T-S Tracking Controller Design for Sys-Reeduc: a Descriptor Approach

This paper deals with the tracking trajectory control law of Sys-Reeduc, a closed muscular chain lower limbs rehabilitation device. Following a previously proposed generic control structure, the human efforts applied to this device is considered as an external disturbance to the system's dynamics. The dynamical model of the rehabilitation device is written as a Takagi-Sugeno descriptor. A non-PDC controller (Parallel-Distributed-Compensation) is synthesized to ensure the tracking trajectory with external disturbances attenuation. Stability conditions are given in terms of Linear Matrix Inequalities (LMI) using a fuzzy Lyapunov function. Finally, simulation results of the new rehabilitation device with isokinetic movement illustrate the efficiency of the proposed approach.