Research On Leader-Following Consensus Control Problem For Nonlinear Multi-Agent Systems

In recent years,the cooperative control of multi-agent system has been widely concerned.Different from single system,multi-agent system can be widely used in many fields,such as unmanned vehicle formation,cluster and distributed sensor network,cooperative monitoring,robot cluster and so on.In addition,cooperative control has the following basic aspects,such as the consensus control depends on the interaction between agents,the formation control based on multi-information fusion and the containment control with multiple dynamic leaders.Among them,the leader-following consensus problem means that the follower agent can follow the leader agent's dynamic,and the tracking error converges to a small neighborhood near the origin.Containment control is the extension of leader-following consensus control in the case of multiple leaders,which can ensure that all follower agents converge to the dynamic convex hull formed by multiple leader agents.Based on the above,this paper will study the leader-following consensus problem of nonlinear multi-agent system based on backstepping method with adaptive control and fuzzy logic system.To be specific,1)The consensus problem of adaptive leader-following control for multi-agent systems with dead zone and input delay is studied,simultaneously.The second-order tracking differentiator is introduced to avoid the repeated differentiation of the virtual controller.The dead-zone problem is solved by using the dead-zone slope and boundary value theory.Based on Pade approximation,the impact of input delay is negatived.The tracking error converges to the neighborhood near the origin,and the designed controller can ensure that all signals in the closed-loop system are semi-globally uniform and ultimately bounded(SGUUB).2)The adaptive fuzzy event-triggered consensus control of multi-agent systems with prescribed performance and input quantization is studied.Based on the prescribed performance function and input quantization decomposition method,a new adaptive fuzzy event-triggered consensus protocol is proposed,and it can only be triggered when the event-triggered error exceeds the prescribed threshold,which can save limited communication resources.It is shown that the control scheme can ensure that all signals in the system are SGUUB.Meanwhile,the tracking error converges to the prescribed limit.3)Based on the technique of disturbance observer,the control problem of a nonlinear multi-agent system subject to unknown disturbances and prescribed performance is studied.By using adaptive compensation technology,a new distributed control scheme is proposed without considering the unknown disturbance boundary value.In addition,Nussbaum function is used to deal with the unknown control coefficient caused by the nonlinearity of the output mechanism.The outputs of followers converge in the convex hull formed by multiple dynamic leaders.The results show that all signals are SGUUB,and the local neighborhood containment error can converge to the prescribed boundary.