Purpose

1
Purpose

• Design a system that will efficiently measure
  signals produced by muscle movement and use these
  signals to operate a remote control car.

2
Current Applications

• EMG applications has two key categories
• Biofeedback
• Communication

3
Current Applications

• Biofeedback
• Mainly for clinical purposes
• Utilized as muscle relaxation and treatment
• Also to prevent painful muscle conditions
• Communication
• Mostly experimental
• Muscle movements that control electronic and
  computer devices

4
Current Products

• Prices ranges from 175 - 2000
• Inexpensive
• Have no computer interface
• Generally only Useful for muscle training

5
Electric Activity?

• The contractions of all muscles are triggered by
  electrical impulses called Motor Unit Action
  Potentials (MUAPs).
• MUAPs can be created internally or externally by
  devices such as the pacemaker.

6
Electromyography

• Recording of Motor Unit Action Potentials (MUAPs)
  produced by muscle movement
• Frequency Range
• 50 500 Hz
• Voltage Range
• 0.75 2000 uV

7
Electromyography

• Underlying Processes
• Amplification
• Signal-to-Noise Ratio
• Common Mode Rejection Ratio
• Filtering
• Sampling

8
Potential Applications

• Wheelchair Control
• Control the motions of a wheelchair without using
  the hands
• Signals go directly from face to wheelchair
  interface
• On-screen Mouse Control
• Move mouse pointer using facial muscles alone

9
Interface to PC

• Digitize Signals Measured with EMG
• Analog to Digital Converter
• Comparator
• Assign Codes for System Control
• Determine Number and Degree of Muscle Movements
  to Execute Commands
• Apply Commands on Test System