Research On Distributed Formation Control Algorithm Of Multiple Unmanned Ships Based On Event Triggering

In the process of implementing the traditional continuous distributed formation control algorithm for the multi-unmanned surface vehicles(multi-USVs)system,there is frequent communication between USVs and controller of USVs update continuously.In order to reduce the requirements for communication bandwidth and controller performance in the process of algorithm execution,this paper designs a distributed event-triggered formation control algorithm for multi-USVs by introducing the event-triggered mechanism.On the basis of ensuring the formation control of multi-USVs,the communication volume between USVs and the update frequency of the controller during the algorithm execution are effectively reduced.Firstly,an event-triggered distributed formation control algorithm for multi-USVs is proposed in this paper.By introducing a virtual leader,set its desired trajectory.An event-triggered formation controller based on the dynamics model of USV is designed by using event-triggered state measurement error.The followers can track the virtual leader while maintaining a fixed desired relative distance from it to form the formation.The USVs communicate only when the event-triggered measurement error exceeds its threshold,which realizes intermittent communication among the multi-USVs system.Through theoretical analysis,it is proved that the algorithm can realize formation control of multi-USVs,and there is no Zeno behavior.Then,in order to simplify the design of the controller,an event-triggered distributed formation control algorithm based on observer for multi-USVs is proposed in this paper.By designing the observer to estimate the leader’s state information,and taking the observer state information as the expected state value of USVs,the tracking controller of USVs is further designed to track the state information of the observer to realize the formation.The observer only communicates when the event is triggered.In order to realize the intermittent update of the USVs controller,on the basis of the distributed formation algorithm based on the event-triggered observer,an improved distributed event-triggered formation algorithm is designed.The event-triggered mechanism is introduced into the controller of USVs tracking observer to observe the state to realize the event-triggered control process of USVs.Finally,the intermittent communication and intermittent update of the controller in the formation control process of USVs are realized.The algorithm is analyzed theoretically by Lyapunov stability analysis method,and verified by MATLAB simulation experiment.