Bilateral control using functional electrical stimulation

This paper describes bilateral control using functional electrical stimulation (FES). Bilateral control is a teleoperation system using force feedback. If we can use it in everyday life, it could allow remote diagnosis by doctors and communication of tactile information. However, in conventional studies of bilateral control, operators must wear robot arms. Using them in everyday life is not desirable, because they are restrained and make human feel uncomfortable. Therefor, we propose the use of FES in the transmission of force information. An experiment on bilateral control of elbow joints with five healthy male participants was conducted. Biceps brachii muscles and triceps brachii muscles were stimulated using adhesive electrical pads. Position symmetrical bilateral control was implemented so that the deviation of the position of each other is 0. The angles of the elbows were measured by encoders, and a proportional-integral-derivative (PID) controller was implemented as a position controller. The experimental results show that the proposed method showed good performance in the practical viewpoint. However, the elbows of some subjects could not be successfully controlled because interference current occurred between their muscles.