –

ARTTRACK3 cameras at least one camera has to be connected here if you

are using active targets (e.g. Fingertracking, Flystick3). Refer to chapter

5.3 on page 137 for more information.

∗OUT2:

Deﬁnes syncgroup # 2. The default time delay related to syncgroup # 1 is

480µs.

∗OUT3:

Deﬁnes syncgroup # 3. The default time delay related to syncgroup # 1 is

960µs.

Figure 4.13: ART Controller back view

•USB port:

Please plug in the USB radio transceiver for the Flystick2/3 here (refer to chapter

5.1 on page 128 or chapter 5.2 on page 134).

4 System setup

•LAN network port:

Please connect the ART Controller to your local network using an RJ45 cable.

•Cascaded network port:

For cascaded systems please connect a slave controller to the ART Controller (mas-

ter). Please refer to chapter 4.3 on page 58 for more detailed information.

•Power inlet:

Please connect to mains (100 - 240V).

iThe power inlet is fuse-protected (2x4A, anti-surge type T) and features

a line ﬁlter for EMV protection.

IP addresses are predeﬁned in ARTTRACK and TRACKPACK/E cameras - changes by

the user are not possible!

The camera network ports are conﬁgured using:

•IP address: 172.28.0.X

•subnet mask: 255.255.0.0

In larger systems (> 8 ARTTRACK5 and ARTTRACK5/C cameras only), please use the

Netgear Prosafe GSM7212P PoE+ switch authorized by ART . It features 12 PoE+ Ports

for connection to ARTTRACK5 and ARTTRACK5/C cameras. Please use the accessible

ports without protective caps only (see ﬁg. 4.14 on page 46). To turn on the PoE+ switch,

please connect it to mains.

ZPlease allow min. 3 minutes for booting prior to starting the ART Con-

troller !

Figure 4.14: ART PoE+ switch front view

Mount the cameras at the desired position before connecting the cables.

The ARTTRACK5 ,ARTTRACK5/C and TRACKPACK/E cameras have to be connected

via twisted pair cables (min. Cat.5, max. length 100 m) to the internal ART Synccard3

of the ART Controller or to an external PoE+ switch for systems > 8 cameras (only ART-

TRACK5 and ARTTRACK5/C ). The external PoE+ switch itself has to be connected to

the Synccard3.

The ART Synccard3 is designed as a single cable solution and is therefore used both for

power and synchronization of the IR cameras.

Connection of ARTTRACK1 ,ARTTRACK2 or ARTTRACK3 cameras (backwards

compatible systems) When connecting the synchronization cables it is important to

Chapter 4

4.2 The Controllers of ART

correctly chain the cameras on the sync cable (see chapter 6.4 on page 150). There

must be one continuous signal line from the BNC connector of the synccard to the 75Ω

terminating resistor, with the cameras inserted to the line by T-junctions. It is neither al-

lowed to extend the connection between the T-piece and the camera, nor to branch the

signal line.

Usually, all cameras are connected with the sync output no. 1 ("OUT1") of the synccard

like a chain that is ﬁnished by a 75Ωterminating resistor. If the cameras have to be

grouped into different syncgroups, in order to avoid blinding, two or three BNC chains

are used at the sync outputs no. 1 and 2 or 1, 2 and 3, respectively, of the synccard3.

The settings are deﬁned by software DTrack2 . All sync signals are transferred via BNC

connections.

ARTTRACK2 and ARTTRACK3 cameras have to be connected via any

external Ethernet switch or the ART PoE+ switch and may not be con-

nected directly to the PoE+ ports of the ART Synccard3. Please refer

to chapter 4.2.2 on page 48 for more detailed information.

Furthermore, the controller uses the "LAN" ethernet plug (1000 Base-TX) for data output

to the remote PC or to any PC within the local network. Figure 4.15 on page 50 shows

two possibilities of connecting the controller to a local network. You may either use the

controller as a DHCP client within your network (ﬁgure 4.15(a)), i.e. the tracking data is

transmitted directly via your local network. Or, if due to your company security guidelines

it is not allowed to connect the controller directly to your network, you may install two

network cards in your remote PC - one is connected to the controller and the other one is

connected to your local network (ﬁgure 4.15(b)). In this case, the DTrack2 Frontend will

act as a router for the tracking data.

The controller is controlled by a remote PC via DTrack2 frontend software. When deliv-

ered, the controller is set up to support DHCP. Therefore, it will acquire an IP address

automatically given that a DHCP server is running.

Double-check if the cameras are connected properly to the controller and verify that the

cameras are running. Connect the Ethernet cable to your local network and connect the

power plug of the ART Controller to a power socket. If you want to set a speciﬁc static IP

address before booting the controller please refer to chapter 4.2.4 on page 54 for more

information.

Press the power switch on the front of the controller. If the controller is booting without

connected Ethernet cable it will use its fall-back IP address.

iThe fall-back IP address of the controller is 192.168.0.1 (subnet mask

255.255.255.0)!

You may conﬁgure another static IP address as follows:

•select Settings →Controller

•untick the checkbox DHCP client

•enter IP address and subnet mask

4 System setup

•optionally, enter gateway and nameserver

•reboot the controller for the changes to take effect

Please note that these settings are not part of your personal conﬁgura-

tion. Changes in this menu will affect all users of your controller! Your

controller may become unreachable with wrong IP settings! Refer to

chapter 4.2.4 on page 54).

Finally, start the DTrack2 frontend software on the remote PC. Please refer to chapter 4.5

on page 70 for more details.

External synchronization An ART Controller can be synchronized with an external

source. On the back of the controller there is a BNC plug ("ExtIn") which serves as input

for the external synchronization signal. The sync signal may be of type TTL or video (see

also chapter 4.5.6.3 on page 101).

Typically, external synchronization has to be used when other systems inside the tracking

system are also using infrared signals for controlling their equipment (e.g. if IR-controlled

shutter glasses are used). The goal is to reduce or eliminate interference. The ART track-

ing system follows the external synchronization signal and chooses time slots when it is

safe to emit infrared radiation without causing interference. The effect is, for example, that

active shutter glasses are not ﬂickering but offer a stable picture for the user.

The external sync input is not internally terminated.

When synchronizing with a video input, a T-piece with an external 75

Ωterminating resistor should be used if the signal line ends at the

controller.

When using a TTL-signal you should not use a terminating resistor.

However, you should use a shielded cable for the synchronization with

a TTL-signal.

4.2.2 Installation of the ARTTRACK Controller (discontinued)

The following list introduces the ports of the ARTTRACK Controller with Synccard2:

•internal Ethernet switch:

the cameras have to be plugged in here. In larger systems, please connect the

external switch to any of these ports.

•external Ethernet switch:

the Allied Telesis AT-FS708 is an eco friendly switch which is designed to minimize

power consumption (typical 3.5W) through the use of a high efﬁciency power supply

and a low power chipset. It features an overnight mode (i.e. reduction in power

during after-work hours) as well as other power saving features.

Please refer to the Allied Telesis Installation Guide before connecting the power

source.

•ART Synccard2 :

Chapter 4

4.2 The Controllers of ART

–ExtIn:

Please plug in the external source for synchronization here.

–Out1:

Deﬁnes syncgroup # 1. The three different syncgroups are characterized by

their time delay related to syncgroup # 1. At least one camera has to be con-

nected here if you are using active targets (e.g. Fingertracking, Flystick3).

Refer to chapter 5.3 on page 137 for more information.

–Out2:

Deﬁnes syncgroup # 2. The time delay related to syncgroup # 1 is 480µs.

–Out3:

Deﬁnes syncgroup # 3. The time delay related to syncgroup # 1 is 960µs.

•USB port:

Please plug in the USB radio transceiver for the Flystick2/3 here (refer to chapter

5.1 on page 128 or chapter 5.2 on page 134).

•Ethernet port:

Please connect the controller to your local network using an RJ45 cable.

Mount the cameras at the desired position before connecting the cables. The ART-

TRACK cameras have to be connected via twisted pair cables either to the internal Eth-

ernet switch of the controller or to an external Ethernet switch. The external switch itself

has to be connected to the controller.

iOlder switches sometimes do have uplink ports which are not suitable

for connecting to the camera. Only use the normal ports of the switch.

The controller is equipped with an internal switch (100 Base-TX) which serves for the

connection to the cameras (suitable for small systems, i.e. ≤4 cameras). Larger systems

(i.e. >4 cameras) have to be equipped with an external switch which must be connected

to any port (except for the uplink port) of the internal switch of the controller.

The camera network is conﬁgured using:

•IP address: 172.28.0.1

•subnet mask: 255.255.0.0

IP addresses are predeﬁned in ARTTRACK cameras - changes by the user are not pos-

sible!

The controller is equipped with a PCI card for synchronization of the IR cameras (ART Sync-

card2). When connecting the synchronization cables it is important to correctly chain the

cameras on the sync cable (see chapter 6.4 on page 150). There must be one continuous

signal line from the BNC connector of the synccard to the 75Ωterminating resistor, with

the cameras inserted to the line by T-junctions. It is neither allowed to extend the connec-

tion between the T-piece and the camera, nor to branch the signal line.

4 System setup

(a) standard connection

(b) indirect connection

Figure 4.15: Connecting the ARTTRACK Controller to a local network

Chapter 4

4.2 The Controllers of ART

Usually, all cameras are connected with the sync output no. 1 ("OUT1") of the synccard

like a chain that is ﬁnished by a 75Ωterminating resistor. If the cameras have to be

grouped into different syncgroups, in order to avoid blinding, two or three BNC chains are

used at the sync outputs no. 1 and 2 or 1, 2 and 3, respectively, of the synccard. The set-

tings of the Synccard2 are deﬁned by software DTrack2 . All sync signals are transferred

via BNC connections.

Furthermore, the controller uses the single Ethernet plug (100 Base-TX) for data output

to the remote PC or to any PC within the local network. Figure 4.15 on page 50 shows

two possibilities of connecting the controller to a local network. You may either use the

controller as a DHCP client within your network (ﬁgure 4.15(a)), i.e. the tracking data is

transmitted directly via your local network. Or, if due to your company security guidelines

it is not allowed to connect the controller directly to your network, you may install two

network cards in your remote PC - one is connected to the controller and the other one is

connected to your local network (ﬁgure 4.15(b)). In this case, the DTrack2 Frontend will

act as a router for the tracking data.

The controller is controlled by a remote PC via DTrack2 frontend software. When deliv-

ered, the controller is set up to support DHCP. Therefore, it will acquire an IP address

automatically given that a DHCP server is running.

Double-check if the cameras are connected properly to the controller. Verify that power

supplies are switched on and the cameras are running. Connect the Ethernet cable to

your local network and connect the power plug of the ARTTRACK Controller to a power

socket. If you want to set a speciﬁc static IP address before booting the controller please

refer to chapter 4.2.4 on page 54 for more information.

Press the switch next to the power plug to start the controller. If the controller is booting

without connected Ethernet cable it will use its fall-back IP address.

iThe fall-back IP address of the controller is 192.168.0.1 (subnet mask

255.255.255.0)!

You may conﬁgure another static IP address as follows:

•select Settings →Controller

•untick the checkbox DHCP client

•enter IP address and subnet mask

•optionally, enter gateway and nameserver

•reboot the controller for the changes to take effect

Please note that these settings are not part of your personal conﬁgura-

tion. Changes in this menu will affect all users of your controller! Your

controller may become unreachable with wrong IP settings! Refer to

chapter 4.2.4 on page 54).

4 System setup

Finally, start the DTrack2 frontend software on the remote PC. Please refer to chapter 4.5

on page 70 for more details.

External synchronization Any ARTTRACK system controller can be synchronized with

an external source. On the back of the controller there is a BNC plug ("ExtIn") which

serves as input for the external synchronization signal. The sync signal may be of type

TTL or video (see also chapter 4.5.6.3 on page 101).

Typically, external synchronization has to be used when other systems inside the tracking

system are also using infrared signals for controlling their equipment (e.g. if IR-controlled

shutter glasses are used). The goal is to reduce or eliminate interference. The ART track-

ing system follows the external synchronization signal and chooses time slots when it is

safe to emit infrared radiation without causing interference. The effect is, for example, that

active shutter glasses are not ﬂickering but offer a stable picture for the user.

The external sync input is not internally terminated.

When synchronizing with a video input, a T-piece with an external 75

Ωterminating resistor should be used if the signal line ends at the

controller.

When using a TTL-signal you should not use a terminating resistor.

However, you should use a shielded cable for the synchronization with

a TTL-signal.

4.2.3 Installation of the TRACKPACK Controller (discontinued)

The following list introduces the ports of the TRACKPACK Controller:

•ART SynccardTP :

The syncgroups for TRACKPACK systems can be conﬁgured in the DTrack2 fron-

tend software. Please refer to chapter 4.5.6.3 on page 97.

–ExtIn:

Please plug in the external source for synchronization here.

–Output:

The cameras have to be plugged in to the RJ45 connectors. Synchronization

and power is supplied with this connection.

•Firewire:

Please connect the TRACKPACK cameras with the controller using the delivered

Firewire cables.

•USB port:

Please plug in the USB radio transceiver for the Flystick2/3 here (refer to chapter

5.1 on page 128 or chapter 5.2 on page 134).

•Ethernet port:

Please connect the controller to your local network using an RJ45 cable.

Chapter 4

4.2 The Controllers of ART

For connecting the TRACKPACK controller to your local network, please refer to ﬁgure

4.15 on page 50. You may either use the controller as a DHCP client within your network

(ﬁgure 4.15(a)), i.e. the tracking data is transmitted directly via your local network. If, due

to your company security guidelines, it is not allowed to connect the controller directly to

your network, you may install two network cards in your remote PC - one is connected to

the controller and the other one is connected to your local network (ﬁgure 4.15(b)). In that

case, the DTrack2 Frontend will act as a router for the tracking data.

The controller is controlled by a remote PC via DTrack2 frontend software. When deliv-

ered, the controller is set up to support DHCP. Connect the Ethernet cable to your local

network and connect the power plug to a power socket. If you want to set a speciﬁc static

IP address before booting the controller please refer to chapter 4.2.4 on page 54 for more

information.

Press the switch next to the power plug to start the controller. If the controller is booting

without connected Ethernet cable it will use its standard IP address.

iThe fall-back IP address of the controller is 192.168.0.1 (subnet mask

255.255.255.0)!

You may conﬁgure another static IP address as follows:

•select Settings →Controller

•untick the checkbox DHCP client

•enter IP address and subnet mask

•optionally, enter gateway and nameserver

•reboot the controller for the changes to take effect

Please note that these settings are not part of your personal conﬁgura-

tion. Changes in this menu will affect all users of your controller! Your

controller may become unreachable with wrong IP settings! Refer to

chapter 4.2.4 on page 54).

Finally, start the DTrack2 frontend software on the remote PC. Please refer to chapter 4.5

on page 70 for more details.

External synchronization The TRACKPACK system and therefore the TRACKPACK con-

troller can be synchronized with an external source. On the back of the controller there is

a BNC plug ("ExtIn") which serves as input for the external synchronization signal. The

sync signal may be of type TTL or video (see also chapter 4.5.6.3 on pag 101).

Typically, external synchronization has to be used when other systems inside the tracking

system are also using infrared signals for controlling their equipment (e.g. if IR-controlled

shutter glasses are used). The goal is to reduce or eliminate interference. The TRACK-

PACK tracking system follows the external synchronization signal and chooses time slots

when it is safe to emit infrared radiation without causing interference. The effect is, for ex-

ample, that active shutter glasses are not ﬂickering but offer a stable picture for the user.

