Robust tracking control of T-S fuzzy systems based on fuzzy Lyapunov approach

This paper addresses the problem of robust tracking control for nonlinear systems with external disturbances. The nonlinear system is represented by the discrete-time Takagi-Sugeno (T-S) fuzzy model. The control scheme is based on H_infin performance to attenuate the tracking error as small as possible for the external disturbances. The stability of the whole closed-loop model is investigated using the fuzzy Lyapunov function. Sufficient conditions are derived in terms of a set of bilinear matrix inequalities (BMIs). The key point of the proposed approaches is to apply the fuzzy Lyapunov function in the discrete-time robust tracking control problems. The simulation results show the effectiveness of the proposed method.