Leader-follower formation control of fully actuated USVs with prescribed performance and collision avoidance

This paper addresses robust leader-follower formation control problem with prescribed performance and collision avoidance for a group of fully actuated unmanned surface vehicles (USVs). The dynamic surface control (DSC) technique is employed to introduce a first-order low-pass filter in the kinematic design such that the utilization on the leader vehicle's acceleration is avoided in the kinetics control design. Both modelling uncertainties and external disturbances are discussed, in which they are lumped together and an observation mechanism is presented to estimate the total disturbances. Subsequently, disturbance-observer-based formation controller is designed using backstepping procedure, error transformation, and Lyapunov synthesis. The proposed formation controller ensures uniformly ultimate boundedness of all closed-loop signals with guaranteeing prescribed performance of formation errors and avoids the collision between the follower and its leader. Simulation results demonstrates the effectiveness of the proposed controller.