4 System setup

The external sync input is not internally terminated.

When synchronizing with a video input, a T-piece with an external 75Ω

terminating resistor should be used if the signal line ends at the con-

troller.

When using a TTL-signal you should not use a terminating resistor.

However, you should use a shielded cable for the synchronization with

a TTL-signal.

Be aware of the following specialty of the TrackPack system:

The TRACKPACK cameras get power supply and sync via the RJ45

cable!

Therefore, the status of the synchronization is indicated with two LEDs (orange and green)

located on the synccard of the controller. Depending on the operating condition of the

ART tracking system the LEDs are triggered respectively. Table 4.2 shows how the LEDs

are triggered according to the type of synchronization.

two LEDs (on each port of the camera network card)

↓ ↓

orange green

↓ ↓ ↓ ↓

ON OFF ON OFF

↓ ↓ ↓ ↓ ↓

ﬂashing permanently

lit

measurement

inactive

controller

switched ON

controller

switched OFF

↓ ↓

master (sync

source)

slave (sync

drain)

Status

Table 4.2: Description of the LEDs on the back of the TRACKPACK Controller

4.2.4 Setting a static IP address without the DTrack2 Frontend

(available from controller software version v2.2)

It is possible to conﬁgure the IP address of the controller without the DTrack2 frontend

software. You only need a standard USB stick (FAT32 formatted) on which you save a

setup ﬁle (format see below).

•Plug in the USB stick to the controller. It doesn’t matter if the controller is running or

not.

•If necessary start up the controller.

•Wait some time (approx. 20-30 seconds, until announced by two beeps) for the

controller to write the two ﬁles onto the USB stick.

Chapter 4

4.2 The Controllers of ART

•Unplug the USB stick.

•Now, you may view the information ﬁle or edit the setup ﬁle with any editor (instruc-

tions given in the setup ﬁle).

•In case you changed the setup ﬁle, please plug in the USB stick to the controller

again.

•Wait some time (approx. 20-30 seconds, until announced by three beeps) for the

controller to read the setup ﬁle.

•Reboot the controller for the changes to take effect.

Now, your controller is conﬁgured according to your requirements.

4.2.5 The setup ﬁle

This ﬁle is used to conﬁgure the controller without using the DTrack2 frontend software

regarding three parameters, which are:

•conﬁguring the controller to be a DHCP client,

•setting a static IP address and

•carrying out a factory reset.

Carrying out a factory reset will result in the loss of all your settings!

Following, a description of the ﬁle (e.g. ARTtrackController00117_setup.txt) format:

1# ARTtrack Controller Setup:

4# ethernet settings:

5# - uncomment just one of the lines starting with ’SETNET’

7# ethernet settings: DHCP

8# - uncomment the following line to activate DHCP

9#SETNET="dhcp"

11# ethernet settings: fix IP address and subnet mask

12# - uncomment the following line to set a fix IP address and subnet mask

13#SETNET="ip 192.168.0.1 255.255.255.0"

15# name settings: host name

16# - uncomment the following line to set the host name

4 System setup

17#SETHOSTNAME="atc"

19# name settings: domain name

20# - uncomment the following line to set the domain name

21#SETDOMAINNAME="art.site"

23# name settings: domain name server

24# - uncomment one of the following lines to set (or clear) a domain name server

25#SETNAMESERVER="192.168.0.254" # set DNS (IP or hostname)

26#SETNAMESERVER="-" # clear DNS

28# factory reset of all other settings:

29# - CAUTION: use with care, all your settings will be lost!

30# - uncomment the following line to reset all other Controller settings

31#RESETSETTINGS="yes"

Example:

If you wanted to setup a static IP you would have to remove the ’#’ sign and enter the

desired IP address, here for example: 123.123.0.1

before:

13#SETNET="ip 192.168.0.1 255.255.255.0"

after:

13 SETNET="ip 123.123.0.1 255.255.255.0"

4.2.6 The information ﬁle

This ﬁle contains the current settings of the controller. Following, a description of the ﬁle

format (e.g. ARTtrackController00150_info.txt):

ARTtrack Controller Information:

Name : atc-150

Serial Number : 00150

Ethernet (LAN) : dhcp

Ethernet IP (LAN) : 10.10.5.22 255.255.0.0 10.10.0.253

Ethernet MAC (LAN): 00:24:1D:00:C3:B3

Domain Name Server:

4.2.7 Wake On LAN

The controller is capable of Wake On LAN (WOL) if it has been forced into standby mode

before by the user (DTrack2 →Controller standby).

Chapter 4

4.2 The Controllers of ART

There are two options for waking up the controller remotely:

1. you may use DTrack2 or

2. use a separate tool (Windows: WOL program; Linux: console-based command).

Option 1 - WOL via DTrack2 Start the DTrack2 frontend software as usual. The ’Con-

nect’ button will change its name into ’Wake On LAN’ (refer to ﬁgure 4.16).

Figure 4.16: Welcome screen of DTrack2 with Wake On LAN option

Please make sure that the controller is still connected to the local net-

work! DTrack2 cannot wake up the controller if no physical connection

between remote PC and controller is established!

Press the ’Wake On LAN’ button and DTrack2 is trying to wake up the controller - this

may take up to two minutes as the controller has to boot up (see ﬁgure 4.17).

Figure 4.17: Wake On LAN progress bar

If Wake On LAN was successful DTrack2 will automatically establish the connection with

this controller and start the frontend software.

Option 2 - WOL via separate tool You will need the hostname of the controller as well

as its MAC address. To get this information, please press Settings →Controller and re-

member the ’hostname’ and its MAC address (’ethernet-MAC LAN’).

4 System setup

If you are a Windows user you need a separate WOL program to use this feature. Please

refer to the manual of the WOL program you are using to ﬁnd out how to conﬁgure the

WOL function.

When using Linux you only need to switch to the console and type in the following com-

mand and your controller restarts:

for Linux openSUSE:

$ wol <MAC address of your ATC>

e.g.: $ wol 00:1D:92:3A:58:5F

for Ubuntu:

$ wakeonlan <MAC address of your ATC>

e.g.: $ wakeonlan 00:1D:92:3A:58:5F

4.2.8 Remote command strings

The following commands may be used in combination with the DTrack2 SDK to control

the tracking system remotely (e.g. with your media control) and without the DTrack2 fron-

tend. The DTrack2 SDK is available from ART upon request.

Command string (always preceded by "dtrack2") Description

tracking start Start the measurement

tracking stop Stop the measurement

set conﬁg active_conﬁg <name> Change the conﬁguration to <name>

set output net <channel id> udp <host> <port> Conﬁgure where the data has to be sent to

example: dtrack2 set output net ch02 udp 231.231.0.1 5003

set output net <channel id> multicast <host> <port> Conﬁgure where the data has to be sent to

example: dtrack2 set output net ch02 multicast 231.231.0.1 5003

set output active <channel id> <output type> <yes/no> Activate or deactivate the data output and specify

the data to be transmitted

example: dtrack2 set output active ch02 all yes

system shutdown Force the controller to go into standby

system reboot Shut down the controller and reboot automati-

cally afterwards

4.3 Setting up cascaded systems

Cascading means that two or more stand-alone tracking systems are combined to one

large system in order to have only one consolidated data output. It is possible to cas-

cade TRACKPACK/E systems with or without ARTTRACK5 and ARTTRACK5/C and to

build cascades out of ARTTRACK (discontinued) with TRACKPACK systems (discon-

tinued). Therefore, the system is subdivided into one master and up to eight slaves.

However, the total number of cameras in the cascaded system cannot exceed 16 for

TRACKPACK/E only systems and 50 for combined ARTTRACK5 &ARTTRACK5/C and

Chapter 4

4.3 Setting up cascaded systems

TRACKPACK/E systems respectively.

The task of the master is to gather all single data outputs from all slaves and to merge

them into one single data output. The DTrack2 frontend connects to the master only and

allows to conﬁgure (e.g. cameras, output, tracking, etc.) the entire tracking system as

usual.

The master has to be an ARTTRACK Controller with "full-featured" li-

cense (< DTrack2 2.10) and a Synccard2.

Starting with DTrack2 version v2.10 a new license model has been es-

tablished. The master controller needs to have a dedicated "cascaded

systems" license as well as a sufﬁcient license for ALL cameras in the

cascade, e.g. 4 ARTTRACK5 + 4 TRACKPACK/E cameras = license for

8 cameras.

Depending on your setup there are different options how to connect the single tracking

systems within a cascade.

Option 1 - master: all ART and ARTTRACK Controllers, slave(s): ART Controllers

with TRACKPACK/E or TRACKPACK controllers (discontinued) Connect the data

output of the slave controller(s) and the one of the master to the same local area network

LAN (e.g. application network, see option 1 in ﬁg. 4.18 on page 60 and ﬁg. 4.19 on page

61).

Option 2 - master: ART Controllers (DTrack2 => v2.11), slave(s): ART Controllers

with TRACKPACK/E or TRACKPACK controllers (discontinued) Connect the data

output of the slave controller(s) to the cascaded network port of the master (see option 2

in ﬁg. 4.18 on page 60). Please use a switch for two or more TRACKPACK slaves.

Option 3 - master: ARTTRACK controllers (discontinued), slave(s): TRACKPACK con-

trollers (discontinued) Connect the data output of the slave controller(s) to the camera

network of the master (see option 3 in ﬁg. 4.19 on page 61).

4 System setup

Figure 4.18: Principle of cascading using the LAN (option 1) or the cascaded network port

(option 2 - master ART Controller & DTrack2 => v2.11)

Additionally to the aforementioned ﬁgures, please proceed according to the following de-

scription:

1. mount the cameras as usual at the deﬁned positions

2. connect all cameras to their corresponding controller as usual

3. establish a BNC connection between the master’s OUT1 connector and the EXT.In

of the slave(s) for synchronisation of cascade

The USB Radio Transceiver2 for Flystick2 and Flystick3 has to be con-

nected to the master controller.

Double-check if the cameras are connected properly to every controller. If applicable ver-

ify that all power supplies are switched on and the cameras are running (indicated by two

LEDs at the front side of the cameras).

Chapter 4

4.3 Setting up cascaded systems

Figure 4.19: Principle of cascading using the LAN (option 1) or the internal camera net-

work (option 3 - master ARTTRACK controller (discontinued))

The master controller is controlled by a remote PC via DTrack2 frontend software. When

delivered, controllers are set up to support DHCP. When building cascades via LAN (op-

tion 1, see 4.18 on page 60) they will acquire an IP address automatically given that a

DHCP server is running. If you want to set a speciﬁc static IP address before booting the

controllers please refer to chapter 4.2.4 on page 54 for more information.

If the cascade is connected via the cascaded network port of the

ART Controller (option 2, see 4.18 on page 60), all slave controllers

must be set to a speciﬁc static IP address in the subnet 172.29.xxx.xxx

with subnet mask 255.255.0.0 !

In case of using the internal camera network (option 3, see 4.19 on page 61), all slave

controllers will acquire their IP addresses automatically.

Press the power switches (next to the power plug or on the front) to start the master and

the slave controller(s). Make sure the controllers are booted up with all necessary ether-

4 System setup

net connections, otherwise the fall-back IP address is applied.

iThe fall-back IP address of the controller is 192.168.0.1 (subnet mask

255.255.255.0)!

Finally, start the DTrack2 frontend software on the remote PC and establish a connection

to the master.

iWe recommend creating a new conﬁguration for all cascaded systems:

DTrack2 →Conﬁgurations →’New’

Now, go to Settings →Cascaded System and the main setup dialogue for the cascade

will open up. Basically, you have the possibility to select single tracking systems to join in

the cascade. When using Option 1 (Connection via LAN), you can tick the checkbox ’scan

LAN’ and DTrack2 will search automatically whether controllers are available to become

slaves. They will be listed in the table on the right-hand side of the dialogue (refer to ﬁgure

4.20).

Figure 4.20: Cascaded System Settings

Click on the desired Controller and press ’Select’ in order to add it to the cascade. Repeat

these steps if you want to add more single controllers to the cascade.

Make sure that the checkbox ’wake on LAN’ is ticked. This option will enable synchronized

starting and shutting down of the master and all slave controllers. Starting of the cascade

will take 3-4 minutes as the master has to boot up ﬁrst and then wake up the slave(s). If

the option ’wake on LAN’ is not ticked, the slave(s) WILL NOT be started or shut down

automatically.

The changes will be accepted by the system if you press ’OK ’. Settings (e.g. ﬂash in-

tensity, sync groups) of all cameras inside the cascade can now be edited through the

Settings →Cameras dialogue. The next time you start the measurement all cameras

Chapter 4

4.4 Setting up the Hybrid Motion Capture System

inside the cascade can be viewed through the Monitor 2DOF display.

Before continuing, please double-check whether a BNC connection

for synchronization has been established between master (OUT1) and

slave(s) (EXT.In).

Now, you can proceed with calibrating the room as usual. Please refer to chapter 4.5.2

on page 77 where room calibration is explained.

4.4 Setting up the Hybrid Motion Capture System

With the introduction of v2.9.0 DTrack2 supports inertial sensors which are distributed

with our Hybrid Motion Capture suit. The main advantage of hybrid targets is that inertial

sensors still deliver information through the rotation of the target, even when the optical

target may not be tracked any longer due to viewing limitations or occlusions. On the

other hand, drift correction of the inertial sensors is achieved by fusing their output with

position measurements calculated from the optical tracking system. Inertial sensors are

communicating with the DTrack2 system via a 2.4 GHz ISM radio connection.

Connecting the wireless transceivers The wireless antenna comes pre-assembled

with two transceivers (’Dongles’) for communication with the inertial sensors. First con-

nect the USB plugs of these dongles to any free USB port of the controller using the

supplied extension cables. The dongles are activated after rebooting the controller or

calling DTrack2 →Search hardware.

Be sure just to use active (USB 2.0) extension cables (like the supplied

’ATEN UE250’) to connect transceivers (’Dongles’) to an ART Con-

troller. Otherwise proper function of the transceivers cannot be guar-

anteed.

Now within DTrack2 go to Settings →Inertial Sensors and check that all attached dongles

have been found with correct device ID, model, name, ﬁrmware version and channel (see

ﬁgure 4.21 on page 64). Please also check the frequency the sensors are operating at

(default: 100 Hz).

At this point only dongles and no wireless sensors should be listed. Otherwise continue

reading in chapter 4.4 on page 66.

The default channels for all dongles and sensors are 35 and 55 (out of

80). In case these frequencies are already occupied by other devices

in range (e.g. WLAN), connection problems may occur. ART recom-

mends to scan for available channels and to select free channels ac-

cordingly. Keep a minimum distance of 10 channels between dongles

or from otherwise unavailable channels for optimum connectivity.

Next scan the available radio channels by pressing Scan available channels. After com-

pletion the drop-down menu in the column Channel will show a list of all available chan-

nels for each dongle. The currently used channels are marked in bold digits, while all not

4 System setup

Figure 4.21: Inertial Sensor Settings

recommended channels are greyed out. If the current channel of a dongle is not suitable,

DTrack2 recommends another one (marked green).

Please select an appropriate channel for each dongle. The selected dongle will change

its channel accordingly, like for all assigned sensors. Do not set both dongles to the same

channel or on occupied frequencies from other devices in range.

Adding the inertial sensors to the conﬁguration in DTrack2 This needs to be done

initially - in case the sensors are already connected please skip this step.

