A COMBINED SPEED AND FINITE-TIME YAW CONTROLLER FOR AN UNDERACTUATED UNMANNED SURFACE VESSEL USING WAY-POINT NAVIGATION

摘要

This paper focuses on the speed and yaw control problem for an underactuated unmanned surface vessel (USV) with only two propellers navigating through multiple way-points using the line-of-sight (LOS) algorithm. The speed and yaw dynamics are transformed into a cascaded nonlinear system that can be reduced to the stabilization control problem of the surge and yaw subsystems. The proposed surge speed controller uses a distance and heading error feedback control to vary its speed accordingly while the heading subsystem is stabilized via a finite-time controller. Comparisons of the traditional yaw rate stabilization control techniques are made with the proposed finite-time controller and shown to be inferior to the finite-time controller in terms of convergence rate and robustness. The stability and effectiveness of the proposed control system is demonstrated and validated by simulation results of a modeled kayak.