Disturbance Compensation Model Predictive Control for Integrated Rudder/fin Roll Stabilization

Conventionally, the rudder is used to control the heading of the ship and the fin stabilizer is used to reduce rolling. There are interactions between the control effects of rudder and fin stabilizer. Integrated rudder/fin roll stabilization is to make the rudder and the fin stabilizer work collaboratively, to avoids the harmful interference and enhances the performance of roll stabilization. A model predictive control method with disturbance feed-forward compensation mechanism is proposed in this paper. A disturbance observer is adopted to estimate the lumped disturbance consists of model mismatch and external disturbance base on the nominal model, and the control actions were generated by the model predictive controller with the lumped disturbance. Simulation studies show that the controller is flexible to be set and is able to deal with saturation of actuators, the rudder and fin stabilizer are controlled collaboratively and the roll stabilization performance is enhanced without significantly deteriorating the heading control performance.