|Path Following of Underactuated Unmanned Surface Vehicle Based on Trajectory Linearization Control with Input Saturation and External Disturbances
Bingbing Qiu, Guofeng Wang*, Yunsheng Fan, Dongdong Mu, and Xiaojie sun
International Journal of Control, Automation, and Systems, vol. 18, no. 8, pp.2108-2119, 2020
Abstract : This paper investigates the path following control problem for underactuated unmanned surface vehicle (USV) in the presence of unmodeled dynamics, external disturbances and input saturation. A novel adaptive robust path following control scheme is proposed by employing trajectory linearization control (TLC) technology and finite-time disturbance observer, which is composed of a concise yaw rate controller and a surge speed controller. The salient features of the proposed scheme include: a path following guidance law is designed to ensure USV effectively converging to and following the desired path; TLC is introduced into the field of USV motion control as new effective technique, and it is the first time used to design path following controller for underactuated USV;
a finite-time nonlinear tracking differentiator is constructed not only to avoid the signal jump caused by derivation, but also to filter noise and high frequency interference. A finite-time disturbance observer (FDO) is devised to exactly observe the uncertain dynamics and unknown external disturbances, which improves the tracking accuracy and precise disturbance rejection of the proposed controller; then, an auxiliary dynamic system that is governed by smooth switching function is developed to compensate for the saturation constraint on actuator. Stability analysis
verifies that all signals in the closed-loop system are uniformly ultimately bounded. Finally, simulation results and comparisons illustrate the superiority of the proposed control scheme.
Auxiliary dynamic system, finite-time disturbance observer, finite-time nonlinear tracking differentiator, path following, trajectory linearization control technology, underactuated USV.