Adaptive Fuzzy Control Of Uncertain Switched Nonlinear Systems

In recent years,with the rapid development of modern computer technology,which provides the powerful technical support and broad prospects for the research of switched systems,adaptive fuzzy control of switched nonlinear systems has become a hot research topic in the field of control,and the study of such systems has important theoretical and practical significance.For two classes of uncertain switched nonlinear systems,and by using backstepping and adaptive fuzzy control technology,this thesis studies the problems of the controller design methods and stability analysis of the corresponding closed-loop systems.The main contents of this thesis are listed as follows:1.First,the adaptive fuzzy output tracking control problem for a class of uncertain nonlinear switched lower triangular systems with time-delays and output constraints is investigated.In the process of design,the common Lyapunov function method,backstepping technology,and barrier function are applied to construct a state feedback controller for the considered system such that all closed-loop signals are bounded and the system output eventually converges to a small neighborhood of the desired reference signal without transgression of the constraint.2.Second,the problem of observer-based adaptive fuzzy control for a class of nonlinear time-delay systems in non-strict-feedback form is studied.In the process of design,adaptive fuzzy approach,backstepping and Lyapunov-Krasovskii functionals are used to construct a controller.The proposed adaptive fuzzy output feedback controller guarantees that all the signals in the adaptive closed-loop system are semi-globally uniformly ultimately bounded.Although adaptive fuzzy controller design of uncertainty switched nonlinear systems in this thesis is initially explored,there are still many open problems to be resolved,such as state-dependent switching signals design for adaptive fuzzy control problem of switched nonlinear systems,adaptive fuzzy control problem of switched stochastic non-strict nonlinear systems,and related engineering applications,etc.