Please ensure that all sensors have been charged or alternatively attach the sensors to

the supplied charging hub prior to the following steps.

In the menu Settings →Inertial Sensors, press Add sensor to identify and connect all

inertial sensors in range.

In the appearing dialogue (see ﬁgure 4.22 on 65) you should ﬁnd the Scan mode being

’default’. In this mode DTrack2 will search for the sensors on default channels 35 and

55, even if the dongles / sensors have been set to different channels manually. In this

case, please change the scan mode to ’single’ and select the corresponding channel in

the adjacent selection box. If you don’t know the current radio channel of your sensors,

choose ’all’ (takes some time). With ’USB’ you can identify sensors that are connected to

the ART Controller via a USB charging cable.

Press Scan and the system will identify all sensors in range. Expect 15 inertial sensors

for a complete ART Hybrid Motion Capture suit. Tick the checkboxes of all sensors to be

added to the conﬁguration in the column Accept or add all sensors by ticking ’accept all’.

Then press Apply and exit this dialogue.

Chapter 4

4.4 Setting up the Hybrid Motion Capture System

Figure 4.22: Add Sensors

ART delivers a pre-calibrated hybrid motion capture suit, i.e. both the

optical target geometry as well as the HBC result are stored directly

on the sensor. Unless the hybrid target is disassembled or becomes

damaged, it is sufﬁcient to identify and add all sensors using the menu

Settings →Inertial Sensors →Add Sensors. There is no need to cali-

brate the targets manually.

The dialogue Inertial Sensor Settings (see ﬁgure 4.21 on 64) now shows all available

dongles and sensors with the following properties:

•Device ID + wireless icon

•Model (e.g. Colibri Wireless)

•Name (targets from Hybrid Motion Capture suit or user-deﬁned)

•Firmware Version

•Currently used channel (default: 35 / 55); with this menu you can also change the

radio channel of a single sensor

•Wake-up mode (radio, tapping, USB/button)

•Battery level

•Temperature (only during measurement)

Take care that all inertial sensors use a radio channel of one of the

dongles; otherwise this sensor won’t be used during measurement.

Also take care that (approximately) the same number of sensors are

assigned to each dongle.

4 System setup

The temperature values between single inertial sensors may vary. The

operating temperature is reached as soon as there are no more tem-

perature changes inside the sensors indicated by a green status bar. It

is not dependent on the absolute temperature value.

For warming up the sensors to operating temperature press the button Warmup start.

All inertial sensors are turned to stand-by mode after a pre-deﬁned idle time, which cor-

responds to the selected wake-up mode.

via: radio (idle time: 1 min.), i.e the sensors are switched on as soon as they are ad-

dressed by the controller.

via: tapping (idle time: 3 min., older sensors only), i.e. the sensors are switched on by

tapping on the sensors with your ﬁngertip or tapping the sensors on a hard surface

(e.g. table).

via: USB/button (idle time: 10 min.), i.e. the sensors are switched on by pressing the

button on the sensor for 3-4 seconds or by connecting them to the supplied charging

hub.

ZFor optimal battery life, ART recommends to switch all sensors to

wake-up mode "USB/button" when not in use for a longer period of

time.

Calibration of Hybrid Bodies As requirement for the following steps it is necessary to

warm-up the sensors to operating temperatures and to maintain a constant temperature

during the calibration. Otherwise the measured data and thus the calibration will have

poor quality. Additionally please double-check that all sensors have been charged to at

least 30 % before you continue.

You can simply use the button Warmup start in the dialogue Inertial Sensor Settings (see

ﬁgure 4.21 on 64) or in DTrack2 frontend (top right) and leave the process running for

about 5-10 minutes. The progress bar will stop at 100% (progress bar turns green) even

though the warming up of the sensors continues. This shall guarantee that the sensors

work continuously until the calibration and the actual measurement take place. Otherwise

they would cool down again.

Administration of the bodies Within DTrack2 go to Settings →Body Administration (see

ﬁgure 4.46 on page 105). All ART pre-calibrated targets have their corresponding optical

target geometries stored inside the inertial sensor. Thus when adding the recognized

inertial sensors, all corresponding target geometries are also added to the tab ’standard

bodies’ in the Body Administration (F8). Unknown or custom hybrid targets, however, will

show up as ’not calibrated’ in the column Calibration. At this point the desired optical

target and the corresponding inertial sensor have to be matched according to their body

ID and device ID.

For new hybrid targets, a three-step calibration procedure has to be performed:

Chapter 4

4.4 Setting up the Hybrid Motion Capture System

1. A standard optical body calibration needs to be carried out. Just press Calibration

and move around the target in front of the cameras. Please refer to 4.5.3 on 84.

2. A hand-eye calibration has to be performed to combine an inertial sensor with its

corresponding optical target. During this Hybrid Body Calibration process (HBC)

the relative rotation of the two sensors is determined.

3. Drift correction for the inertial sensors needs to be measured and applied. Optical

tracking data of the corresponding target allows for correction of residual drift of the

inertial sensor.

ZPlease perform all inertial sensor calibrations with warmed-up sensors

in a constant temperature environment for optimum tracking perfor-

mance.

Hybrid Body Calibration Select the sensor to be calibrated and press Hybrid Body Cali-

bration (see ﬁgure 4.23 on page 67). During this calibration the target has to be moved

with moderate speed in any spatial direction of the inertial sensor (please refer to the an-

imation in the HBC dialogue). Select the desired target from the drop-down menu ’Body

ID’ and check the ’sensor ID’ of the inertial sensor for correspondence with the selected

optical target. Then press Calibrate. The appearing dialogue will show the status of the

calibration via a progress bar.

Figure 4.23: Hybrid Body Calibration

As a result you will receive a value for the residual of the calibration. This residual is a

representation of how well the rotational data from the inertial sensor matches the optical

tracking data. Thus it is a measure of the accuracy of the HBC. Values ranging from 1◦to

2◦are ideal. Anything less than 3◦is still acceptable. Please refer to ﬁgure 4.24 on page

In case the values are acceptable you can assign the calibration and return to the Body

Administration. Now, the sensor should show ’full’ in the column Calibration. Repeat this

procedure for each sensor.

4 System setup

Figure 4.24: Hybrid Body Calibration Result

ZPlease perform all inertial sensor calibrations with warmed-up sensors

in a constant temperature environment for optimum tracking perfor-

mance indicated by a green temperature bar.

Inertial Sensor Calibration After successful calibration of all hybrid bodies, a drift correc-

tion for all inertial sensors should be measured and applied. To this end, please select

Calibration →Inertial Sensor Calibration (see ﬁgure 4.25 on page 69). Put all sensors in

the tracking volume (pre-condition: a successful Hybrid Body Calibration for each inertial

sensor) or put them anywhere on a level surface. Do not move or touch them during

the following calibration. Tick the checkboxes in the column Calibrate of all sensors to

be calibrated and press Calibrate. Values around 0.1◦are ideal and still acceptable up to

0.2 ◦, values indicate possible movement during the calibration. When the calibration is

done, you can apply the drift correction either to single sensors by ticking the appropriate

checkboxes in the column Accept or by ticking ’accept all’ for all sensors in range. Press

Apply and exit the dialogue.

iAfter the Inertial Sensor Calibration has been performed and applied

its result is stored directly on the sensor for future use.

Chapter 4

4.4 Setting up the Hybrid Motion Capture System

Figure 4.25: Inertial Sensor Calibration

4 System setup

4.5 DTrack2 frontend software

The software DTrack2 is intended to run on a remote PC (Windows or Linux). The Con-

troller can be controlled remotely via Ethernet. The software DTrack2 itself is delivered

via USB pen-drive or can be downloaded in the latest version from our Download Center

at http://www.ar-tracking.com/support/.

4.5.1 Getting started

Please refer to chapter A.5 on page 197 for more information on supported operating

systems.

4.5.1.1 Installation guide (Windows)

Run the installation executable "DTrack2_v2.x.x_win32_install.exe" and the installation

wizard of DTrack2 starts.

Click Next to continue and to start the installation

process for ART DTrack2 software. Administra-

tor rights are not necessary.

Now, please choose the destination folder in

which you want to install DTrack2 .

Chapter 4

4.5 DTrack2 frontend software

Please read the license terms carefully and

press I Agree if you agree indeed. A new win-

dow shows the installation progress.

The installation of the DTrack2 software is com-

plete now. DTrack2 has been installed on your

computer. Click Next.

Press Finish to complete the DTrack2 setup wiz-

ard. Now, you can use DTrack2 .

4.5.1.2 Installation guide (Linux)

The software (32-bit and 64-bit package available) is packed in an archive.

(DTrack2_v2.x.x_linux32.tar.gz) You do not need to have administrator rights to extract

all ﬁles to a user-deﬁned folder. In a shell, change to the user-deﬁned folder and type in

the command tar xvf DTrack2_v2.x.x_linux32.tar.gz in order to extract the ﬁles. For

ease of use, you may create a shortcut on the desktop.

DTrack2 can be started with the command ./DTrack2.

4 System setup

4.5.1.3 Software update

The latest DTrack2 software is always available from our Download Center at http://www.ar-

tracking.com/support/. For the installation of the update, please proceed as mentioned

before in chapters 4.5.1.1 and 4.5.1.2.

After installing DTrack2 on the host PC the Controller can be updated after establishing

a connection to the Controller with the new Frontend.

4.5.1.4 Start DTrack2 frontend software

When you start DTrack2 on the remote PC you will see the following start window (see

ﬁgure 4.26).

Figure 4.26: Welcome screen of DTrack2

4.5.1.5 Connecting to the controller

The ﬁrst time you start DTrack2 , no default controller will be found and another window

will be opened automatically (see ﬁgure 4.27). The radio button at position Speciﬁc Con-

troller will be ticked.

If you know the name (typically like "atc-00069") or IP address of your controller you may

enter it in line hostname or IP address and press Connect.

Otherwise, you can select Scan, if you don’t know the hostname or the IP address of your

controller. You will see a list of the available controllers in your network.

In column Name every controller in your network will be listed. If no controller or not the

desired controller is listed there please press Update list. Now, the list should contain

your desired controller. If not, please refer to chapter 6 on page 147.

You can identify the correct controller by comparing the serial number on the label on

the back of the controller with the serial number listed in this window (column Serial).

Controllers set in grey are used by other PCs in the network (→IP address listed at the

bottom of the welcome screen). It is only possible to connect to controllers set in black.

Chapter 4

4.5 DTrack2 frontend software

(a) speciﬁc controller (b) scan the network

Figure 4.27: Controller Selection

Select the entry which ﬁts to your desired controller and press Connect.

The next time you start DTrack2 your controller is still known by the software and DTrack2 au-

tomatically searches for it. The welcome screen shows the name of your controller. If this

is the one you want to connect to, just press Connect.

The graphical user interface The graphical user interface of DTrack2 offers different

views which can be switched on and off by the user:

1. Monitor 2DOF Graphical display of markers seen/tracked by the cameras.

Colour code signiﬁes the circularity or the size of the mark-

ers, respectively.

2. Event Display Displays DTrack2 events (e.g. "no valid room calibration")

3. Data Display Displays measurement results (6DOF and/or 3DOF)

4. Fingertracking Shows the measurement results of the hands

5. Flystick Shows the measurement results (6DOF) and the operation

of the buttons and the joystick

6. Measurement Tool Shows the measurement results of the Measurement

Tool and, if assigned, the reference body

By default the ﬁrst three are shown (see ﬁgure 4.28).

In the status bar, a button for starting and stopping of the measurement is integrated.

Additionally, you may retrieve information regarding the cameras connected, the synchro-

nization frequency, the number of bodies tracked and the number of single markers seen.

The synchronization frequency ﬁeld is changing its colour to yellow, orange and red in

case the effective frequency is decreasing (see ﬁgure 4.29):

•grey: max. 5 frames per minute lost (i.e. 3600 frames per minute are transmitted)

•yellow: 5 - 10 frames per minute lost

•orange: 10 - 15 frames per minute lost

4 System setup

•red: > 15 frames per minute lost

Figure 4.28: Graphical user interface of DTrack2

(a) yellow: 5 - 10 frames per

minute lost

(b) orange: 10 - 15 frames per

minute lost

lost

Figure 4.29: Visualization of the synchronization frequency decrease

4.5.1.6 Adjustment of the cameras

So far, the cameras have been mounted and connected to the controller. The next step

is to adjust the orientation of each camera such that the measurement volume can be

tracked completely. It is especially important that blinding of one camera by another one

is excluded. Therefore, DTrack2 provides the Monitor 2DOF display that essentially is a

graphical display of the ﬁeld of view of the IR cameras and of the markers that are seen

by the cameras (presented two-dimensional).

Monitor 2DOF display The Monitor 2DOF view shows a black window for each IR cam-

era (equivalent to the ﬁeld of view) with a schematic display of positions and sizes of all

recognized markers. A simple colour code signiﬁes the size and the circularity of the

Chapter 4

4.5 DTrack2 frontend software

markers (green = very good quality, yellow = good quality, red = bad quality). As a rule

of thumb, for measurement applications with high accuracy requirements the markers

should be displayed in green; for VR applications yellow markers are always ok. The

Monitor 2DOF display is particularly useful for the ﬁnal adjustment (especially orientation

adjustments) of the IR cameras.

Additionally, the intensity of the brightest pixel in the ﬁeld of view is shown using a bar dis-

play for ARTTRACK2 ,ARTTRACK3 ,ARTTRACK5 and TRACKPACK cameras (refer

to ﬁgure 4.28). When using an ARTTRACK1 you’ll ﬁnd the bar display integrated in the

camera on the front side.

A click with the right mouse button into one of the windows opens a menu (see ﬁgure

4.30) with settings for the respective camera.

Figure 4.30: Monitor 2DOF view menu (e.g. camera 1)

By clicking and holding the left mouse button on one of the camera displays, its position

can be moved within Monitor 2DOF view.

A more detailed description of the features of the Monitor 2DOF view can be found in

chapter 4.5.6.5 on page 120.

Adjustment of the cameras During this adjustment the user should take care to avoid

mutual blinding of the cameras. If the IR ﬂash of one camera is inside the ﬁeld of view

of another camera, this situation can, but has not necessarily to be visible in the Monitor

2DOF view. Blinding is often indicated by the observation that the LED bar shows high

intensity, but no markers are inside the measurement volume and the camera does also

not recognize any markers (no marker displayed in Monitor 2DOF view). If this is the

case, it will severely affect tracking in the involved image areas. If these situations cannot

be avoided by proper adjustment of the cameras (i.e. position and orientation), they can

be arranged in different ﬂash groups, thus separating the IR ﬂash of one camera from the

image recording of the other camera on a time scale.

4 System setup

On the one hand, camera mounting has to ensure that tracking is possible over the entire

measurement volume. On the other hand, attention has to be paid to the fact that at least

two cameras have to see the calibration angle (for room calibration) completely. Moreover,

the ﬁelds of view of the single cameras have to overlap sufﬁciently, in order to enable the

photogrammetric orientation of all cameras in a common coordinate system; especially if

not all IR cameras are able to see the calibration angle.

License overview Up to DTrack2 v2.10 different license models were available for ART-

TRACK and TRACKPACK systems:

•ARTTRACK systems →extended and full-featured licenses

•TRACKPACK systems →basic, extended and full-featured licenses

Starting with DTrack2 version v2.10 a new license model has been established.

You may use 2, 4, 8, 16 or up to 50 cameras in any combination with 4, 10, 30 or up to 50

targets depending on the license purchased.

Please refer to table 4.3 for a detailed overview.

