Consistent Output Regulation Of Nonlinear Multi-agent Systems

The consensus output regulation problem is mainly used to study how all agents achieve consensus under the condition of limited local information exchange,whose main task is to design a consensus control protocol based on local information exchange such that the states of all agents reach a common state value.In real production process,exogenous disturbance exists generally,which is the main reason for the poor stability and performance of the system.And the disturbance is often unknown and does not have explicit expression.In addition,since the control direction of each agent is not always known in advance,this brings a new challenge to solve the problem of consensus output regulation of multi-agent systems.For this purpose,the design of control protocol and the stability analysis of these two classes of nonlinear multi-agent systems are investigated in this paper.The main contributions are as follows:1.In this paper,the consensus control of unknown nonlinear multi-agent systems with unknown disturbances under undirected networks is investigated.Firstly,a novel distributed adaptive consensus control protocol and disturbance observer are proposed based on relative output information.Different from the existing disturbance rejection methods,only the relative output information is used for disturbance observer,and only the part of disturbance that affects the common trajectory will be rejected.Secondly,a novel lemma is proposed to design a consensus control protocol for the multi-agent systems.Finally,the stability analysis of the systems is carried out by using Lyapunov function.The outcome is that all variables of the multi-agent system are bounded and the output regulation errors of the subsystems converge to zero asymptotically.2.We study the global robust output regulation for a class of high-order unknown nonlinear multi-agent systems with unknown control directions in this paper.Firstly,a Nussbaum-type function is adopted to resolve the problem of unknown control directions.Then,based on relative output information,a novel distributed adaptive consensus control protocol is proposed by using the sign function.Finally,by selecting appropriate Lyapunov function candidate,the boundness of all variables in the closed-loop system is proved,and all followers can asymptotically track the leader's state trajectory in the presence of exogenous disturbances.3.In this paper,the consensus output regulation of a class of high-order nonlinear multi-agent systems with unknown exogenous disturbances under undirected networks is investigated.Moreover,the control directions are supposed to be completely unknown.By introducing hyperbolic tangent function and Nussbaum gain function,a novel distributed adaptive consensus control protocol is designed based on relative output information.The stability analysis of the systems is carried out by selecting appropriate Lyapunov function.Finally,a simulation example of van der Pol oscillator is given to prove that the stability of the system has been further improved under the proposed consensus control protocol,and the tracking performance of the system has been greatly improved.