Presentation Myoware User Manual AT 04 001

User Manual: Pdf

Open the PDF directly: View PDF PDF.
Page Count: 8

DownloadPresentation Myoware User Manual AT-04-001
Open PDF In BrowserView PDF
© 2015

3-lead Muscle / Electromyography
Sensor for Microcontroller Applications
MyoWare™ Muscle Sensor (AT-04-001)

DATASHEET

FEATURES
 NEW - Wearable Design
 NEW - Single Supply
 +2.9V to +5.7V
 Polarity reversal protection
 NEW - Two Output Modes
 EMG Envelope
 Raw EMG
 NEW - Expandable via Shields
 NEW - LED Indicators
 Specially Designed For Microcontrollers
 Adjustable Gain
APPLICATIONS
 Video games
 Robotics
 Medical Devices
 Wearable/Mobile Electronics
 Prosthetics/Orthotics

What is electromyography?
Measuring muscle activation via electric potential, referred to as electromyography (EMG), has
traditionally been used for medical research and diagnosis of neuromuscular disorders. However,
with the advent of ever shrinking yet more powerful microcontrollers and integrated circuits, EMG
circuits and sensors have found their way into prosthetics, robotics and other control systems.

Sensor Layout

Mid Muscle Electrode Snap
Power Switch

Raw EMG Signal - 7
Shield Power (output) - 8
GND - 9

1 - Power Supply, +Vs
2 - Power Supply, GND
3 - Output Signal, SIG

Adjustable Gain
End Muscle Electrode Snap

Reference Electrode Cable
EMAIL: support@advancer.co

4 - Mid Muscle Electrode Pin
5 - End Muscle Electrode Pin
6 - Reference Electrode Pin
www.AdvancerTechnologies.com

© 2015

Setup Configurations (Arduino is shown but MyoWare is compatible with most development boards)

RECOMMENDED

a) Battery powered with isolation via no direct external connections
Note: Since no component is
connected to electrical grid,
further isolation is not
required. It is also
acceptable to power the
MCU with a battery via the
USB or barrel ports.

Note: Isolation amplifier and
battery provide isolation
between user and electrical
grid. IC models are
suggestions only.

Isolation
Amplifier
(ISO124)

EMAIL: support@advancer.co

(Note: Arduino and batteries not included. Arduino setup is only
an example; sensor will work with numerous other devices.)

b) Battery powered sensor, Grid powered MCU with output isolation

www.AdvancerTechnologies.com

© 2015

Setup Configurations (cont’d)
c) Grid powered with power and output isolation

Note: Isolation amplifier and
power isolator provide
isolation between user and
electrical grid. IC models are
suggestions only.

Power Isolator
(R1SE-0505-R)

Isolation
Amplifier
(ISO124)

d) Grid powered. Warning: No isolation.

Note: This configuration has no
isolation. Usually safe but rare
situations could create a
current loop to the electrical
grid. Not suitable for
commercial applications.

EMAIL: support@advancer.co

www.AdvancerTechnologies.com

© 2015

Setup Instructions

Note: Not To Scale

Example Sensor Location for Bicep
1)
2)

Thoroughly clean the intended area with soap to remove dirt and oil
Snap electrodes to the sensor’s snap connectors
(Note: While you can snap the sensor to the electrodes after they’ve been placed on the muscle, we do not
recommend doing so due to the possibility of excessive force being applied and bruising the skin.)

3)

4)

Place the sensor on the desired muscle
a. After determining which muscle group you want to target (e.g. bicep, forearm,
calf), clean the skin thoroughly
b. Place the sensor so one of the connected electrodes is in the middle of the
muscle body. The other electrode should line up in the direction of the muscle
length
c. Peel off the backs of the electrodes to expose the adhesive and apply them to
the skin
d. Place the reference electrode on a bony or nonadjacent muscular part of your
body near the targeted muscle
Connect to a development board (e.g. Arduino, RaspberryPi), microcontroller, or ADC
a. See configurations previously shown

EMAIL: support@advancer.co

www.AdvancerTechnologies.com

© 2015

Why is electrode placement important?
Raw EMG output

Innervation Zone

Correct Placement
Midline of the muscle belly
between an innervation zone
and a myotendon junction

Midline Offset

Myotendon Junction

Position and orientation of the muscle sensor electrodes has a vast effect on the strength of
the signal. The electrodes should be place in the middle of the muscle body and should be
aligned with the orientation of the muscle fibers. Placing the sensor in other locations will
reduce the strength and quality of the sensor’s signal due to a reduction of the number of
motor units measured and interference attributed to crosstalk.

