Fuzzy Adaptive Sliding Mode Control For Ship Fin Stabilizer System And Dynamic Simulation Research

The seaworthiness and safety of the ship will be severely affected by the roll motion when the ship is sailing on the sea under conditions of disturbances such as wind,wave and so on.Fin stabilizer is the most effective anti-rolling device and it has been used widely so far.This paper aims at studying fuzzy adaptive sliding mode control for fin stabilizer system based on the nonlinear mathematical model of ship roll motion.In addition,the paper has completed the dynamic simulation study on the operating interfaces of fin stabilizer control system and the working process of the hydraulic system by referring to a real ship.The main research contents of the paper include the following parts:(1)The mathematical model of random sea wave of the long-crested wave is established based on the spectral density analysis theory of random sea wave.And series of numerical simulations of the random sea wave are carried out according to the equal energy method with various sea conditions.(2)The nonlinear mathematical model of ship roll motion is established considering the characteristic of the nonlinearity of ship roll motion under high sea condition.And the simulation results under different sea conditions verify the validity of modeling ship roll motion based on the parameters of a ship.(3)First,considering the nonlinearity and uncertainty of ship roll motion,the sliding mode controller is designed for fin stabilizer control system and simulations are carried out.Then,on account of the characteristic of strong dependence on the mathematical model of ship roll motion when designing the sliding mode controller,and combining the properties of excellent approximation of fuzzy adaptive control and insensitive to disturbance as well as the object's variable parameters of sliding mode control,the fuzzy adaptive sliding mode controller is designed for fin stabilizer system which is independent of the mathematical model of the object.Finally,simulations of ship roll motion are carried out based on the design under different sea conditions,and the results show that the designed controller has good robustness,adaptability,and effective anti-rolling efficiency.(4)Based on DMS marine engine room simulator simulation platform,and referring to the central control unit and bridge control unit as well as the structure diagram of hydraulic system of the training ship "Yu Kun" of Dalian Maritime University,the paper develops the dynamic simulation of the operation interfaces and the hydraulic working process of fin stabilizer system which have friendly human-computer function.