Sliding Mode Control of an Actuated Knee Joint Orthosis

Abstract

In this paper, a robust sliding mode controller is developed to control an orthosis used for rehabilitation of lower limb. The orthosis is defined as a mechanical device intended to physically assist a human subject for the realization of his movements. It should be adapted to the human morphology, interacting in harmony with its movements, and providing the necessary efforts along the limbs to which it is attached. The application of the sliding mode control to the Shank-orthosis system shows satisfactory dynamic response and tracking performances. In fact, position tracking and speed tracking errors are very small. The sliding mode controller effectively absorbs disturbance and parametric variations, hence the efficiency and robustness of our applied control.