On optimal electrode configuration to estimate hand movements from forearm surface electromyography.

Understanding the movement of the hand from sEMG signals acquired on the forearm is key in the development of future prosthetics of the upper limb. Despite the technical advancement on this technique, state of the art of sEMG still relies strongly on optimal electrode placement which is typically performed by a specialist by mean of a heuristic search. Involving a specialist has few major disadvantages including high costs and relatively long schedules. This work searches an optimal electrode configuration which could reduce or avoid the intervention of a specialist. More than 200 different possible electrode configurations were assessed by means of the average recognition rate over 11 different movements of the hand, wrist, and fingers. It is shown that using two rows of 8 equally spaced electrodes around the circumference of the forearm could be an optimal trade-off solution to accomplish the task of recognizing hand movement (ARR = 92%) without the need for a specialist or very complex hardware.