Summary
This paper develops a novel fuzzy adaptive backstepping dynamic surface control scheme for a class of strictâfeedback nonlinear systems with unknown time delay based on adaptive dynamic programming. The whole control scheme is composed of 2 parts, ie, feedforward control and feedback optimal control. Fuzzy logic systems are used to identify nonlinear systems. The control design method, which combined the backstepping design technique and the dynamic surface control approach, is applied to convert triangular structure systems to affine nonlinear systems; it not only can solve the problem of âexplosion of complexityâ but also can avoid the appearance of unknown terms. The closedâloop system is guaranteed to be uniformly ultimately bounded based on the Lyapunov and optimal control theory, and the system output can track the desired reference signal in an optimal manner. The simulation results of numerical examples are presented to show the effectiveness of the proposed approach.