Feature denotation Values Possible license status

Cascaded supported / not supported

Fingertracking supported / not supported

Measurement Tool supported / not supported

DTrack2 cameras not supported

DTrack2 max. Ccameras 1C= 2, 4, 8, 16 supported

DTrack2 all cameras supported

DTrack2 max. Bbodies B= 4, 10, 30 supported

DTrack2 all bodies supported

1Max. 4 TRACKPACK (discontinued) or 8 TRACKPACK/E cameras without cascaded

system.

Table 4.3: Licenses overview

iThe maximum number of bodies that may be used in the ARTTRACK or

TRACKPACK system includes the calibrated interaction devices (Fin-

gertracking, Flystick, Measurement Tool )!

4.5.1.7 Localizing and removing of disturbing reﬂections

Reﬂections may be detected when starting the Monitor 2DOF view in DTrack2 . They are

illustrated the same way as single markers, i.e. with small coloured crosses. But, there

may also be reﬂections that are not illustrated in the Monitor 2DOF view when mutual

blinding of cameras occurs. Then, you can only tell from the bar display which is indicat-

ing (high) radiation intensities.

This is a known behaviour which, in case of ARTTRACK2 , can be solved easily with

an update of the cameras’s ﬁrmware. Please contact ART in case you experience alike

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4.5 DTrack2 frontend software

problems.

Sources of disturbing reﬂections may be diverse. Typically, however, the reﬂections are

produced from one (or more) of the following:

•strong infrared radiation sources (e.g. sunlight or sunrays, halogen lamps, ...),

•mutual blinding of infrared cameras,

•active or passive targets, that are still in tracking range of the cameras,

•any kind of reﬂecting material on clothes or shoes,

•blank metal surfaces, especially curved surfaces and surfaces with 90◦angles,

•some types of packaging foils.

For removing disturbing reﬂections there are different approaches:

•reduce the ﬂash intensity of all cameras to "0":

remaining reﬂections are originating from infrared radiation sources (e.g. sunlight,

halogen lamps, ...). Try to localize and remove them.

•reduce the ﬂash intensity for one camera after the other to "0":

remaining reﬂections are caused by mutual blinding of the cameras. Turn the cam-

era until the bar displays’ segments of the Monitor 2d display do not indicate radia-

tion any more. You may also introduce new syncgroups in order to eliminate mutual

blinding.

•try to localize the reﬂection by moving a target towards the origin of the reﬂection

(use the Monitor 2DOF display) and proceed as mentioned above.

If reﬂections cannot be eliminated you may use the reﬂex suppression tools of DTrack2 (please

refer to 4.5.6.3 on page 98):

1. static reﬂex scan:

reﬂexes will be suppressed automatically by DTrack2 upon detection

2. suppress static reﬂexes manually :

areas to be suppressed may be deﬁned manually

4.5.2 Room calibration

Before you can start tracking, a room calibration has to be carried out. During that cali-

bration, the system identiﬁes the position of the cameras inside the measurement volume

and determines the three-dimensional coordinate system. Carrying out a room calibration

always is the ﬁrst step. Without it, body calibration and tracking will not be possible.

iThe Show details option offers information about the date of the last

room calibration.

Room calibration has to be carried out

4 System setup

•after the ﬁrst system setup,

•after any changes of IR camera positions (→Room re-calibration),

•after any changes to the number of cameras,

•before a body calibration (when system has been setup initially).

In principle, it is recommended to always perform a room calibration after a certain oper-

ating time of the system, especially if the system setup does not exclude camera move-

ments over time (these camera movements may also be thermal drifts!).

If a camera with 4.5mm lenses (standard for ARTTRACK3 ) is rotated

by one tenth of a degree it will cause aberrations of the optical rays

that are as high as 5 millimetres in 3 metres distance from the camera.

That means for the DTrack2 software (standard settings) that the ob-

servations of this camera are excluded from the calculation of target

positions because these observations would generate unacceptable

errors in the results of measurement. I.e., a camera that is rotated by

one tenth of a degree does not contribute to tracking any more!

For that reason, a room calibration should be carried out whenever any uncertainty re-

garding the mechanical stability or the thermal behaviour of the setup occurs.

For room calibration, the calibration angle of the "room calibration set" is inserted into the

ﬁeld of view of the IR cameras. The position of the calibration angle deﬁnes the room

coordinates. At least two IR cameras have to see all markers of the calibration angle.

Therefore, DTrack2 ’s Monitor 2DOF display is started in the background when selecting

Calibration →Room. Here you can verify that all markers of the angle are seen by the

cameras.

iThe longer arm of the angle deﬁnes the X axis (refer to ﬁgure 4.32); the

shorter one the Y axis. The center of marker #1 deﬁnes the origin of

the room coordinate system (at a height of 43mm).

The pre-calibrated stick carrying two markers is called the "wand". Its function is to create

a virtual "point cloud" in the measurement volume that is used for calculating the relative

positions of the IR cameras with high accuracy. Furthermore, the wand is scaling the

system. That’s why damages of the wand (loose markers, bent poles, etc.) lead to mis-

calculations of the measurement volume.

To choose the marker distances of the calibration angle three predeﬁned settings are pos-

sible, representing the common ART Room Calibration Sets.

Marker distances of the calibration angle can also be set manually using the setting ex-

pert. The numbering of the markers is as seen in ﬁgure 4.32.

The wand length has to be set manually in this dialogue - it is written on the label of the

wand.

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4.5 DTrack2 frontend software

Figure 4.31: Room calibration settings (e.g. RCS 410)

wand length marker height H TRACKPACK ARTTRACK2 ARTTRACK3 ARTTRACK5

diameter (see Fig. 4.32)

RCS TP 410.0mm 20mm 58mm ×

RCS 410 410.0mm 20mm 43mm ×××

RCS 710 710.0mm 20mm 43mm ×××

RCS 720 720.0mm 30mm 48mm ×××

Table 4.4: Overview of the ART Room Calibration Sets (RCS)

Figure 4.32: Marker distances (including numbering) on the angle and deﬁnition of room

coordinate system

Incorrect input data for this dialogue will lead to a poor room calibra-

tion, to wrong system scaling, or to an abortion of the whole room

calibration process.

With the select list at the bottom you may deﬁne how the coordinate system of the room

is created relative to the calibration angle (refer to table 4.5).

After pressing Calibrate, the room calibration is started with ﬁve seconds delay.

4 System setup

Standard Powerwall

In the Standard setting the

angle deﬁnes the X/Y plane (X

at the long, Y at the short

beam) and Z upward.

With the Powerwall setting the

X/Y plane is in the screen and

the Z axis pointing out of the

screen. This is the standard

screen coordinate system of

many VR systems (e.g.

OpenGL, TrackD, etc.).

Table 4.5: Options for coordinate system deﬁnition

A window showing the progress of the room calibration appears (see ﬁgure 4.33(a)). The

progress is shown for each camera which is especially helpful for big systems. As soon

as the display for a camera changes its colour to green (see 4.33(b)) enough data for

calculation of the camera position has been collected for this camera.

ARTTRACK5 only: This progress is also displayed individually on each cameras corre-

sponding 2-digit LED matrix. After collection of sufﬁcient data the LED matrix changes

back to its deﬁned setting. Please refer to chapter 4.5.6.3 on page 97 for detailed infor-

mation.

(a) (b)

Figure 4.33: Room calibration progress

If necessary, you may adjust the ’duration’ of the room calibration (→Show details) in

a range of 10s - 100s. Resetting the value to default is achieved by pressing the Set to

default button (default = 30s).

Changing the duration of the room calibration, especially towards

shorter durations, may lead to bad room calibration results! Please

make sure that you are always able to cover two thirds of the tracking

volume within the set time.

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4.5 DTrack2 frontend software

Move the wand gently within the measurement volume, in order to generate a virtual point

cloud. This point cloud should ﬁll at least about two thirds of the measurement volume. It

is used for calculation of IR cameras positions, so moving the wand in only a very small

volume will result in reduced accuracy of calibration. Here, a compromise has to be found

between (1) too wide movements that often cause the failing of room calibration, and (2)

sparse movements that lead to a valid, but inaccurate room calibration. Avoid rapid and

hectic movement (see ﬁgure 4.34).

Figure 4.34: Room calibration process

During calibration, the two markers of the wand should be visible to all IR cameras as

good as possible. If, in a system setup, no sufﬁcient part of the measurement volume is

seen by all IR cameras simultaneously, the point cloud created by the wand movement

has to connect all cameras in a way that ensures the arrangement of all cameras in a

common room coordinate system. More concrete, cameras that see the calibration an-

gle are oriented ﬁrst. Then, every additional camera has to be connected by a sufﬁcient

volume with at least two already oriented cameras. In this way, the calibration is stepping

forward from camera to camera. (e.g.: cameras 1 and 2 are seeing the angle - camera 3

overviews a certain volume together with cameras 1 and 2 - camera 4, ﬁnally overviews

a volume together with cameras 1 and 3).

Calibrating cameras which do not observe the angle directly is called "chain calibration".

Chain calibrated cameras propagate inaccuracies from the previously calibrated cameras.

It is recommended to place the calibration angle in a point where as many cameras as

possible can see the angle.

After a successful room calibration, the DTrack2 info window with the calibration results is

displayed. This window shows the mean residuals for the single cameras (here: ’Residual’

= mean residual of rays during marker detection), as well as the mean deviation (’wand

residual’) and the maximum deviation (’wand range’) of wand length during the calibration

process. These values depend on the system geometry and can give information about

the quality of calibration only to an experienced user. The value ’Used Frames’ represents

4 System setup

the percentage of valid (i.e., used for room calibration) data for each camera. It should

be as high as possible for all cameras. Values under 50% indicate poor room calibration

quality. The number of valid frames should be greater than 70% for each camera. The

room calibration is conﬁrmed (i.e., the data are stored) by pressing the button OK .

ZPlease note that percentages of more than 70% may not be reached in

large and complicated measurement volumes.

Figure 4.35: Room calibration result

4.5.2.1 Room re-calibration

IR camera setups may change after a certain operation time; if e.g. movement of single

cameras due to mechanical instabilities cannot be excluded or thermal drifts occur. In

this case it is necessary to perform room calibrations periodically. DTrack2 provides a

simpliﬁed room calibration to revise an existing room calibration without need of an angle

tool, called room re-calibration.

Check the corresponding ﬁeld in the room calibration dialogue (see ﬁgure 4.36) to activate

re-calibration. Most settings have to be the same as during the previous standard room

calibration, therefore most values of the dialogue cannot be changed - settings regarding

the wand may be modiﬁed. If camera positions changed you would have to mark them

in the room calibration dialogue as ’moved’. Re-calibration is possible as long as camera

movements are not too large.

It will fail, e.g. if the mounting of cameras was changed. To perform a re-calibration, no

angle tool has to be present in the measurement volume; only the wand has to be moved

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4.5 DTrack2 frontend software

Figure 4.36: Room re-calibration dialogue

within the measurement volume in the same way as for a standard room calibration.

The main advantage of a room re-calibration is that DTrack2 preserves the origin of your

coordinate system and therefore, the orientation of the coordinate system as well.

Adding a camera to calibrated setup In order to add a camera to already calibrated

setup and preserve the origin of the room calibration, you proceed as follows:

•connect new camera to controller;

•wait until the camera is booted;

•within DTrack2 press ’F2’ in order to perform a search for new hardware;

•check if the camera has been recognized successfully (e.g., by opening camera

settings ’F7’);

•when starting measurement you must see the red message “(re-)calibration re-

quired!” on the Monitor 2DOF of corresponding uncalibrated camera (see sec-

tion 4.5.6.5 on page on page 120 for details);

•perform room re-calibration 4.5.2.1, new camera is automatically marked as “moved”

in the room re-calibration dialogue.

4 System setup

4.5.3 Body calibration

The process of teaching a target’s geometry to the tracking system is called body calibra-

tion. For a body calibration, the target (= rigid body) to be calibrated has to be in the ﬁeld

of view of the IR cameras. The number of bodies to be tracked has to be conﬁgured in

Settings →Body Administration.

After pressing Calibrate, the body calibration is started within ﬁve seconds delay. The

body can be moved during body calibration, always considering that the cameras should

see each marker of the body at the best.

If the body is not moved during the body calibration it should be considered that each

marker of the target has to be seen by at least two cameras and should be seen by

as many cameras as possible. If two markers, seen from one camera’s point of view,

are merging to one reﬂex, body calibration may be affected. These "merging marker

situations" should be avoided during body calibration, i.e. the target should be oriented

in a way that reduces merging markers to a minimum. The target orientation can be

checked before starting the body calibration, using DTrack2 ’s Monitor 2DOF display,

which is opened automatically in the background after selecting Calibration →Body. The

following ﬁgure 4.37 shows a rigid body with ﬁve markers that are all correctly seen by the

IR camera.

Figure 4.37: Recognized target in DTrack2 Monitor 2DOF display

Furthermore, the absence of any additional markers in the measurement volume has to

be ensured for body calibration. If additional markers that are not part of the target to be

calibrated are in the ﬁeld of view of the IR cameras during body calibration, these mark-

ers will be assigned to the target. That means, the target is not correctly calibrated and,

therefore, tracking problems may occur.

First, the target that shall be calibrated has to be selected in the select list Body. By de-

fault the ’type’ is set to standard which allows for calibrating a 6DOF target with spherical,

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4.5 DTrack2 frontend software

(a) Target type "standard" (b) Target type "5DOF"

Figure 4.38: Body calibration dialogue

ﬂat or active markers. When you are using a target made of ring markers you would select

the ’type’ according to the geometry of the target:

•’5DOF ’ .. a target made of spherical markers which are aligned along one main

axis. The rotation around that axis cannot be detected by the system - you loose

one dimension of freedom. Therefore, we call it 5DOF target.

•’5DOF (cylinder)’ .. a target made of ring markers which are aligned along one main

axis.

•’2x 5DOF (cylinder)’ .. an L-shaped target made of ring markers which delivers

6DOF data.

4.5.3.1 Selecting the coordinate system for 6DOF targets

The type of body calibration can be set as ’due to body’, ’due to room’ or ’due to room

(zero in marker)’. The difference between these calibration types is to be found in the

4 System setup

orientation of the body coordinate system relative to the body. During body calibration,

DTrack2 deﬁnes a local coordinate system (body coordinate system) for each target.

Body calibration setting due to body The body coordinate system is ﬁxed by the markers of

the rigid body according to a set of rules:

1. Search the biggest distance between two markers of the rigid body. These two

markers (# 1 and # 2) will deﬁne the X axis.

2. Search for a third marker (# 3) that has the smallest distance to one of the two

markers # 1 and # 2. The marker that has smallest distance to marker # 3 becomes

marker # 1. It will deﬁne the coordinate origin. The other marker will be # 2. The

positive X axis is directed from marker # 1 to marker # 2.

3. Marker # 3 deﬁnes the X/Y plane, together with markers # 1 and # 2. Marker # 3

has a positive Y coordinate.

4. The Z axis is already deﬁned by these rules, resulting in a right-handed coordinate

system.

(a) Body calibration

"due to body"

(b) Body calibration

"due to room"

"due to room (zero in

marker)"

Figure 4.39: Deﬁning the target coordinate system

Body calibration setting due to room The origin of the body coordinate system is set to the

center (center of gravity) of all markers building the rigid body. The axes of the body co-

ordinate system are parallel to the axes of the room coordinate system in the beginning

of the body calibration. I.e., the result of a body calibration will depend on the angular po-

sition of the target during calibration. A 6DOF measurement, following calibration without

having moved the body, will give the angular coordinates 0◦/ 0◦/ 0◦.

