Modified a computer mouse so that its left button is operated by the electromyographic (EMG) signal. This signal is produced when the EMG electrodes are connected on the left forearm, so that left-clicks would be produced by closing the hand. To verify and test this system video game, Flappy Bird, was used to test the output.
Block Diagram
Three electrode leads are connected from the forearm muscles to an instrumentation amplifier incorporating a circuit for common-mode rejection.
The signal will then be band-pass filtered in accordance with the EMG signal bandwidth. Since the EMG signal is not rhythmic in nature, typical signal processing usually consists in rectification and integration.
A comparator with hysteresis will then compare the integrator output to a threshold before triggering a monostable circuit that will send a pulse through an optoisolator to a relay that will activate the mouse left button while playing a game of Flappy Bird.
What You'll Need
Six AA Batteries
Four of these batteries generate (+3V -3V) required by all the circuits
The remaining two batteries supply +5V to the Mouse
A Mouse
A Relay
An Optoisolator (Transfers electric signals from the body to the system, ensuring user safety through isolation)
An Instrumentation Amplifier (This setup uses the AD620A Instrumentation Amplifier and an OP97 Operational Amplifier)
A Band-Pass Filter (Used for EMG Signal Filtering/Envelope Detection)
A Rectifier/Integrator (Given that EMG signals lack rhythm, rectification and integration are essential)
A Comparator (A circuit that activates when the forearm's muscle intensity hits the set threshold)
A Monostable (Transforms the comparator signal into well-defined pulses or discrete values)
