Adaptive fuzzy tracking control for nonlinear strict-feedback systems with unmodeled dynamics via backstepping technique

摘要

This paper considers an output tracking control problem with unmodeled dynamics for a class of nonlinear strict-feedback systems, which possess unstructured uncertainties and dynamic disturbances. Uncertain nonlinearities contain both unmeasured states and measurable output. A direct tracking controller is obtained on the basic of the backstepping and fuzzy logic system. By the use of small-gain approach, the discussed closed loop system is proved to be input-to-state practically stable (ISpS) and all the parameter signals are semi globally uniformly ultimately bounded. There are three adaptive parameters in the fuzzy controller. Finally, simulation examples are given to illustrate the efficiency of the proposed approach.