Rudder roll stabilization

This paper discusses the possibilities for roll stabilisation of a ship by means of the rudder. It presents mathematical models for the ship's dynamics, the disturbances, e.g. waves, and the steering machine. A design procedure for a combined controller for roll and yaw is presented. Special emphasis is placed on the effects of the limited rudder speed because this appears to be one of the design parameters which determines the possible success of a rudder-roll- stabilisation system. Results of simulation are included, as well as plans for full-scale trials and scale-model tests in the near future.