Adaptive fuzzy control for a class of MIMO nonaffine nonlinear systems

A robust adaptive fuzzy control scheme is presented for a class of multiple-input-multiple-output (MIMO) nonaffine nonlinear systems with modeling uncertainties and external disturbances by using backstepping approach. The fuzzy logic systems are introduced to estimate the unknown nonlinear functions, the approximation errors of fuzzy systems are only required norm-bounded, and additional adaptive terms are employed to balance approximation errors and disturbances. The main characteristics of this scheme are that the number of the online adaptive parameters is no more than two times of the order of system and the tracking errors are proven to a small neighborhood of the desired trajectories. Hyperchaotic Rössler system is presented to illustrate the feasibility and effectiveness of the proposed control technique.