Reaction to Disturbance During the Berthing Maneuver of an Automatic Control System with Decoupling Control

Abstract

In the control of ships, it is important that the system not only be able to perform the desired task (tracking control), but that it also be able to compensate for such factors as wind, waves, and currents (disturbance control). Both types of variables must be factored into any control system. An automatic control system with decoupling control for berthing maneuvers was previously proposed ; however, the control system was not tested for its performance in compensating for disturbances. In this study, we analytically show the fundamental characteristics of the automatic control system, and examine them by computer simulation. As an example, by selecting propeller and bow and stern thrusters as manipulated variables and ship speed, lateral shift displacement and heading angle as controlled variables, we herein show that the automatic control system with decoupling control has the ability to react well to wind disturbance.