Distributed Edge-event Triggered Formation Control for Multiple Unmanned Surface Vessels with Connectivity Preservation

In this paper, the distributed formation control problem for unmanned surface vessels (USVs) with sensing range and communication resource constraints is investigated. An edge-event triggered sliding mode controller is developed to achieve formation-keeping maneuver. Firstly, in order to preserve the prescribed communication connectivity, a combination of artificial potential function technique and the sliding mode surface is adopted in controller design process. Subsequently, considering the limited communication resource, the edge-event triggered control method is introduced to design triggering condition related to the information of every edge. Different from the traditional node-based event-triggered control mechanism, each member only transmits its state information to its out-neighbours asynchronously once the edge between them is triggered, such that the communication cost can be further reduced. The theoretical results exhibit that all signals in the closed-loop system are bounded. Eventually, by resorting to numerical simulations, the validity of the proposed controller is demonstrated.