Research On Event-triggered Control Of Several Classes Of Nonlinear Systems

It is well known that nonlinear systems exist widely in practical control systems.Therefore,the study of nonlinear systems has attracted extensive attention of scholars.However,due to the existence of unknown nonlinear function,it is more difficult to study nonlinear systems than linear systems.With the development of nonlinear control techniques,the backstepping control has increasingly become a powerful tool to deal with nonlinear systems.At the same time,with the development of network control,how to save communication resources and reduce the burden of communication are becoming increasingly urgent issues for scholars while ensuring acceptable system performance.Therefore,in recent years,adaptive control of nonlinear systems based on event-triggered mechanism has become a research hotspot in the field of control.In this paper,by combining backstepping design and event-triggered control technology,the effective design schemes of adaptive tracking controllers are designed for uncertain nonlinear systems,stochastic nonlinear systems,and uncertain nonlinear timedelay systems,respectively.The designed controllers can not only ensure that the tracking error of the system converges to any small neighborhood of zero,but also save communication resources and reduce communication burden.The main contents of this paper include the following aspects:In the first part,the research backgrounds of this paper are briefly introduced,and the main results of this paper are proposed;In the second paper,an event-triggered fuzzy tracking controller is designed for a class of stochastic nonlinear systems.To realize the finite-time command filtering control of stochastic nonlinear systems,a new compensation signal system is designed.It is proved theoretically that the proposed controller can not only guarantee that all closed-loop signals are bounded,but also ensure that the output signal of the system can track the reference signals in any small neighborhood of zero.At the end of this part,a practical simulation example is given to prove the feasibility of the designed controller;In the third part,an event-triggered neural network control scheme based on command filtering is proposed for a class of uncertain nonlinear time-delay systems.Different from the event-triggered control scheme proposed in the existing kinds of literature,the proposed control scheme solves the problem of the complex explosion caused by repeated derivation of virtual controllers in nonlinear time-delay systems.It is proved from theory and simulation that the proposed control scheme can ensure that the tracking error of the system converges to any small neighborhood of zero;In the fourth part,the event-triggered control problem is studied for a class of uncertain nonlinear systems with unknown control direction.The fuzzy logic system is employed to approximate unknown nonlinear function.The Nussbaum function is used to deal with the problem of unknown control direction.A new event-triggered controller is designed by combining backstepping design.In addition,two different event-triggered mechanisms are proposed and the corresponding stability analyses are given.At the end of this section,the simulation example is given to prove the effectiveness of the designed controller.