Event-triggered Adaptive Fuzzy Consensus Tracking Control For Uncertain Multi-agent Systems

In recent years,due to the wide application of multi-agent system collaborative control in the field of practical engineering,as a typical collaboration behavior,consensus has attracted increasing attention from researchers.At the same time,with the continuous development of industry,the practical multi-agent systems are becoming more and more complex,which are often characterized by uncertainty,nonlinearity,state unmeasurable,output constraints and fractional-order dynamics.In addition,distributed consensus control needs to acquire neighbors’ information through the network to complete complex tasks.However,microprocessors equipped by agents for receiving information often have limited communication bandwidth and computing ability.Therefore,this paper will use event-triggered control,adaptive control,fuzzy logic system,barrier Lyapunov function,backstepping approach,dynamic surface control technique to study the consensus tracking control problem of uncertain nonlinear multi-agent systems with output constraints and fractional-order dynamics.The main work is as follows:1.A distributed event-triggered adaptive fuzzy consensus tracking control scheme is proposed for a class of uncertain nonlinear multi-agent systems with output constraints.In order to overcome the possible poor transient performance caused by the discontinuous control input,an exponential dependent barrier Lyapunov function is introduced to achieve the constraint of the consensus tracking error bound and its convergence speed.In addition,by establishing a fuzzy state observer within each agent about itself and its neighbors,not only the strict assumption that the full-state measurements can be measured is avoided,but also the transmission of information is decreased and the communication burden is further reduced.Then,the controller is designed under the framework of backstepping combined with dynamic surface control technology,and it is proved by Lyapunov stability theory that the proposed control strategy can guarantee the boundedness of system signals.Finally,the simulation results further confirm the correctness of the designed control scheme.2.A distributed event-triggered adaptive fuzzy consensus tracking control scheme is proposed for a class of uncertain nonlinear multi-agent systems with fractional-order dynamics.In order to avoid the problem that the trigger mechanism with relative threshold will produce large control impulse when the control signal jumps suddenly,a decreasing threshold function about time is designed.In addition,to overcome the effect on the overall tracking performance of the distributed control scheme,the agent can only rely on the neighbor information for coordination.For the agent that can not receive the leader information directly,the fractional-order adaptive law about the reference trajectory is introduced into its control function by using the consensus tracking error to achieve better tracking performance.At the same time,the strict assumption that the fractional-order derivative of virtual control function is known is removed by constructing fractional-order filter.Then,the controller is designed in the framework of backstepping,and the fractional stability criterion is used to prove that the proposed control scheme can guarantee the boundedness of all system signals.Finally,the simulation results further prove the correctness of the proposed method.