A LOS-Based Path-Following Control of Underactuated Autonomous Surface Vessels for Time-Varying Formations: Theory and Experiment

This article investigates the cooperative curved path-following problem of underactuated autonomous surface vessels (ASVs) in time-varying formations. The proposed cooperative guidance strategy consists of the individual guidance law of heading angle and total velocity and the tracking differentiator-based virtual control inputs. Specifically, the former is developed through a novel line-of-sight (LOS) guidance method to guide ASVs to their desired positions, enabling the achievement of time-varying formations; The latter are designed for each ASV to ensure accurate tracking of the guidance signals. The along- and cross-tracking error system is asymptotically stable under the proposed individual guidance law, and the input-to-state stability of the tracking error systems under the proposed virtual control inputs are proved by rigorous theoretical analysis, respectively. Finally, numerical simulations and experimental results are conducted to validate the effectiveness of the proposed cooperative guidance strategy for path-following over a parameterized curve.