Fixed-time Cooperative Path Following of Multiple USVs Based on Event-triggered Communication

In this paper, an event-triggered communication based fixed-time cooperative path following algorithm is proposed for multiple unmanned surface vessels(USVs). Firstly, the structure of the control system is presented. By modularization design, the cooperative path following problem of multiple USVs is transformed into two problems, i.e. the fixed-time parameter coordination problem and the fixed-time trajectory tracking problem. After that, the fixed-time parameter coordination algorithm and the fixed-time trajectory tracking algorithm are proposed. The function of the parameter coordination algorithm is to coordinate parameters of USVs on the expected path, so as to calculate an ideal position for each USV. The function of trajectory tracking algorithm is to make USVs tracking the ideal position generated by the parameter coordination algorithm in real time. The algorithm of each module can guarantee fixed-time convergence, so the whole system can realize fixed-time convergence. In order to reduce the communication burden, the event-triggered communication strategy is adopted for the parameter coordination module. Sufficient conditions for realizing the control objective are given. Effectiveness of the proposed results is confirmed by simulation.