If the target was moved during calibration, the angular position of the target at the begin-

ning of the calibration will be taken.

Body calibration setting due to room (zero in marker) A combination of the ﬁrst two methods.

The direction of the axes of the body coordinate system will be set parallel to the room

coordinate system in the moment of body calibration - like done with setting due to room.

The origin of the body coordinate system is given by one marker of the body, according

to the rules given for setting due to body.

Chapter 4

4.5 DTrack2 frontend software

Selecting the coordinate system for 5DOF targets Analogue to the settings for the

standard targets it is also necessary to deﬁne the body’s coordinate system in case of

5DOF targets. The approach is a bit different but also straight forward.

Coordinate system setting for type ’5DOF’ and ’5DOF (cylinder)’In the body coordinate system

all markers of the target are on the selected axis. The origin is in the middle between the

two markers with the largest distance to each other. The orientation is deﬁned by the

marker with the smallest distance to the origin. Its position has a negative sign. The other

two directions are undetermined due to the one degree of freedom.

Coordinate system setting for type ’2x 5DOF (cylinder)’The body is expected to consist of two

connected 5DOF targets with a roughly perpendicular and constant angle in between.

These are placed on the two axes. The origin is placed at the position where the two

5DOF targets intersect. The ﬁrst axis is assigned to the 5DOF target which includes the

marker with the largest distance to the origin. The other 5DOF target is placed in the

plane created by the two axes.

A click-type torque wrench is one the most prominent members of this class of bodies.

Due to the engineering backlash and other high mechanical tolerances in these devices

often times the resulting body calibrations are error-prone.

ZPlease double-check whether all markers of the rigid body have been

recognized.

Then, conﬁrm the result with OK . If this is done, the geometry data of the calibrated target

will be stored in the Backend.

iAfter a new room calibration or room re-calibration it is not necessary

to perform a new body calibration. Only if the body itself changes you

have to calibrate the body again.

ZThe previous body calibration will be lost if you carry out a new body

calibration. If you want to save the previous body calibration please

use the ’Save ﬁle(s)’ option in the Body calibration dialogue.

4.5.3.2 Calibration with a calibration ﬁle

After successfully calibrating a body the information (i.e. geometry) is stored inside the

ART Controller in your personal conﬁguration (see also 4.5.6.2 on 95). To easily create

backups of calibrated bodies, calibration ﬁles can be saved at a desired location on the

remote PC. These ﬁles contain the dimensions of the target and the distances between

all markers. Each ﬁle is speciﬁc for just one type of target.

Press ’Save ﬁle(s)’ option in the Body calibration dialogue to store the calibration ﬁle(s) of

the currently used bodies.

Optionally a restricted visibility can be deﬁned for each marker of a body. This is per-

formed setting up so called “emission cones”; a 2DOF observation from a camera has to

be inside this cone to be used later for pose estimation. Currently the only way to equip

4 System setup

markers with emission cones is to import an appropriate calibration ﬁle; those are avail-

able on request. These ﬁles are created at ART on site performing a body calibration in a

deﬁned environment or measurement volume respectively.

Press Load ﬁle(s) (see ﬁgure 4.40) and choose the calibration ﬁle(s) for your targets. The

format of the ﬁle name has to be according to "standard b01.txt" - the identiﬁer "b01"

refers to the ID of the target. DTrack2 automatically assigns the calibration ﬁle to the

respective target by using the identiﬁer in the ﬁle name. Press ’Load’ again to conﬁrm the

import of the body calibration ﬁles.

Figure 4.40: Import of calibration ﬁles

ZThe previous body calibrations will be lost if you load new calibration

ﬁles.

iInvalid or corrupt ﬁles are not loaded by DTrack2 . This is indicated by

an error message in the conﬁrmation dialogue.

In the upcoming window (see ﬁgure 4.41) the coordinates of all identiﬁed markers are

listed together with the body’s label as well as the number of markers.

Figure 4.41: Body Calibration Result

By clicking Show details additional information can be displayed.

•’Distances’ shows all possible combinations of distances for all markers (min. dis-

tances are important for customer-speciﬁc geometries, call ART for further informa-

tion)

•’Emissions’ shows normalised emission vectors x, y, z and emission aperture for

bodies with restrictions of visibility (calibration ﬁles available on request by ART )

•’Cylinder’ shows coordinates and radii for bodies with (cylindrical) ring markers

4.5.3.3 Body re-calibration

DTrack2 provides a possibility to re-calibrate a rigid body in case its geometry is affected

due to e.g. mechanical impact. Tick the checkbox re-calibation and perform a routine

Chapter 4

4.5 DTrack2 frontend software

body calibration as described in 4.5.3 on page 84.

iOnly during a re-calibration the origin and orientation of the initial co-

ordinate system, as well as speciﬁc information (predeﬁned emission

vectors, cylindrical marker) are preserved.

4.5.3.4 Target Library

With the introduction of DTrack2 v2.8.1 it is possible to make use of an integrated library

that contains calibration data for most ART standard targets (e.g. Motion Capture, glasses

targets, etc.). When you go to Calibration →Body choose ’Target Library’ (refer to ﬁgure

4.42). The ﬁlter is set to ’Found Targets’ by default whereas the other options may be

used in case only targets of this type are to be calibrated (e.g. Motion Capture).

Figure 4.42: Calibrate bodies with the target library

With the ’Found Targets’ ﬁlter all targets presented, i.e. shown to the system, will be

found. In the unlikely case that a target is not found by the system it needs to be cal-

ibrated using the standard body calibration. The calibrations for all found targets only

need to be accepted either by ticking the checkbox ’accept all’ or one at a time. Finalize

the assignment of the targets by pressing ’Apply’.

DTrack2 compares the geometry of the physical target with the calibra-

tion data of the target library. In some cases a re-calibration might be

necessary, e.g. when a clip-on target is applied to the glasses bending

is possible.

If you haven’t increased the number of targets before the system will ask you if this number

should be adjusted automatically. Press ’OK ’ if you want the system to do so.

Typical usecase: Motion Capture targets without Inertial sensors For this descrip-

tion we’re assuming that a room calibration for eight cameras has already been carried

4 System setup

out and that the "full-featured" or "max. 8 cameras" license is available.

First, ﬁt the targets to the test person and make sure that the person is in the calibrated

volume. Then, start the calibration (Calibration →Body →’Target Library’→’Calibrate’)

and allow the test person to move around. While this movement the targets must be visi-

ble for the tracking system.

Finally, one after the other target should be recognized and appear in the display. Tick the

checkbox ’accept all’ and start the measurement in order for your application to receive

tracking data.

In case you need to adjust the order of the targets please go to Settings →Body Admin-

istration (F8).

4.5.4 Body adjustment

The Body adjustment function (see ﬁgure 4.43) is a tool to visualise and manipulate cal-

ibration data of rigid bodies, i.e. the body coordinate system may be changed relative to

the markers of the body.

iBody adjustment is not available for 5DOF targets or measurement

tools.

Figure 4.43: Body Adjustment

The main features of Body adjustment are:

Chapter 4

4.5 DTrack2 frontend software

•adjust the body coordinate system of each target within the DTrack2 frontend,

•online mode (i.e. the 3D-representation of the target in the ’Graphic view’ is depict-

ing movements / rotation of the target in the "real world"),

•visualise (optionally) predeﬁned emission cones due to restrictions of visibility (di-

rectional and angular dependence) for all markers

•aligning the axes of body and room coordinate system without changing the origin,

•use predeﬁned body coordinate systems,

•move the origin of the body coordinate system,

•set the origin of the body coordinate system in a selected marker,

•delete selected markers from the target geometry.

For detailed information please refer to chapter 4.5.6.4 on page 117.

4.5.5 Filtering options in DTrack2

With the DTrack2 release v2.9.0 we introduce highly improved ﬁltering options which

allow for ideal settings according to the requirement for the tracking performance. For

example in applications where reference targets are used to get the position of a seating

buck it is now possible to apply a strong ﬁlter for this speciﬁc target which results in abso-

lutely static tracking data.

Using three main settings for deﬁning a ﬁlter, i.e. strength, prediction and mode, it is

possible to customize the tracking behaviour in general or for single targets according to

the requirements. Following, a description of these settings.

4 System setup

Setting Description Usage

Strength Sets the strength of the ﬁlter. Low values

mean less ﬁltering with faster reaction but

higher jitter. High values mean stronger ﬁl-

tering with smoother output but slower re-

action.

a strong ﬁlter may be ideal for

tracking seating bucks

Prediction Predicts output for the speciﬁed time in the

future to compensate tracking and render-

ing latency. Note that too high positive

values can increase jitter and reduce pre-

cision. Negative values can be used for

smoothing the output at the cost of higher

latency.

a "negative" prediction may be

ideal for recording data as la-

tency doesn’t matter so much

Mode Speciﬁes the elementary behavior of the ﬁl-

ter. Several options are available.

−

’Adaptive fast’ Automatically adapts to the observed mo-

tion.

Moving targets that change be-

tween fast and slow motions,

such as Flysticks.

’Adaptive slow’ Automatically adapts to the observed mo-

tion, with stronger ﬁltering of fast motions.

Moving targets with slow and

medium motions

’Fast’ Optimized for fast motions without special

ﬁltering of slower motions.

Targets where quick reaction is

important, such as HMDs.

’Slow’ Optimized for medium motions without spe-

cial ﬁltering of slow motions.

Targets where quick reaction is

important, but motions are slow.

’Static’ Optimized for targets that are known not to

move at all.

Reference targets attached to

non-moving objects

’Reference target’ Optimized for generally static objects, with

automatic detection of occasional motions.

Reference targets attached to

occasionally moving objects.

Chapter 4

4.5 DTrack2 frontend software

4.5.6 Menu structure

4.5.6.1 Overview

DTrack2 Shortcut page 94

Licenses License overview →Licenses can be added by entering

a license key (for Fingertracking, for the Measurement

Tool or for Cascaded Systems)

Conﬁgurations Create and save different conﬁgurations, lock the used

conﬁguration and save its settings

Start/Stop M Start/Stop measurement

Search hardware F2 Search for newly added hardware

Controller standby Force the controller to go into standby mode

Controller reboot Reboot the controller

Quit Q Quit DTrack2

Settings Shortcut page 97

Cameras F7 Camera settings

Synccard Synccard settings

Inertial Sensor Settings for intertial sensors

ART Radio Info Opens a dialogue where you can see available

transceivers and devices within your setup

Tracking General settings

Body Administration F8 General settings for all targets and interaction devices

Output F9 Set output channels and conﬁgure the data to be trans-

mitted

Fingertracking Conﬁgure your Fingertracking or Tactile Feedback de-

vice

Flystick Conﬁgure your Flystick

Measurement Tool Conﬁgure your Measurement Tool

Controller Conﬁgure the controller for your local network

Cascaded System Conﬁgure a Cascaded System with available con-

trollers

Calibration Shortcut page 111

Start static reﬂex scan for all

enabled cameras

Starts the static reﬂex scan

Inertial Sensor Calibration Re-calibrate the internal sensors of the inertial sensor

Room F5 Room calibration

Room adjustment Shift + F5 Adjust room coordinate system

Body F6 Body calibration

Body adjustment Shift + F6 Adjust body coordinate system

Hybrid Body Determine the relative rotation between optical and in-

ertial sensor

Fingertracking Start calibration process for Fingertracking (i.e. hand

geometry)

Measurement Tool Start tip calibration process for the Measurement Tool

4 System setup

Display Shortcut page 120

Monitor 2DOF Graphical display of markers recognized by the cam-

eras (monitor 2DOF view)

Data F10 Display measurement results (6DOF and/or 3DOF)

Fingertracking Display Fingertracking measurement data

Flystick Display Flystick measurement data

Measurement Tool Display Measurement Tool data

Events Display event messages generated by DTrack2

Set to default Reset the shown displays to default

Tools Shortcut page 124

Controller Update Start the assistant for the controller update

Measurement Tool demo Provides a convenient way to perform measurements,

either by pressing a button or by performing a gesture

with the Measurement Tool

About Shortcut page 124

DTrack2 Frontend software version

Controller Backend software version

What’s new? Overview of the new features

What’s this? Shift + F1 Help

Table 4.7: DTrack2 menu structure overview

4.5.6.2 Menu DTrack2

DTrack2 Shortcut

Licenses

Conﬁgurations

Start/Stop M

Search hardware F2

Controller standby

Controller reboot

Quit Q

Table 4.8: Menu DTrack2

Licenses The capability of the tracking system is deﬁned by licenses which can be

managed here. You can add functionality for Fingertracking, the Measurement Tool or

Cascaded Systems by simply entering a license code which can be provided by ART (see

ﬁgure 4.44).

If you want to add Fingertracking, for example, go ahead as follows:

Chapter 4

4.5 DTrack2 frontend software

•Select the feature Fingertracking.

•Click on Hardware Info.

•Contact ART and communicate the serial number of the synccard or the MAC ad-

dress of the Ethernet port (=Identiﬁcation) in order to receive a license code.

•Enter the license code you received from ART in the ﬁeld new license code.

•Click on Add license.

(a) Licenses overview (b) Hardware information

Figure 4.44: Managing the licenses

The process is the same for other modules.

Conﬁgurations It is possible to create different conﬁgurations, e.g. with different tar-

gets or ﬂash settings. These are related to the name of the user and, thus, are easily

accessible.

When creating a new conﬁguration you need to describe your conﬁguration in a few words

(→’description’) and enter your name (→’owner’). The conﬁguration can be changed

later on with Edit (see also ﬁgure 4.45).

Your personal conﬁguration is created using the values of the current conﬁguration (→

’clone current conﬁguration’) or default values (→’create with default values’), respec-

tively:

•’clone current conﬁguration’:

all existing calibrations (room and body calibration) and ﬂash settings are inherited.

•’create with default values’:

the system will start from scratch - i.e. as manufactured. That means, you will not

have a room calibration or any body calibrations.

4 System setup

(a) Main window (b) Create a new conﬁguration

Figure 4.45: Managing the conﬁgurations

Just press Create and the conﬁguration is saved on the controller.

It is possible to protect the used conﬁguration by pressing the button Lock . Then, you will

be forced to enter a new password and your conﬁguration is locked.

ZPlease do not forget this password!

Existing conﬁgurations may be used by selecting the corresponding entry and clicking

Apply. Quit this dialogue by pressing Exit - the conﬁguration is loaded.

Existing conﬁgurations can be deleted if not in use any more. Select the entry to be

deleted and click Delete.

Log settings saves the selected conﬁguration in a text ﬁle which can be saved on the

remote PC. This function is mainly intended for supplying information to ART in case a

problem arises.

From DTrack2 v2.8.1 it is possible to export and import conﬁgurations. ’Save’ will export

the complete active conﬁguration. ’Load’ imports previously saved conﬁgurations. The

imported conﬁguration will automatically become the active conﬁguration. It’s possible to

import several conﬁgurations at a time.

Please refer to chapter 6.1 on page 147 for detailed information.

Chapter 4

4.5 DTrack2 frontend software

When you export a conﬁguration please make sure that you rename it

before exporting, for example by adding the exporting date (e.g. "Stan-

dard 07122012"). Conﬁgurations with the same name (e.g. "Standard")

will be overwritten.

Start/Stop Start/Stop measurement.

Search hardware Search for newly added hardware and continue with the system setup

without the need of restarting the controller.

