Design of EMG based Control System for Prosthetic Arm

Abstract

Prosthesis, field of bio-mechatronics, is an artificial extension used to replace the function or appearance of a missing limb or lost body part due to injury (traumatic), to correct congenital deficiencies or to supplement defective body parts. A myoelectrically controlled prosthesis detects muscle contractions using electrodes and this electrical activity acts as a signal to activate the prosthesis. In the presented work, the EMG signal is acquired using surface electrodes placed on the muscles. The acquired signal is then processed using Signal Conditioning Unit in order to amplify, filter and buffer. The EMG signal is very noisy and the noise components are of high frequency (more than 200 Hz of few mv). A low pass, 2nd order Butterworth filter of 100 Hz is used to extract the EMG signal from the human muscle. The filtered output is buffered using the unit gain operational amplifier configuration. The final output signal is converted to a digital signal using 16-bit serial ADC. Once the EMG signal is available in digital form, the same can be utilized to control the robotic arm or in any application