Consider the problem of memoryless state feedback controller for time-delay system, which cannot consider both the memoryless and the memory items in the system. Therefore, the memoryless state feedback controller has certain limitations and is more conservative. This paper addresses the memory state feedback control for the time-varying delay switched fuzzy systems based on T-S fuzzy model to overcome the problem discussed above. The state vector and input of the time-varying delay systems contain unknown time-varying delay with known bounds. The designed controller whose parameters are solvable can introduce past state information and reduce the system conservativeness. The more general Lyapunov-Krasovskii functional is selected and the switching law is designed in order to analyze the open-loop system stability, and the memory state feedback controller is designed for the closed-loop system and the criterion for its asymptotic stability. Discuss the solvability of the above two criteria. Finally, a numerical example is given. The simulation results show that the proposed method is more feasible and effective.

Observer-based robust tracking control for a class of switched fuzzy (SF) systems with time delay is investigated in this paper. An SF system, which differs from the existing systems, is first employed to describe a non-linear system. Next, a fast switching controller consisting of a number of simple sub-controllers is proposed. The designed controller based on measured output instead of the state information integrates the advantages of both the linear and switching state-feedback controllers but eliminates their disadvantages. Tracking hybrid control schemes, which are based upon a combination of the H_∞ tracking theory, fast switching control algorithm and switching law design, are developed such that the observer-based H_∞ model reference tracking performance is guaranteed. Sufficient conditions for the solvability of the tracking control problem are given for the case in which the state of system is not available. Since convex combination techniques are used to derive the delay independent criteria, some subsystems are allowed to be unstable. Finally, various comparisons of the elaborated examples are performed to demonstrate the effectiveness of the proposed control design approach.

Stability issues for switched systems whose subsystems are all Sugeno fuzzy discrete-time systems are studied and new stabilization control results derived. Innovated representation models for switched fuzzy systems are proposed. The single Lyapunov function method has been adopted to study the stability of this class of switched fuzzy systems. Sufficient conditions for quadratic asymptotic stability are presented and stabilizing switching laws of the state-dependent form employed in PDC scheme are designed. Illustrative examples demonstrate the effectiveness and the feasible performance of the proposed synthesis through the respective simulation results.

This paper addresses the problem of designing robust tracking controls for a class of switched fuzzy (SF) systems with time delay. A switched fuzzy system, which differs from existing ones, is firstly employed to describe a nonlinear system. Next, a fast switching controller consisting of a number of simple subcontrollers is proposed. The smooth transition is governed by using the fast switching controller. Tracking hybrid control schemes which are based upon a combination of theH_∞tracking theory, fast switching control algorithm, and switching law design are developed such that theH_∞model referent tracking performance is guaranteed. Since convex combination techniques are used to derive the delay independent criteria, some subsystems are allowed to be unstable. Finally, various comparisons of the elaborated examples are conducted to demonstrate the effectiveness of the proposed control design approach. All results illustrate good control performances as desired.