Fuzzy approximation-based model reference adaptive control of nonlinear systems

Based on the universal approximation capability of the Takagi-Sugeno (TS) fuzzy systems, we present a solution to the model reference control of continuous-time nonlinear system problem. Using the assumption that a fuzzy model exists for the considered nonlinear systems class, a direct TS fuzzy adaptive controller is designed to achieve the tracking objective. It is not required to estimate the fuzzy model; only its existence assumption is required. It is proved; using Lyapunov stability tools, that this adaptive scheme is asymptotically stable and the tracking error converges to zero. Simulation results illustrate the proposed algorithm performance.