Anti-interference And Fault-tolerant Control Of Underwater Robot System Based On TS Fuzzy Mode

Recently,the exploration for ocean resources has greatly promoted the development of unmanned surface vehicle(USV).However,due to the complexity of the ocean environment,the control performance of the USV system is required to be higher.The USV system can be affected by external disturbance,actuator and sensor faults,so it is a challenging task to improve the anti-disturbance ability and fault-tolerant ability of the USV system.This paper proposes several fuzzy anti-disturbance fault-tolerant controllers for Takagi-Sugeno(T-S)fuzzy USV with external disturbance,which makes the USV systems have better anti-disturbance performance and fault-tolerant ability.The work of this paper can be summarized into the following three parts:Firstly,the sampled-data output feedback anti-disturbance fault-tolerant controller for USV system with actuator fault is investigated.First,the T-S fuzzy model is used to model the USV system,and the extended state observer and disturbance observer are designed to obtain states,actuator faults and disturbance estimations.Next,using the outputs of the two observers,a T-S fuzzy sampled-data anti-disturbance controller is designed.Then based on the Lyapunov stability theory,the closed-loop system is asymptotically stable and satisfies H_∞performance,while using the linear matrix inequality(LMI)technique,sufficient condi-tions are obtained for the solvability of the observer and controller gains.Finally,simulation results confirms the effectiveness of the controller.Secondly,the dynamic event-triggered anti-disturbance fault-tolerant control for USV system with actuator fault is studied.First,a dynamic event-triggered mechanism is pro-posed for USV system based on T-S fuzzy model.Next,state observer and disturbance observer is designed based on output of event-triggered generator to estimate states and dis-turbance.Then an adaptive law is designed to estimate the actuator fault and an adaptive event-triggered anti-disturbance fault-tolerant control is proposed.The convergence of the closed-loop system is guaranteed and the output of system satisfies H_∞performance.The event-triggered mechanism excludes zeno behavior.Finally,the effectiveness of the control strategy is demonstrated by simulation.Thirdly,the dynamic event-triggered anti-disturbance fault-tolerant control for USV sys-tem with actuator and sensor faults is discussed.First,in order to obtain system states,ac-tuator and sensor faults,and external disturbance estimations,the extended state observer and disturbance observer are designed for T-S fuzzy USV system.Next,using the outputs of the two observers,a dynamic event-triggered anti-disturbance fault-tolerant controller is designed.Then based on the Lyapunov stability theory,the convergence of all signals in the closed-loop system is proved,and the event-triggered mechanism excludes zeno behavior.With LMI technique,sufficient conditions are obtained for solving controller gain.Finally,the simulation results verify the effectiveness of the proposed scheme.