Dynamic Analysis and Motion Control of an Underactuated Unmanned Surface Vehicle (WL-II)

Abstract

AbstractAn unmanned surface vehicle (USV) is a promising maritime motion platform used to accomplish hundreds of different tasks. This paper presents a design, improved dynamic modeling, and motion control of an underactuated USV, called WL-II. The detailed structure and component of WL-II are studied first. Then based on WL-II's structure, kinematic and dynamic models are built considering wind as well as sea waves; thus, a nonlinear dynamics model is deduced in the form of a state equation. The hardware and software systems of WL-II are introduced for its control mechanism. Then, the adaptive sliding mode control (SMC) algorithm for WL-II's motion is examined. The simulation and experimental results validate the superior performance of the proposed algorithm for WL-II's heading control to the regular SMC method. In this paper, improved dynamics, which consider more parameters (wind and sea waves), are proposed and reasonably simplified for computation. The adaptive SMC is used to control WL-II's motion to improve control precision and reduce response time.