An improved line-of-sight guidance law for path following of Unmanned Surface Vehicle based on adaptive lookahead distance

This paper proposes an improved line-of-sight (LOS) guidance law for path following of Unmanned Surface Vehicle (USV) based on adaptive lookahead distance. The adaptive lookahead distance guidance algorithm of path following is designed as a new function of the USV's cross tracking error to adjust the lookahead distance with less parameters and less initial lookahead distance, so that the USV reach the desired path quickly and stably in both straight-line and curve guidance. In the experiment, it is compared with other algorithms using the PID controller and Qihang USV model. The simulation results show the effectiveness of the adaptive lookahead distance algorithm in both straight-line and curve desired path. Compared with other guidance algorithms, the improved adaptive LOS guidance algorithm reaches the desired path faster for the first time and is closer to the desired path after stabilization.