Myoelectric signal based lower arm prosthesis

Abstract

This study is mainly on the control of the stepper motor by using the electromyographic (EMG) signals. When a muscle is contracted, a feeble electric potential is produced. Surface electrodes can sense this muscle activity potential when placed over the muscle. The signal detected by the electrodes is amplified, processed, and then used as input to the Basic Stamp Micro Controller. This Basic Stamp is a type of microcontroller which gives an output to the stepper motor driver in accordance to the processed EMG input signals. Then the driver will give an output to control the stepper motor. This stepper motor will be acting as aluminum mechanical limb The Electromyographic signal is a very small signal and because of that, amplifying this signal is important before we could process it. This signal will be separated into two range values to control the motor in two directions, clockwise and counter clockwise. When we raise the hand, the muscle will produce EMG signal with certain magnitude and then the mechanical arm raises (clockwise direction of the stepper motor) just like our hand. After that, when we lower the hand and the muscle will produce EMG signal with certain magnitude and the mechanical arm also follows (counter clockwise direction of the stepper motor.). The project also presents some experimental details in terms of controlling the stepper motor using the Basic Stamp Microcontroller.