Controller standby Force the controller to go into standby mode with this command.

You can restart the controller by using Wake On LAN. Please refer to chapter 4.2.7 on

page 56 for more details.

Controller reboot Reboot the controller with this command.

Quit Quit DTrack2 frontend software - the active measurement doesn’t have to be

stopped.

4.5.6.3 Menu Settings

Settings Shortcut

Cameras F7

Synccard

Inertial Sensor

ART Radio Info

Tracking

Body Administration F8

Output F9

Fingertracking

Flystick

Measurement Tool

Controller

Cascaded System

Table 4.9: Menu Settings

Cameras This dialogue shows the information about the cameras connected to the sys-

tem and recognized by the software. It allows changes of ﬂash intensity and camera

orientation, as well as settings for modulated ﬂash - either globally for all cameras or

individually. The modulated ﬂash may only be used with active targets. It is used to syn-

chronize an active target.

Changes to the following settings can be made either for all cameras at once, or for each

camera separately. Each camera is represented by a single tab within this window.

4 System setup

Room calibration In tab “All Cameras” the “Room cal” column shows which cameras were

used during the room calibration. The ‘yes’ value means that in the latest room calibration

the coordinates of this camera are known. If the camera was not present during the latest

room calibration, this value is ‘no’ and this camera must be re-calibrated to contribute to

the tracking (see section 4.5.2.1 on page 83 on how to add a new camera).

It can also happen that the camera was present during the room calibration, but is not

present anymore (e.g., due to disconnected cable). Such cameras are greyed out and

the only data available are camera type and serial number.

DTrack2 is able to operate although cameras are missing or need to

be (re-)calibrated; for best performance it is highly recommended to

resolve any issues that prevent all available cameras contributing to

the tracking.

Reﬂex suppression DTrack2 is capable of suppressing reﬂexes (e.g. sunrays on the ﬂoor)

in a static way. However, reﬂex suppression should always be the last option to be con-

sidered. If possible try adjusting the cameras in order to minimize reﬂexes. Please refer

to chapter 4.5.1.7 on page 76 for more details.

ZYou should always be aware that reﬂex suppression results in remov-

ing of the area, in which the reﬂex originated, from the tracking volume.

There are two possibilities to carry out a reﬂex suppression:

1. Mark the checkboxes for each camera when you want to suppress reﬂexes. Af-

terwards, select Calibration →Start Static Reﬂex Scan for all enabled cameras to

make sure that static reﬂexes will be suppressed.

2. While measurement is running you may deﬁne the areas to be suppressed manu-

ally. In the Monitor 2DOF display, right-click on the respective camera window and

enable ’Edit reﬂex suppression areas’. Alternatively, you may use the shortcut (’E’)

to enable this mode (shown in ﬁgure 4.46(a) on page 99).

Within the edit mode you may (also refer to ﬁgure 4.46(b) on page 99)

•create new areas,

•delete areas,

•clear regions,

•resize areas and

•move areas.

Reﬂex suppression areas are enabled when you leave the edit mode (by disabling

’Edit reﬂex suppression areas’) and accept the changes. The single areas deﬁned

are stored in the controller and can be edited each time you enter this mode.

Chapter 4

4.5 DTrack2 frontend software

(a) Reﬂex suppression edit mode (b) Reﬂex suppression edit mode help

If you want to disable all reﬂex suppression areas for a camera at the same time,

just right-click on the respective camera and deactivate the option ’Active’.

Flash settings The ﬂash intensity may be changed within an interval of

•0 .. 6 for ARTTRACK1 ,

•0 .. 8 for ARTTRACK2 /ARTTRACK3 ,

•0 .. 100 for ARTTRACK5 ,ARTTRACK5/C and TRACKPACK/E

•0 .. 7 for TRACKPACK .

When using ARTTRACK2/C cameras, it is not possible to adjust the

ﬂash intensity of the respective external ﬂashes with the DTrack2 fron-

tend software!

Please contact ART in case you need to adjust the ﬂash intensity of

the external ﬂashes.

These settings strongly depend on the working area and range. If you have a small work-

ing area where you are close to the cameras small ﬂash intensities may be sufﬁcient.

Otherwise, if your working area is far away from the cameras (but still within tracking

range of the cameras) it may be necessary to change to greater ﬂash intensities.

Generally speaking, you should adjust the ﬂash settings in a way that the recognized

markers are coloured in green or yellow.

4 System setup

Keep a distance of min. 20 cm when operating the cameras ! All cam-

eras are assigned to the Exempt Group according to IEC62471-1 and

therefore pose no risk or hazard to the human eye or skin at this dis-

tance.

To be on the safe side, always double-check if the markers of the target are seen properly

by the cameras. Therefore, please use the Monitor 2DOF view:

•markers coloured in red are characterized by bad circularity, small size or low inten-

sity; this may result in poor tracking quality

•markers coloured in yellow offer a good tracking quality

•markers coloured in green offer a very good tracking quality

Increase the ﬂash intensity until all markers are yellow or green (recommended).

Syncgroup For ARTTRACK5 ,ARTTRACK5/C and TRACKPACK systems it is possible

to conﬁgure the syncgroups via software. You may change the syncgroups either on the

All Cameras tab or on the one of the respective camera. Possible values are ’Channel 1’,

’Channel 2’ or ’Channel 3’. These settings correspond to the three syncgroups which can

be setup via hardware (daisy-chain cabling) for ARTTRACK systems.

Global camera mode (ARTTRACK5 ,ARTTRACK5/C and TRACKPACK/E only) To switch the cam-

era mode, select the appropriate entry e.g. 1.3 Mpix, max. 150 Hz. Dependent on your

application needs, this function can give you access to:

•higher frame-rates

•lower latencies, i.e delay times (approx. 5 ms @ 0.5 Mpix) Please refer to chapter

A.6 on page 199 for more details.

by selecting smaller ﬁeld of views.

Be aware, that higher frame-rates come at the cost of the cameras’ reduced ﬁeld of view

as well as a limited amount of targets that can be tracked simultaneously (lesser amount

of targets @ 300 Hz). The max. frame-rate is deﬁned by the camera with the largest

ﬁeld of view respectively the max. frame-rate of that individual camera. In mixed systems

ARTTRACK2 or ARTTRACK3 &ARTTRACK5 the max. possible frame-rate is always

limited to 60 Hz.

Global display intensity (ARTTRACK5 only) If necessary the brightness of the status LEDs

and the 2-digit LED matrix display can be dimmed from 0...100%, e.g. when used in

light-sensitive environments (global setting or individually).

Global display mode (ARTTRACK5 only) By default the status LEDs are activated, while the

2-digit LED matrix display shows the currently assigned camera ID. Alternatively select

number of markers / camera ID to display the number of markers in the camera’s ﬁeld of

view during measurements. The 2-digit LED matrix display can also be deactivated by

selecting only status LEDs (global setting or individually).

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4.5 DTrack2 frontend software

Modulated ﬂash The ART tracking system can be used with active markers, i.e. mark-

ers consisting of infrared LEDs instead of retro reﬂective material (e.g. Fingertracking,

see chapter 5.3 on page 137). This allows both, more robust and longer ranging targets.

These LEDs do not light continuously but also emit light ﬂashes like the camera ﬂash and

thus have to be synchronized with the camera’s timing. This can either be achieved by a

synchronization cable or by using a modulation on the ﬂash.

The option modulated ﬂash, which only appears on the All Cameras tab, allows selecting

one of the cameras to emit the coded ﬂash that triggers active targets. Only one camera

can emit the modulated ﬂash. The modulation reduces the ﬂash intensity in lower ﬂash

settings, so it might be necessary to increase the ﬂash intensity. In higher settings the

reduction is insigniﬁcant.

The camera which emits the modulated ﬂash has to be in syncgroup

# 1 ! For ARTTRACK systems this means that the camera has to be

connected to the OUT1 output of the Synccard2. TRACKPACK systems

may be conﬁgured via software (refer to chapter Syncgroup above).

Display upside down The checkbox display upside down speciﬁes how the ART camera is

mounted (upright or upside down). This setting does not have any inﬂuence on the correct

working of the tracking system because the orientations of the cameras are correctly

determined by the photogrammetric algorithms in any case.

Details Here, it is possible to change the settings concerning markers:

Description

’global marker mode’ conﬁgure the marker detection

’global maximum number of markers’ maximum number of markers that a camera is allowed

to see

’global maximum size of markers’ maximum display size of a marker on the sensor

’global minimum size of markers’ minimum display size of a marker on the sensor

Synccard This dialogue shows the model and the serial number of the synccard. Fur-

thermore, it offers a dropdown list to select the mode of synchronization.

Basically, you can select between internal and external synchronization. The further dif-

ferentiation is shown in table 4.10.

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4 System setup

supported synccard mode ﬁeld of application

internal generated signal (50 up to 300Hz ARTTRACK5 )

external video signal active-stereo projection with an

analogue video sync signal (=VGA)

external video signal, for validated shutter glasses 1

external video signal, for validated shutter glasses, divisor 2 2

external TTL signal active-stereo projection with a TTL

sync signal

external TTL signal, for validated shutter glasses 1

external TTL signal both edges 3

external TTL signal both edges, for validated shutter glasses 1 3

direct settings advanced custom settings

1predeﬁned settings that should be used with the shutter glasses mentioned in table 4.11

2if, additionally, the frequency of the external synchronization signal is greater than 60Hz, this mode

should be used

3available only for Synccard3

Table 4.10: Overview of the supported synccard modes

If you select ’direct settings’ you may use advanced options for conﬁguring the synccard:

Option Description

source conﬁgure the type of synchronization to be ’internal’, ’video’,

’ttl’, ’ttlinv’ or ’ttlboth’

frequency [Hz] change the frequency in an interval of 10 Hz up to 300 Hz

(only for internal synchronization and dependent on camera

mode when using ARTTRACK5 or TRACKPACK/E !

divisor for external signal reduce the tracking frequency (only for external synchroniza-

tion!)

Delay [us] conﬁgure the delay between the syncgroups

Brand Type

RealD CrystalEyes 1, 2, 3, 5

NuVision APG6000, APG6100

XPand X101, X103 (with NuVision Long-Range Emitter), X104LX

NVidia 3D Vision Pro (RF sync’ed)

Volfoni EDGE (with Volfoni or NuVision LR Emitter)

Virtalis ActiveWorks 500

Table 4.11: Overview of validated shutter glasses

Inertial Sensor In this dialogue all available wireless transceivers (dongles) are shown.

Furthermore, it is possible to set the frequency the sensors are operating at (default: 100

Hz). Additionally all inertial sensors that have been previously added to the DTrack2 con-

ﬁguration are listed with the following properties:

•Device ID + wireless icon

•Model (e.g. Colibri Wireless)

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Chapter 4

4.5 DTrack2 frontend software

•Name (targets from Hybrid Motion Capture suit or user-deﬁned)

•Firmware Version

•Currently used channel (default: 35 / 55)

•Wake-up mode (radio, tapping, USB/button)

•Battery level

•Temperature (only during measurement)

The default channels for all dongles and sensors are 35 and 55. In

case these WLAN frequencies are already occupied by other devices

in range, connection problems may occur. ART recommends to scan

for available channels and to select free channels accordingly. Keep a

minimum distance of 10 channels between dongles or from otherwise

unavailable channels for optimum connectivity.

ZFor optimal battery life, ART recommends to switch all sensors to

wake-up mode "USB/button" when not in use for a longer period of

time.

For more information, please refer to chapter 4.4 on page 63.

ART Radio Info When you are using a Flystick, for example, you will get information

about the used transceiver and the Flystick device itself. The following information is

offered:

Description

’Model’ the model of the transceiver or the device respectively

’Serial’ the serial number

’Version’ the ﬁrmware version

’Is free (only for Devices)’ the device is not free (= ’no’) if it is assigned to an interaction

device ID

’Is present’ the device or the transceiver is present in the tracking volume

By clicking the button Show details the current channel of the radio transceiver is shown.

By default the radio transceiver is automatically selecting a radio channel during booting.

You may also select an appropriate channel manually using the drop-down menu ’set

channel number’. The setting is saved persistently.

Tracking In this dialogue you can conﬁgure whether 3DOF markers are calculated or

not and you can enable or disable the ’automatic start of measurement after booting’.

Also, you can globally deﬁne the ’central axis’ for all 5DOF targets. For these the rotation

around the body axis cannot be measured by the tracking system. This rotation is there-

fore set to a certain value by the system. Thus, the 5DOF central axis is only important if

you intend to use the rotation around the body axis. The most important properties are:

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4 System setup

•If the 5DOF body is positioned parallel to the 5DOF central axis the rotation around

the body axis remains undetermined.

•The rotation around the body axis is reduced to a minimum.

We recommend that you choose the 5DOF central axis as the direction which is the least

often parallel to the tracked body axis (e.g. ﬂoor to celling for glasses targets).

iThe best choice for the 5DOF ’central axis’ may be found when using

the tracking data in your appplication.

Details of the deﬁnition:

In addition to the 5DOF central axis the system selects an axis for each body in the body

coordinate system (i.e. "pulled axis"). The rotation around the body axis is set to the value

minimizing the angle between the pulled axis and the 5DOF central axis. The pulled axis

is always perpendicular to the body axis. In addition the following criteria are used:

•If the 5DOF central axis is not the body axis the pulled axis is the axis minimizing

the angle to the 5DOF central axis.

•If the 5DOF central axis is the body axis the pulled axis has a random direction in

the plain.

The ’automatic restart of measurement after loss of sync signal’ option is set to ’active’

by default and therefore, it is not shown anymore (from DTrack2 v2.8.1).

Body Administration The menu allows for administering all targets (e.g. Standard,

Flystick, etc.) in the system (refer to ﬁgure 4.46).

The number of 6DOF bodies represents the number of targets that should be tracked. In

this context, the number of targets does not include the interaction devices (e.g. Flystick,

Fingertracking or Measurement Tool ). These are completely conﬁgurable in separate

tabs.

iHowever, the maximum total number of bodies that may be used in

ART systems includes the calibrated interaction devices (Fingertrack-

ing, Flystick, Measurement Tool )!

Here, you can activate, delete or reset target calibrations and change the order of the

single targets. Additionally, you get the information by which means the target has been

calibrated:

•’Custom’ means that the standard body calibration has been used.

•’Target Library’ means that the predeﬁned calibration ﬁle from the system has been

used.

For a detailed description of the single actions please refer to table 4.12.

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Chapter 4

4.5 DTrack2 frontend software

Figure 4.46: Flexible Body Administration (from DTrack2 v2.9.0)

Action Description

’Active’ Activate or deactivate a target. Data of deactivated targets will not be

transmitted in the data stream. The target order will not be affected.

’Delete’ Deletes the calibration of a target - effective immediately after conﬁrm-

ing the security query. The target order will not be affected.

’Reset’ In case the target has been calibrated initially with the ’Target Library’

and re-calibrated later by the user, it is possible to reset the calibration

to ’Target Library ’.

’Change order’ With the arrows on the right-hand side of the window you may change

the order of the targets. The data output will change accordingly.

Table 4.12: Body Administration - Detailed description of the actions

As mentioned before you can administer interaction devices as well. Therefore, you may

use the tabs Flystick,Measurement Tool and Fingertracking.

In the bottom right of the dialogue you will ﬁnd four buttons:

105

4 System setup

Button Description

’Filter’ Activate or deactivate the ﬁlter for each target. You can either use de-

ﬁned presets or customize it to your requirements. A detailed descrip-

tion of the ﬁltering options can be found in chapter 4.5.5 on page 91.

