Sliding mode control of a finger for a prosthetic hand

Abstract

A prosthetic finger model, intended to imitate a real human hand and for use in replacing the real index finger of an amputee, is designed using tendons instead of joint motors. A dynamic model of the prosthetic finger model is developed, and a non-chattering robust sliding mode control is applied to make the model follow a certain trajectory. Trajectory planning of the finger model is based on images of the closing motion of a human hand, and time varying reference joint angles are obtained using these images. The robustness of the controller is confirmed by introducing an unexpected sudden joint friction induced in the prosthetic finger.