LADRC-based wake tracking control via sideslip angle estimation for AUVs following the trajectories of near-surface targets

Abstract

Autonomous underwater vehicles (AUVs) face considerable challenges in tracking the trajectories of near-surface targets due to nonlinear couplings, environmental disturbances, and pronounced sideslip effects, all of which significantly degrade the stability and accuracy of their control systems. In this paper, a wake-tracking control method is proposed for AUVs following the trajectories of surface targets. The controller integrates sideslip angle estimation with active disturbance rejection. A reduced-order extended state observer is constructed to estimate the real-time sideslip angle, representing the deviation between the vehicle's heading and its actual motion direction caused by wake-induced disturbances. Furthermore, a sideslip-estimation-based line-of-sight (LOS) guidance law is developed to generate coordinated yaw angle and surge velocity commands, thereby improving both directional control and speed regulation during wake tracking. Two linear active disturbance rejection controllers are subsequently designed to achieve decoupled and robust control of the yaw and surge channels. Simulation results demonstrate that the proposed method surpasses conventional LOS guidance and PID controllers integrated with disturbance observers in trajectory accuracy, lateral deviation suppression, convergence rate, and energy efficiency, thereby enabling stable and reliable wake tracking for AUVs in complex near-surface marine environments.