Equilateral triangular formation of unmanned surface vehicles for target tracking with event-triggered collision avoidance

Abstract

Multiple cooperative unmanned surface vehicles (USVs) offer enhanced capability than a single USV for complex missions. In this paper, the multi-objective control problem of target tracking by equilateral triangular formation of underactuated USVs with collision avoidance between USVs as well as between the USV and the target is addressed with the distance-based approach. A novel control algorithm with event-triggered collision avoidance is designed to accelerate formation shape convergence and reduce actuator activity to achieve a better trade-off between different control objectives. “Rotational forces” are introduced to the control law so that the formation turns to a prescribed orientation to guarantee avoiding collisions with the target in the tracking process with the least amount of control efforts. The gradient-property of the proposed control system and global convergence to the desired shape are proven. Finally, the effectiveness of the proposed formation tracking control with event-triggered collision avoidance is verified by simulation.