Studies on the Practical Use of Learning Feed-Forward Control System to Ship Manoeuvring Motion (III)

Abstract

In a previous paper, the author showed experimental results of a ship manoeuvring control system using an actual ship, confirming the effectiveness of a learning feed-forward control system (LFFC). The experiments were mainly concerned with the follow-up control of the ship with either the bow thruster or the rudder. However, in experiments on follow-up control with the bow thruster, response had a tendency to oscillate after 8001000 sec. from the start of the experiment.In this paper, the stability conditions of an inverse system in the LFFC are discussed, then actual ship experiments using the bow thruster with the stabilized LFFC's for follow-up control to the desired heading angle and for compensation control for wind disturbance were carried out.The experiments proved that the LFFC's for follow-up control and compensation control can be stabilized by the stabilized inverse system and that control systems with the LFFC's are useful in the manoeuvring motion control of an actual ship.