| Most physical systems often have various strong nonlinearities in practical industrial applications.For such complex dynamic systems,it is significant to find a species of nonlinear control method with fast response,simple structure and strong robustness to ensure the performance index of the controlled system,which has always been the focus of scholars'research work.Since the fuzzy control method was put forward,T-S fuzzy modeling has been regarded as an effective method to study this kind of complex nonlinear dynamic systems.Many achievements have been produced in this aspect.On the other hand,many practical nonlinear systems are actually controlled in the network environment with the rapid development of modern computer field.As a consequence,communication overload,large amount of calculation and huge waste of resources generally exist in such networked control systems.Event-triggered communication strategy is an effective solution to tackle these interferences.The controller reduction technology has also been sustainably developed since the dimension of the controller in the actual system should not be too high.Low-order controllers have lower computational complexity and achieve better control quality,which are easier to implement.It is noted that most of the existing research results of event-triggered communication scheme are aimed at linear systems,and the research of nonlinear event-triggered control is more worthy of study.Among them,the event-triggered collaborative control based on T-S fuzzy model has generated some achievements,but it still requires further improvement and perfection.On the basis of the existing research results of fuzzy control methods,this paper takes the discrete-time T-S fuzzy model as the basic research object,introduces the event-triggered communication mechanism,further expands the collaborative design method of fuzzy control and event-triggered communication strategy,and successfully applies it to the single manipulator system.Finally,the research content is extended to the controller reduction.The specific research contents of this paper are as follows:(1)The state feedback controller design problem for discrete-time T-S fuzzy systems under event-triggered communication strategy is studied.For a class of discrete-time T-S fuzzy systems,based on the parallel distributed compensation ideology,the controller is designed by state feedback,which makes the corresponding dynamic augmented system satisfy the asymptotic stability under H_?performance index.The controller design algorithm is obtained by strict theoretical derivation,and the effectiveness is verified by a numerical simulation.(2)The output feedback controller design problem for discrete-time T-S fuzzy systems under event-triggered communication strategy is studied.In view of the outstanding advantages of event-triggered communication strategy and the practical effect of output feedback control technique,the ultimate closed-loop system is constructed by considering the event generator,time-varying interval delay and data packet loss rate simultaneously.By selecting the appropriate Lyapunov function,a less conservative mean-squared asymptotic stability condition is obtained,which has predetermined performance index,and the output feedback controller parameters are designed.Finally,the feasibility and effectiveness are verified by a single manipulator system simulation.(3)The controller reduction problem of fuzzy output feedback controller with predetermined performance index is studied.Based on the high-order output feedback controller of T-S fuzzy system,the reduced-order fuzzy controller is designed directly,and the error system is constructed.By using projection theorem and cone compensation linearization algorithm,the reduced-order parameters of the controller are obtained.Simulation results show that the designed fuzzy output feedback controller can not only achieve the control effect of general fuzzy control method,but also reduce the controller order and achieve the control goal better. |
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