Surface EEG and Myoelectric Prosthesis Control

Abstract

An electromyogram (EMG) signal is the signature of a muscle contraction by which our limbs can be moved. When part of a limb is lost, muscles used to move it can still be contracted. An amputee person can then used those muscular signals to activate a myoelectric prosthesis and produce some movements again. Newest myoelectric prostheses are capable of many degrees of freedom (DOF) and therefore many signals are required to fully benefit from their capabilities. In search of many muscle control sites to operate such prosthesis, muscle compartments, which are intra-muscular subdivisions innervated by individual muscle nerve branch, can be exploited. In order to explore if the compartments of those muscles could be voluntary controlled, we placed an array of 7 pairs of equally spaced surface electrodes across the biceps brachii (BB) of healthy subjects. EMG signals where collected while subject’s hand was in different positions. Our preliminary results indicate that depending on hand positions, parts of the biceps muscle are more active than others. Such knowledge could be useful for the control of a modern myoelectric prosthesis.

Index Terms— Biceps brachii; Compartment; Electrode array; Surface EMG