Nonlinearmodelpredictivecontrol of dynamic positioning of deep-sea ships with a unified model

Abstract

In this paper, a six degrees-of-freedom unified model of ship is established based on one dynamic positioning (DP) vessel, in which sea environment models of wind, current and waves are included. Then, the controller of DP ship based on a kind of nonlinear model predictive control algorithm is designed. By choosing an appropriate predictive period, the DP ship can move to the desired position and heading quickly and accurately. Finally, the stability of the developed control system for dynamic positioning of ships is proved by theoretical and simulation studies.