Formation control and collision avoidance of unmanned water surface vehicles in maritime environments

Abstract

The formation control of a team of unmanned water surface vehicles (USVs) experiencing maritime environmental disturbances is investigated. These perturbations include water waves, ocean current, wind gusts, communication and measurement errors, and other unmodeled dynamics that are captured through stochastic noise. A distributed control scheme leveraging local communication among team members is proposed to drive the group towards a set of waypoints while simultaneously achieving a desired spatial configuration and collision avoidance. The exponential mean square convergence of the proposed control scheme is shown under a version of the Lyapunov stability theory adapted to stochastic systems. Closed form expressions are proposed to estimate model parameters from experimental data collected in operating environments. The effectiveness of the proposed formation control scheme and collision avoidance method is assessed through numerical simulations demonstrating the interplay between the control parameters and the intensity of the noise. It also highlight the crucial role of the stochastic noise in resolving potential singularities or deadlocks in the vehicles’ motion , which originate from the collision avoidance forces.