A highly usable and customizable sEMG sensor for prosthetic limb control using polypyrrole-coated nonwoven fabric sheet

A novel sEMG (surface electromyography) sensor using polypyrrole-coated nonwoven fabric sheet as electrodes (PPy-electrode) is proposed for the disabled to control prosthetic limbs in daily life. The PPy-electrodes are sewed on an elastic band to guarantee closely contact to the skin thus to enable stable sEMG measurement with high signal-to-noise ratio. Furthermore, the sensor is highly customizable to fit for the size and the shape of the stump so that the disabled can wear the sensor by themselves. The performance of the proposed sensor is investigated by comparing with Ag/AgCl electrodes with electrolytic gel in an experiment to measure the sEMG from the same muscle fibers. The high correlation coefficient (0.84) between the sEMG measured by the two types of sensors suggests the effectiveness of the proposed sensor. The experiment of sEMG patter recognition to control myoelectric prosthetic hands showed that the PPy-electrodes are as effective as Ag/AgCl electrodes to measure sEMG signals for practical myoelectric control.