Adaptive fuzzy sliding mode controller design for ship fin stabilizer under rough sea conditions

Considering the nonlinearity, parameters perturbation and random waves disturbance to the ship fin stabilizer system during ship sailing on the rough sea, a robust controller based on sliding mode control which incorporates fuzzy tuning technique is proposed in this paper. The sliding mode control is used to force the ship roll to zero. The fuzzy tuning is adopted to eliminate the chattering of control input. The system stability is analyzed by using the Lyapunov theory. Simulation results show that the method is effective to decrease ship roll motion in rough sea conditions, and when the speed and initial metacentric height of ship change, high anti-rolling efficiency is still maintained, which prove that the control strategy presented in this paper has strong robustness.