Disturbance Observer-Based Disturbance Attenuation Control for Dynamic Positioning System of Ships

Abstract

The anti-disturbance control problem is addressed for dynamic positioning (DP) system of ships affected by the ocean disturbances. The ocean disturbances consist of slowly varying environmental disturbances and a class of long peak wave disturbances in mature period. The stochastic disturbance observers are constructed to estimate them online, respectively. On this basis, a novel disturbance observer-based disturbance attenuation control (DOBDAC) strategy is proposed to ensure that all signals of DP composite system are asymptotically bounded in mean square. Finally, the feasibility of the control strategy is verified by a simulation research on the supply ship.