The method for automatic control of a ship with directional instability

Abstract A method for creating an automatic control system for a ship with directional instability has been developed. As part of the tests of a small-sized unmanned vessel, a control diagram was built. It showed that the vessel is unstable along its route. It became necessary to add a control channel for the angular acceleration of the vessel to the main channels of the PID regulator. The PID-U regulator has a significant advantage in controlling an unstable vessel on the route over a standard PID regulator due to the channel of angular acceleration; the regulator monitors the angular speed and compensates it with control actions. The disadvantage of the method is difficulties in finding the angular acceleration of the vessel, since, gyroscopic sensors installed on vessels provide data only on the route and angular speed. Simple integration of the angular speed to determine the acceleration can result in errors, especially in wind-wave conditions. The mathematical observer based on the Kalman filter can be used. The results of operation modeling forthis regulator are described.