Study on a switching system of operation mode for upper-limb prosthesis bearing flexibility like a human elbow

Abstract

In this study, we propose an EMG control system including switching system of action mode using EMG (electromyogram) signal by the elevation of scapula for upper-limb prosthesis. This EMG control system operates elbow, wrist and hand of upper-limb prosthesis, using surface EMG signal of the biceps brachii and the triceps brachii. The switched these three action modes are controlled by surface EMG signals of the elevation of scapula. The main muscle working in the elevation of scapula is the trapezius. Some practical myoelectric prostheses use EMG of human arm's contraction as switching plural actions. However, this study proposed by the elevation of scapula instead of arm's contraction. As a reason for that the proposed upper-limb prosthesis uses EMG signal of arm's contraction-relaxation action as input signal, for realization of flexibly elbow's action in the prosthesis. The proposed EMG control system including a simple upper-limb prosthesis was manufactured using Arduino microcomputer. As results of the test operation, it confirmed that the working of three actions are switched in sequence by the elevation of scapula.