Synchronous-ballistic control for a twin-rudder ship
船舶双舵同步补偿控制

In a ship with twin-rudder, the structure parameters and electrical parameters are different in two steering gear systems. During the navigation, the error between the angles of the twin-rudder will be increased; and the efficiency of rudder power and ship maneuverability will be reduced. To reduce the error between the angles, we propose a synchronousballistic control approach based on fuzzy logic with variable universe. Firstly, the theoretical model of steering gear system is constructed. Secondly, the structure of the synchronous-ballistic control system of twin-rudder is developed based on the master-slave control strategy. Thirdly, fuzzy logic with variable universe theory is introduced to improve the adaptability of PID; thus the variable universe adaptive fuzzy PID synchronous-ballistic controller is designed. Finally, the simulation results show that the error between angles of the twin-rudder can be effectively reduced and the stability is automatically improved by the designed controller. This method is valid and reliable for synchronizing control of twin-rudder and is significant for engineering application.