Swarm Control of Multiple Unmanned Surface Vehicles with Unknown Time-Varying Environmental Disturbance and Input Saturation Constraints

This study develops a formation-tracking control scheme for a group of unmanned surface vehicles (USVs) operating in the presence of time-varying environmental disturbances and actuator saturation. The control task requires the follower vessels to track a virtual navigation vessel, preserve the prescribed formation geometry, and simultaneously satisfy obstacle-avoidance requirements. To cope with unknown external effects, a finite-time disturbance observer is incorporated to reconstruct the environmental disturbances. The discrepancy caused by actuator saturation is handled through an auxiliary dynamic compensation mechanism. On this basis, these components are integrated into a state-feedback control law for coordinated formation tracking. A Lyapunov-based analysis is carried out to establish the stability properties of the resulting closed-loop system. Numerical simulations further demonstrate the formation-tracking performance and the effectiveness of the proposed control architecture under disturbance and saturation effects.