EMAIL: support@advancer.co

www.AdvancerTechnologies.com

© 2015

RAW EMG vs EMG Envelope
Our Muscle Sensors are designed to be used directly with a microcontroller. Therefore, our
sensors primary output is not a RAW EMG signal but rather an amplified, rectified, and
integrated signal (AKA the EMG’s envelope) that will work well with a microcontroller’s
analog-to-digital converter (ADC). This difference is illustrated below using a
representative EMG signal. Note: Actual sensor output not shown.

RAW EMG Signal

Rectified EMG Signal

Rectified & Integrated
EMG Signal

Reconfigure for Raw EMG Output
This new version has the ability to output an amplified raw EMG signal.
To output the raw EMG signal, simply connect the raw EMG signal pin to your measuring
device instead of the SIG pin.
Note: This output is centered about an offset
voltage of +Vs/2, see above. It is important
to ensure +Vs is the max voltage of the
MCU’s analog to digital converter. This will
assure that you completely see both positive
and negative portions of the waveform.

EMAIL: support@advancer.co

Connect

www.AdvancerTechnologies.com

© 2015

This new version has embedded electrode
snaps right on the sensor board itself,
replacing the need for a cable. However, if
the on board snaps do not fit a user’s
specific application, an external cable can
be connected to the board through three
through hole pads shown above.

Ref
End
Middle

Connecting external electrode cables

Middle
Connect this pad to the cable leading to an
electrode placed in the middle of the muscle body.
End
Connect this to the cable leading to an electrode
placed adjacent to the middle electrode towards
the end of the muscle body.
Ref
Connect this to the reference electrode. The
reference electrode should be placed on an
separate section of the body, such as the bony
portion of the elbow or a nonadjacent muscle

Adjusting the gain
We recommend for users to get their sensor setup working reliably prior to adjusting the
gain. The default gain setting should be appropriate for most applications.
To adjust the gain, locate the gain potentiometer in the lower left corner of the sensor
(marked as “GAIN”). Using a Phillips screwdriver, turn the potentiometer counterclockwise
to increase the output gain; turn the potentiometer clockwise to reduce the gain.
Note: In order to reduce the required voltage for the
sensor, the redesign switch out a JFET amplifier for a
CMOS amplifier. However CMOS amplifiers tend to have
slower recovery times when saturated. Therefore, we
advise users to adjust the gain such that the output signal
will not saturate the amplifier.

EMAIL: support@advancer.co

www.AdvancerTechnologies.com

© 2015

Electrical Specifications

Parameter

Min

TYP

Max

Supply Voltage

+2.9V

+3.3V or +5V

+5.7V

Adjustable Gain Potentiometer

0.01 Ω

50 kΩ

100 kΩ

Output Signal Voltage
EMG Envelope
Raw EMG (centered about +Vs/2)

0V
0V

---

+Vs
+Vs

Input Impedance

--

110 GΩ

--

Supply Current

--

9 mA

14 mA

Common Mode Rejection Ratio (CMRR)

--

110

--

Input Bias

--

1 pA

--

Dimensions
2.06 (52.3)
1.75 / (44.4)

2 x 0.125” DIA. Thru Hole

0.82
(20.7)

0.51
(13.0)

0.019
(5.0)

1.93 / (49.1)

EMAIL: support@advancer.co

www.AdvancerTechnologies.com



Source Exif Data:
File Type                       : PDF
File Type Extension             : pdf
MIME Type                       : application/pdf
PDF Version                     : 1.5
Linearized                      : No
Page Count                      : 8
Language                        : en-US
Tagged PDF                      : Yes
Title                           : PowerPoint Presentation
Author                          : Brian Kaminski
Create Date                     : 2016:03:17 21:30:52-04:00
Modify Date                     : 2016:03:17 21:30:52-04:00
Producer                        : Microsoft® PowerPoint® 2013
Creator                         : Microsoft® PowerPoint® 2013
EXIF Metadata provided by EXIF.tools

Navigation menu