’Calibration’ Directly access the Body Calibration dialogue and perform the calibra-

tion for the selected target. A detailed description for body calibration

can be found in chapter 4.5.3 on page 84.

’Hybrid Body

Calibration’

Directly access the Hybrid Body Calibration dialogue and perform the

calibration for the selected hybrid target. A detailed description for hy-

brid body calibration can be found in chapter 4.4 on page 66.

’Body Adjust-

ment’

Directly access the Body Adjustment dialogue and perform the neces-

sary adjustment for the selected target. A detailed description for body

adjustment can be found in chapter 4.5.4 on page 90.

Output The dialogue Output determines the settings of data output via Ethernet. Data

output will be enabled when you tick the checkbox active.

Figure 4.47: Output settings

Identiﬁer Description

fr frame counter

ts timestamp

6dcal number of adjusted bodies

6d 6DOF standard body

3d 3DOF marker

6df2 Flystick

6dmt Measurement Tool

6dmtr Measurement Tool reference

6dmt2 Measurement Tool (also for ball

probes)

gl Fingertracking hand

glcal number of calibrated Fingertracking

hands

6di 6D inertial body

6df Flystick (old)

only available if activated in Flystick

settings (→checkbox ’use old output

format’)

Table 4.13: Output identiﬁers

ZWhen using the ’timestamp’ please note the remarks on accuracy in

chapter B.2.2 on page 211.

In total, up to 5 UDP channels for DTrack2 data output can be conﬁgured. Tick the check-

box this computer to send data to the remote PC you are currently working at. If you want

to send data to any computer within your local network just enter the IP address of the re-

ceiver and a port number. In addition, it is possible to deﬁne a multicast output. By ticking

this checkbox the UDP data is sent to a group of addresses in the range of 224.0.1.0 to

239.255.255.255.

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In order to reduce the data of the UDP output data stream you may set the ’send data

divisor’ to values from 1 to 10. The numbers have the following meaning:

•1 .. every frame is transmitted,

•2 .. every second frame is transmitted,

•...

•10 .. every tenth frame is transmitted.

The UDP output data may be routed by DTrack2 by ticking the checkbox act as router

for tracking output. This functionality is especially important for customers where it is not

allowed to connect the controller to their local network due to security reasons.

(a) act as router enabled (b) act as router disabled

The mandatory requirement to use this function is that the PC, where DTrack2 is installed,

needs to have two separate Ethernet plugs: one for connecting to the controller and one

for the respective local network. The DTrack2 frontend reads the data from the controller

and routes it to the local network where the application PC is connected to.

iUsing this function will cause a short delay during forwarding of the

data.

ZDo not use this function if the application PC and the controller are in

the same network!

Please refer to chapter B on page 203 for the format of the data output.

Fingertracking Here, you can deﬁne the number of hands to be used (values: 0 ..

4). Based upon this value, the correct number of selected hands is shown. By default,

the hand geometry is ’none’ and the ﬁeld Simulate 5 Fingers is empty until you carried

out a calibration of the ﬁngers (→hand geometry). Then, the hand geometry will change

into the name you deﬁned during calibration of the ﬁngers. If you are using a three ﬁnger

thimble set but want to get output data for ﬁve ﬁngers you may tick the checkbox 3 ->5.

The software DTrack2 will move the two missing ﬁngers parallel to the third ﬁnger.

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4 System setup

It is possible to save several hand geometries in DTrack2 - these will appear in available

hand geometries. So you can use your Fingertracking set with different people and, most

important, you need to calibrate the Fingertracking set only once for each person.

From DTrack2 v2.8.1 on it is possible to export (’Save’), import (’Load’) and remove

(’Delete’) available hand geometries. Just press ’Save’ and select the hand geometries

you want to export and save them at your desired location.

For importing a stored hand geometrie just press ’Load’ and change to the respective di-

rectory, select the appropriate ﬁle and press ’OK ’. The hand geometrie may now be used

as follows.

Now, just assign the desired hand geometry to the respective hand ID and use Finger-

tracking. Therefore,

•mark the respective hand ID,

•mark the desired hand geometry and

•press Select.

Repeat the steps if you want to use another hand.

Please refer to chapter 5.3 on page 137 to learn how to install Fingertracking.

Flystick In the Flystick Settings you can deﬁne the number of Flysticks to be used (max.

20).

Checkbox Description

’use old output format’ Use the output format of the old Flystick1 (see chap-

ter B on page 203)

’activate MultiUser function’ Refer to page 130 in chapter 5.1 for more informa-

tion.

’use head targets’ The data pair (Flystick and head target) of one user

is made available as output data (if MultiUser func-

tion is activated).

Table 4.14: Flystick settings - Description of the checkboxes

Below, there are two more properties which can be conﬁgured for Flystick3:

•sync groups:

Conﬁgure your active(!) Flystick3 to send out IR ﬂashes for one or more syncgroups

(syncgroup #1, syncgroups #1 and #2, . . . ; default = syncgroup #1).

•ﬂash intensity:

Set the ﬂash intensity of the active target of the Flystick3 (default = 3) by moving the

slider.

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If you change the number of Flysticks you will immediately recognize entries in the se-

lected Flysticks ﬁeld. The ﬁelds Model,Serial and Port are empty by default.

Make sure that your Flystick is in the available Flysticks list - if necessary, compare the

serial number listed here to the one printed on the battery compartment of the Flystick2 or

on the back cover of the Flystick3. Now, you have to assign your Flystick to the respective

Flystick ID.

Therefore,

•mark the respective Flystick ID,

•mark the desired available Flystick and

•press Select.

Repeat these steps if you want to use another Flystick. Please refer to chapter 5.1 on

page 126 to learn how to install the Flystick2 and refer to chapter 5.2 on page 132 for the

Flystick3.

There are one or two Flystick1 entries in the list available Flysticks, even if no Flystick1

is present in the volume. This is due to the fact that the Flystick1 connects via serial

COMport which cannot be polled automatically. If you are using a Flystick1 please refer

to the Flystick1 manual.

Measurement Tool Within the Measurement Tool dialogue you may deﬁne the number

of Measurement Tools and the number of references. It is limited to a total number of

four each.

Below, there are several ﬁelds where you may change the default values within the allowed

ranges to suit your application.

Control Description

’number of Measurement Tools ’ conﬁgure the number of devices to be used

’number of references’ conﬁgure the number of reference bodies to be used

’measurement duration [s]’ conﬁgure the time to perform a measurement with

the Measurement Tool (valid range: 0.2 - 10.0 sec)

’tool tip tolerance [mm]’ specify the range within which the tip is assumed to

be static (valid range: 0.1 - 5.0 mm)

’activate measurement start simula-

tion’

activate the start button simulation and enable the

respective controls

’minimal angular variation [deg]’ specify the minimum angle that the Measurement

Tool has to be tilted over to start a measurement

(valid range: 10◦- 120◦)

’maximum lead time for this angular

variation [s]’

waiting time before the measurement start by the

start button simulation

Table 4.15: Measurement Tool settings

If you are working with a reference body you may assign it to a speciﬁc ’Measurement

Tool ID’:

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4 System setup

•mark the respective Measurement Tool ,

•mark the reference body and

•press Select.

Repeat these steps if you want to assign references to other Measurement Tools .

Please refer to chapter 5.4 on page 144 to learn how to install the Measurement Tool .

Controller The menu for the Advanced Controller Settings is divided into two tabs - Net-

work and Time.

On the Network tab you may change the hostname (not recommended!) and the domain

according to your network guidelines. When the network cable has been plugged into the

controller while booting, the controller is a DHCP client and the checkbox is ticked. If the

network cable is unplugged while booting the controller uses its default IP address (i.e.

192.168.0.1).

You may also specify IP address,subnet mask,gateway and nameserver as desired.

The MAC address of the controller is printed in the last line for your information (ethernet-

MAC LAN).

On the Time tab you can set the UTC time of the controller. Furthermore, you can syn-

chronize the UTC (=Universal Time Coordinated) time using NTP (=Network Time Proto-

col). NTP is a protocol designed to synchronize the clocks of computers over a network.

Tick the checkbox activate NTP and enter hostname or IP address of your server.

If NTP is activated the controller is trying to connect to the NTP server repeatedly in or-

der to update its clock. The values for ’reachability’ range between 0% - 100% (typically).

They are a measure for the quality of the reachability of the NTP server. Only NTP servers

which are contacted over the internet may provoke some problems. The quality of the syn-

chronization of the clocks is indicated with ’estimitated precision’ in the unit milliseconds

(=ms).

iSynchronizing with NTP takes quite a long time. Active measurements

won’t be disturbed.

Cascaded System Cascading means that two or more stand-alone tracking systems

are combined to one large system in order to have only one consolidated data out-

put. It is possible to cascade TRACKPACK/E systems with or without ARTTRACK5 and

ARTTRACK5/C and to build cascades out of ARTTRACK (discontinued) with TRACK-

PACK systems (discontinued). Therefore, the system is subdivided into one master and

up to eight slaves. However, the total number of cameras in the cascaded system cannot

exceed 16 for TRACKPACK/E only systems and 50 for combined ARTTRACK5 &ART-

TRACK5/C and TRACKPACK/E systems respectively.

The task of the master is to gather all single data outputs from all slaves and to merge

them into one single data output. The DTrack2 frontend connects to the master only and

allows to conﬁgure (e.g. cameras, output, tracking, etc.) the entire tracking system as

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usual.

The master has to be an ARTTRACK Controller with "full-featured" li-

cense (< DTrack2 2.10) and a Synccard2.

Starting with DTrack2 version v2.10 a new license model has been es-

tablished. The master controller needs to have a dedicated "cascaded

systems" license as well as a sufﬁcient license for ALL cameras in the

cascade, e.g. 4 ARTTRACK5 + 4 TRACKPACK/E cameras = license for

8 cameras.

In order to conﬁgure the cascaded system you have to start the DTrack2 frontend soft-

ware and establish a connection to the master.

Go to Settings →Cascaded System to enter the conﬁguration dialogue for the cascaded

system. Basically, you have the choice between ’scan LAN’ or entering a ’slave host-

name or IP address’ directly. For the latter one, you need to know the hostname or the

IP address of your slave(s) when using DHCP or in case you have set a speciﬁc static IP

address. The button ’Update’ refreshes the list.

On the right-hand side of the dialogue you will be presented a list of ’Available’ controllers

(i.e. which can become a slave in the cascaded system). Mark the desired controller

and press the button ’Select’ to assign this controller to the cascaded system. It will then

appear on the left-hand side of the dialogue in the list of the ’Selected’ controllers.

Mark controllers in the list of the ’Selected’ controllers to remove them from the cascaded

system by clicking the button ’Deselect’.

If the checkbox ’wake on LAN’ is ticked, all connected slaves will go to standby mode or

reboot if the master goes to standby mode or reboots.

Refer to chapter 4.3 on page 58 for more information on the cascaded system.

4.5.6.4 Menu Calibration

Calibration Shortcut

Start static reﬂex scan for all en-

abled cameras

Inertial Sensor Calibration

Room F5

Room adjustment Shift + F5

Body F6

Body adjustment Shift + F6

Fingertracking

Measurement Tool

Table 4.16: Menu Calibration

Start static reﬂex scan for all enabled cameras All ART cameras are able to sup-

press all reﬂexes in certain areas of the image sensor. This is especially important for

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4 System setup

setups in multisided projections: these cameras are mounted in the corners of the multi-

sided projection and usually get a lot of unwanted reﬂexes from the nearby walls. To gain

good tracking results, these reﬂexes should be suppressed. The feature can be enabled

or disabled either globally for all cameras or individually for each camera in the camera

settings. Scanning for static reﬂexes allows searching the measurement volume for un-

wanted reﬂexes. Areas are deﬁned around the visible reﬂexes, where all reﬂexes should

be suppressed later during measurements.

ZBe sure to remove all targets from the measurement volume before

starting the scan.

Inertial Sensor Calibration This function carries out a drift correction for all inertial

sensors. Please refer to chapter 4.4 on page 63 for more information.

Room Use the room calibration menu to conﬁgure your room calibration set concerning

wand length and marker distances. The wand length is printed on a label on the wand -

please enter the value here.

Figure 4.48: A room calibration set consisting of angle and wand

Marker distances deﬁnes the type of room calibration set - it can either be Room Cali-

bration Set TP,Room Calibration Set 410 or Room Calibration Set 710. When choosing

expert the angle of the room calibration set may be deﬁned by the user. Then, the dis-

tances between the markers on the angle have to be conﬁgured.

Deﬁne the coordinate system as ’normal’ or ’powerwall’. The layout of the coordinate

system is shown in the 4.49 on page 113. You may adjust the ’duration’ of the room

calibration (→Show details) in a range of 10s - 100s. Resetting the value to default is

achieved by pressing the Set to default button (default = 30s).

Changing the duration of the room calibration, especially towards

shorter durations, may lead to bad room calibration results! Please

make sure that you are always able to cover two thirds of the tracking

volume within the set time.

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(a) ’normal’ (b) ’powerwall’

Figure 4.49: Deﬁning the coordinate system for the room calibration

If you are re-calibrating your room use the checkbox re-calibration in the bottom left cor-

ner to indicate it to the tracking system. For more information about room re-calibration

please refer to page 82.

Please refer to chapter 4.5.2 on page 77 for the details on how to perform a room calibra-

tion.

Room adjustment During a room calibration origin and orientation of the room coordi-

nate system are located by the position of the calibration angle; e.g. the reﬂective marker

in the angle’s vertex (marker #1) deﬁnes the origin of the coordinate system. Oftentimes

it might be more suitable to set the coordinate system in respect to well-known points in

space.

Possible scenarios for the application of the Room adjustment functionality are:

•adjust the origin to the center of a screen

•align the coordinate system colinear / parallel to a screen (even very small angular

deviations might lead to substantial misalignment over the full width of the projection

0.1◦on 5m length equals 8.7 mm deviation)

•shift and / or rotate the camera coordinate system to match a reference coordinate

system, e.g. from CAD models

•maintaining a speciﬁc coordinate system / orientation when using mobile installa-

tions of cameras, i.e. frequently changing the camera setup locations (suitable ref-

erence points provided)

In all these cases the coordinate system must be altered after calibration.

If you press Enter or click OK , all changes which have been done so far

will be conﬁrmed (changes are sent to the controller) and the dialogue

closes. Pressing Apply accepts the current changes, but the dialogue

is left open. Discard all changes by pressing Cancel.

Coarse The Coarse tab offers a simple way to manipulate the orientation of the room

coordinate system with just one click (see ﬁgure 4.50 on page 114. You can deﬁne the

orientation of two axes using the drop-down menus - the third one will be oriented auto-

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4 System setup

matically according to the right-hand rule. Press Reset to switch back to the unmodiﬁed

state.

Figure 4.50: Room adjustment dialogue (coarse)

Fine More detailed options to adjust the room coordinate system are given in the Fine

tab (see ﬁgure 4.51 on page 115). By default a cartesian coordinate system is displayed

on the left side of the window. The room coordinate system is shown as a triplet of arrows

with a deﬁned color-coding (x-axis: red, y-axis: green, z-axis: blue), while the xy-plane is

shown as a yellow grid. The current and the transformed room coordinate systems are

marked with (’O’) and (’T’) respectively.

