Direct and Inverse Modeling in EMG

Abstract

Muscle activity is accompanied by an electrical signal (electromyogram or EMG) which travels through a complex volume conductor before reaching the surface of the body. Most usually, this signal is recorded with surface electrodes since it is not invasive but due to its alterations induced by the volume conductor, information on the signal origin is difficult to obtain. In such a context, the use of a direct and inverse model could offer useful information to help analyze and take benefits of surface EMG signals. We are developing such a model in the context of improving the control of myoelectric prostheses capable of producing various movements This could be possible by exploiting the presence of anatomical compartments within large muscles such as the biceps and triceps brachii. If activation of those compartments could be individually activated, they could be used to activate modern myoelectric prostheses. To develop the models, a tank circled with recording electrodes and dipoles positioned at known positions was used. Preliminary results are presented here.


Index Terms—Electromyography, direct and inverse model, Poisson equation, myoelectric prosthesis.