Sensory feedback system using interferential current for EMG prosthetic hand

The purpose of this study was to develop a new type of sensory feedback system for myoelectrically controlled biomimetic prosthetic hand. One of the characteristic features of the neuromuscular control system in man is the increase in the compliance around the joint with decreasing activity of the muscle. For the sensory feedback system we used interferential current that use two waves and interfere to synthesize a low frequency in the body. One frequency was fixed at 5000 Hz and the other frequency was changed from 2000 Hz; to 4900 Hz. As the result stimulus frequency in the body was changed from 100 Hz to 3000 Hz. By the experiments we measured that the subjects could distinguish the change of stimulus frequency and confirmed that the interference current is useful method for sensory feedback system of a prosthetic hand. As a future task, we will try to produce a sensory feedback device for a prosthetic hand, using the interference current.