Distributed formation control with obstacle avoidance for multiple underactuated unmanned surface vehicles

This paper investigates the problem of distributed formation control with obstacle avoidance for multiple underactuated unmanned surface vehicles (USVs). Firstly, a distributed velocity observer is designed as the guidance system for each follower USV to estimate the velocity of the leader. Secondly, the artificial potential function is introduced into the local formation tracking error. A distributed virtual control command is developed based on refined formation error and estimated velocity. Thirdly, thrust control law and reference angular velocity are derived by introducing auxiliary input through the transverse function method. The radial basis function neural networks are employed to approximate the nonlinear damping terms in the vehicle kinetics. Fourthly, the robust yaw moment control law is designed by utilizing the backstepping technique. The boundedness of all signals in the closed-loop system and the safety performance are analyzed by Lyapunov stability theory. Finally, simulation results are presented to verify the proposed method.