Observer-based Adaptive Fuzzy Control for Uncertain Nonlinear time-delay systems

This work studies an observer-based fuzzy adaptive control problem for the uncertain nonlinear time-delay systems with unknown virtual and actual control gain functions. The Lyapunov-Krasovskii function is utilized to eliminate the unknown time delays. In order to estimate the uncertain nonlinear functions, Fuzzy Logic Systems(FLSs) are quoted. Then the fuzzy state observer is devised to handle the unavailable state issue. By using the backstepping control technique and bounded control method, a novel observer-based fuzzy adaptive backstepping control approach is developed. The rationality of the presented control methods is demonstrated by means of the Logarithm Lyapunov functions.