The View position and View orientation may be moved along and / or rotated around all

axes in two different ways:

1. hold down the "Ctrl" key and the left / right mouse button to change the position /

orientation

2. hold down the "Ctrl" key and use the mouse wheel to zoom

3. use the six control dials (below the graphical view) to adjust position and orientation

To center the current room coordinate system, press ’Adjust view’. To restore the default

view (shift and orientation), press ’Reset view’. The visualisation itself can be changed

by clicking the right mouse button to open a menu with the following options. (De-)select

the appropriate ones by (un-)ticking.

Option Description

’Long axes’ extends the coordinate axes of the body coordinate system by

inﬁnite dashed lines

’Show XY plane’ shows the XY plane (yellow grid)

’Show YZ plane’ shows the YZ plane (cyan grid)

’Show XZ plane’ shows the XZ plane (magenta grid)

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Figure 4.51: Room adjustment dialogue (ﬁne)

On the right side of the window the room coordinate system may be customized freely,

i.e. user-speciﬁc.

Action Description

Zero point offset [mm] translate the room coordinate system along its axes in steps of 1mm

Reset vector reset the zero point offset to the unmodiﬁed state (0.00 mm)

Rotation angles [deg] rotate the room coordinate system around its axes (from -180 to +180

◦)

Reset angles reset the rotation angles to the unmodiﬁed state (0.00 ◦)

Scaling factor enlarge / shrink the room coordinate system uniformly up to a factor of

+/-5 percent

Reset scaling reset the scaling factor to the unmodiﬁed state (1.0000)

Matching start up a module for transforming and matching to a reference coordi-

nate system (Measurement Tool & license provided)

All entered transformation values are given in the original room coordinate system.

Example: let’s assume a standard room coordinate system (xy plane on the ground, z

axis facing upwards) that was calibrated using a “Room Calibration Set” RCS 410. So the

current origin is located 43 mm above the ground (refer to chapter 4.5.2 on page 77 about

details). If the new desired origin should be placed 1 m above the ground, then the Zero

point offset for z must be 957 mm (1000 mm - 43 mm).

Transform Press Matching in the Fine tab to open the room matching dialogue (see

ﬁgure 4.52 on page 117). This functionality depends on the Measurement Tool license.

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4 System setup

iIf the Measurement Tool is not tracked (calibration provided) matching

cannot be performed. Use an authorised Measurement Tool by ART for

best results.

ZDeselect any previously assigned Measurement Tool References prior

to matching of the coordinate systems. Otherwise matching results

will be erroneous.

The purpose of the coordinate transformation is to convert the origin and orientation of the

initial camera coordinate system (indicated with ’O’) into a reference coordinate system

(indicated with ’T’), e.g. given by a certain object or CAD model. All measurement data

will be transformed with respect to the reference coordinate system (’T’). To this end a

three-step calibration procedure has to be performed:

1. Add measurement data from the reference coordinate system (’T’) by manually en-

tering the coordinates into the table reference points using the button Add. A mini-

mum of three (3) data points is necessary for calculations. Delete single data points

by selecting the corresponding row and press Remove. Alternatively load the coor-

dinates from a text ﬁle (ASCII) using the button Load. The text ﬁle must comply to

the following format:

1 1.00 20.00 300.00 <CRLF>

2 4.00 50.00 600.00 <CRLF>

3 7.00 80.00 900.00 <CRLF>

# x y z <CRLF>

The import strictly follows the sequence from the ASCII text ﬁle. The current set of

reference points can be saved by pressing Save.

2. Select a calibrated and tracked Measurement Tool from the drop-down menu and

measure all points (e.g. on the corresponding object) which directly relate to the

reference points (e.g. from a CAD model) deﬁned in step 1.

Each measurement can be started by:

•clicking the button Measure

•clicking the start button on the Measurement Tool (if applicable)

•using the “measurement start simulation” of the Measurement Tool (refer to 5.4

on page 144)

•clicking a button of an assigned Flystick

The following calculations try to correct the order of the measured points, if they

don’t correspond to the order of the reference points. Sometimes this does not

produce the correct result, especially if the points are located too symmetrically

toward each other. In this case toggle the tickbox preserve order of points to lock

the order between reference points and measured points.

ZFor proper matching it is essential to ensure the correct correspon-

dence between reference points and measured points.

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3. After having measured all corresponding points the calculation is started automati-

cally and the result of the transformation is displayed in the textbox transformation.

Double-check that all measured data points correspond to the correct reference data

points. Delete single data points by selecting the corresponding row and press Re-

move or delete all data points to start all over by pressing Clear . The residual error

(standard deviation) is a measure of the transformation quality, i.e. how well the

measured data ﬁt the corresponding reference points. It can be inﬂuenced mostly

by the quality of data acquisition and by differences in scale of the camera and refer-

ence coordinate systems. Pressing OK accepts this transformation and closes the

dialogue box.

Figure 4.52: Room matching dialogue

The calculated transformation is applied on both zero point offset as well as rotation

angles in Fine tab. Do not further manipulate the values manually. Press Enter or click OK

to conﬁrm the resulting transformation and to close the dialogue. Pressing Apply accepts

the current changes and leaves the dialogue open. Discard all changes by pressing

Cancel.

Body Select the body you want to calibrate and tick the checkbox if you want to perform

a re-calibration. Deﬁne the type and the coordinate system which should be used for the

calibration.

If you want to use body calibration ﬁles for calibrating your target, just click Load ﬁle(s)

and select the appropriate calibration ﬁle(s). By clicking on Save ﬁle(s) you can save your

body calibrations in separate text ﬁles.

Please refer to chapter 4.5.3 on page 84 for the details on how to perform a body calibra-

tion.

Body adjustment Use this menu (see ﬁgure 4.43 on 90) to visualise and manipulate

calibration data of rigid bodies. Just select the desired body from the drop-down list at the

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4 System setup

top of the window. By default a cartesian coordinate system is displayed on the left side

of the window depicting the selected rigid body’s geometry (’Graphic view’).

The body coordinate system is shown as a triplet of arrows with a deﬁned color-coding

(x-axis: red, y-axis: green, z-axis: blue), while the xy-plane is shown as a yellow grid. All

markers, however, are visualised by sequentially colored spheres (RGB) for better iden-

tiﬁcation. In case the selected rigid body features visibility restrictions, emission cones

may have been predeﬁned. Direction of visibility (emission vector) is depicted as an ar-

row (white) for each marker, while the angular restriction (emission aperture) is shown as

a cone (grey).

The View position and View orientation may be moved along and/or rotated around all

axes in two different ways:

1. hold down the "Ctrl" key and the left / right mouse button to change the position /

orientation

2. hold down the "Ctrl" key and use the mouse wheel to zoom

3. use the six control dials (below ’Graphic view’) to adjust position and orientation

To restore the default view, just press ’Reset view’. Tick the ’use tracked orientation’

checkbox to switch to online mode (i.e. the 3D-representation of the target in the ’Graphic

view’ is depicting movements / rotation of the target in the "real world").

The visualisation can be changed by clicking the right mouse button to open a menu with

the following options. (De-)select the appropriate ones by (un-)ticking.

Option Description

’Small markers’ reduces the size of the markers

’Colored markers’ shows the markers in different colors (untick: greyish)

’Emissions’ shows predeﬁned direction (arrows) and angular restriction

(cones) of visibility (if applicable)

’Long axes’ extends the coordinate axes of the body coordinate system by

inﬁnite dashed lines

’Show COG’ shows the body’s center of gravity (white square)

’Show XY plane’ shows the XY plane (yellow grid)

’Show YZ plane’ shows the YZ plane (cyan grid)

’Show XZ plane’ shows the XZ plane (magenta grid)

’Show room orientation’ shows the room coordinate system (only available when check-

box ’use tracked orientation’ is ticked)

’Add line between markers’ adds a line between two selected markers (option greyed out until

two markers are selected)

’Delete line between markers’ removes a line between two selected markers (option greyed out

until line is selected)

’Data view’ switches to the data view

For manipulating the body geometry you have the choice between general or special

options:

General The body coordinate system may be customized freely, i.e. user-speciﬁc.

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Action Description

Body position [mm] translate the body coordinate system along its axes in steps of 1mm

Body orientation [deg] rotate the body coordinate system around its axes

Set origin activate a marker in the ’Graphic view’ by left-clicking with the mouse.

The marker is highlighted and the button Set origin is activated. Press-

ing this button translates the origin of the body coordinate system into

the center of the selected marker.

Set origin to COG translate the origin of the body coordinate system into the target’s center

of gravity

Set axis activate two markers sequentially in the ’Graphic view’ by left-clicking

with the mouse. The ﬁrst one is highlighted in white, the second one in

grey. Additionally, the button Set axis is activated. Pressing this button

opens a dialogue to conﬁgure the transformation.

Adjust axes to room pressing this button aligns the body coordinate system collinear to the

room coordinate system

Delete marker activate a marker in the ’Graphic view’ by left-clicking with the mouse.

The marker is highlighted and the button Delete marker is activated.

Pressing this button removes the selected marker from the target ge-

ometry.

Special Choose from the following predeﬁned transformations:

•due to body

The body coordinate system is completely deﬁned by the target geometry (see page

86).

•due to room (origin in COG)

The coordinate system is rotated and aligned collinear to the room coordinate sys-

tem with the origin set in the center of gravity (COG) (see page 86). In order to use

this function, the checkbox ’use tracked orientation’ has to be ticked.

•due to room (origin in marker)

The coordinate system is rotated and aligned collinear to the room coordinate sys-

tem with the origin set in one speciﬁc marker (see page 86). In order to use this

function, the checkbox ’use tracked orientation’ has to be ticked.

iPredeﬁned visibility restrictions (emission vectors and angles of aper-

ture) are retained along all body transformations.

If you press Enter or click OK , all changes which have been done for

all bodies will be conﬁrmed (changes are sent to the controller) and

the dialogue closes.

Pressing Apply only results in changes of the currently selected body

- the body will be redrawn afterwards.

If the MultiUser function for Flysticks is enabled the Body Adjustment

module will only load standard bodies. If you want to adjust the body

calibration data of your Flystick, please make sure that the MultiUser

function is disabled (Settings →Flystick) - a label ’MultiUser function

should be disabled!’ will appear at the bottom of the dialogue.

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4 System setup

Hybrid Body This function performs a hand-eye calibration to combine an inertial sen-

sor with its corresponding optical target. Please refer to chapter 4.4 on page 66 for more

information.

Fingertracking Deﬁne a new or select an existing ’hand geometry name’. Conﬁgure

handedness as being ’left’ or ’right’. Select the type of ﬁngerset.

When clicking on the button Help a pop-up window appears where the calibration process

is explained and visualized.

Please refer to chapter 5.3 on page 142 for more information.

Measurement Tool Perform a tip calibration for the Measurement Tool that is currently

inside the tracking volume. DTrack2 automatically detects the ID of the Measurement

Tool and assigns the tip calibration. Just press Calibrate to start the calibration process.

During calibration please move the Measurement Tool while keeping the tip still at exactly

one position.

ZNote that the progress bar is not continuing if the pointing device is

not moved sufﬁciently.

Please refer to chapter 5.4 on page 145 for more information.

4.5.6.5 Menu Display

Display Shortcut

Monitor 2DOF

Data F10

Fingertracking

Flystick

Measurement Tool

Events

Set to default

Table 4.17: Menu Display

Monitor 2DOF The Monitor 2DOF display essentially is a graphical display of the ﬁeld

of view of the IR cameras and of the markers that are seen by the cameras. The Monitor

2DOF display shows a black window for each IR camera (equivalent to the ﬁeld of view),

with a schematic display of positions and sizes of all recognized markers.

In case, several ARTTRACK cameras are being used in one system, it will be helpful

that the number of cameras shown in the Monitor 2DOF display can be adjusted. From

DTrack2 v2.8.1 you may use the slider ’cameras per tab’ in order to achieve clear ar-

rangement. Tabs containing the remaining cameras will be added to the Monitor 2DOF

display.

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The special tab ’most active cameras’ contains these cameras which see the markers of

the targets most of the time.

Example: consider a four camera system with camera01 thru camera04 and you have

set the number of ’cameras per tab’ to two. Now, if you move a target in front of camera02

and camera03 most of the time, these two cameras will then be shown in the ’most active

cameras’ tab.

A simple color code signiﬁes the size and the circularity of the markers (green = very

good quality, yellow = good quality, red = poor quality). Each marker is either displayed

as a circle or as a cross. This indicates the projected size of the marker on the CCD chip

inside the camera (i.e. circle = big marker and cross = small marker).

As a rule of thumb: for measurement applications with high accuracy requirements the

markers should be displayed in green; for VR applications yellow markers are sufﬁcient.

The Monitor 2DOF display is particularly useful for the ﬁnal adjustment (especially for ori-

entation adjustments) of the IR cameras.

If current room calibration information does not contain some of the currently connected

cameras, on their corresponding monitors a red text “(re-)calibration required!” appears.

On the other hand, if the room calibration does not have some cameras which were

present when calibrating the room, corresponding camera monitors are disabled (crossed

out).

In the Monitor 2DOF display it is possible to interact with your mouse as certain functions

are assigned to the mouse buttons.

•left mouse button:

Click and hold down to move a camera display within the Monitor 2DOF view.

•middle mouse button:

Click to hide all camera displays except for the one you pointed at. Click once again

and all camera displays are shown.

•right mouse button:

A menu is opened; see table 4.18 for more details.

Data On the left hand side, the Data display shows the 6DOF measurement results of

the position and orientation of the body relative to the room coordinate system. The rota-

tion angles are rotations around the X, Y and Z axis. The mathematical deﬁnition can be

found in chapter B on page 203. A simple colour code indicates if the body is tracked or

not:

green ... body is being tracked; tracking data is displayed

yellow ... body is being tracked only by the means of the intertial sensor

(only rotational data!)

red ... body is not being tracked; instead of tracking data dashes are

displayed

white ... body is not calibrated; columns are left blank

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4 System setup

Function Shortcut

Grid G Shows a grid in the camera display.

Cross C Shows a cross in the camera display.

Fullscreen F Resizes Monitor 2DOF view to full

screen and back.

One Camera Only show the view of the selected

camera.

Display upside down Changes display orientation. ’UD’ is

displayed in the camera display.

Display blinking ARTTRACK5 only : Activates / deacti-

vates blinking of 2-digit LED matrix and

status LEDs for easy identiﬁcation of

camera.

Static Reﬂex Suppression

Active Enable static suppression of reﬂexes.

’SR’ is displayed in the camera display.

Start scan for all enabled cameras Initiates a scan for static reﬂexes. En-

abled only if Active is ticked.

Edit reﬂex suppression areas E Enter the reﬂex suppression area edit

mode in order to interactively suppress

unwanted reﬂexes.

Table 4.18: Features of the Monitor 2DOF view

On the right hand side, the 3DOF calculation for single markers or uncalibrated targets

is shown. All recognized single markers that are have not been assigned to a calibrated

6DOF body are shown here.

Note that the calculation of 3DOF markers has to be activated in Settings →Tracking by

ticking the checkbox. Otherwise, the positions will not be calculated.

Additional information for inertial sensors In the Data Display additional information is pro-

vided for the inertial sensor:

•sensor ID

•battery level

•temperature in ◦C

The temperature values between single inertial sensors may vary. The

operating temperature is reached as soon as there are no more tem-

perature changes inside the sensors indicated by a green status bar. It

is not dependent on the absolute temperature value.

Fingertracking The Fingertracking display shows the measurement results of the hands

- i.e. of each ﬁnger (thumb, index, middle, ...) - that are available in the measurement vol-

ume. A simple colour code shows the status of the Fingertracking:

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green ... Fingertracking device is being trac