Study On Control Method Of Rudder Anti-pitching For Ship

Stabilization is one of the important subjects for the ship and ocean engineering. According to the research situation both at home and abroad, the technology of rolling stabilization is becoming riper and moving toward perfection step by step. But, the problem of pitching stabilization has not gotten very good settlement. It is significant for the getting up and dropping of the ship-board aircraft, habitability and seagoing performance of ship that a effective method of anti-pitching can be found.In this paper, a kind of rudder is used as the equipment of anti-pitching through the analysis of relevant research state both at home and abroad. Firstly, the ship longitudinal motion equation of two freedom degrees on the basis of the strip theory. Secondly, the least square method by recursion is carried on modeling for the disturbing force and moment of random sea. Thirdly, the classic stochastic optimal control and the extended stochastic optimal control are studied by contrast in the effect of anti-pitching, in addition, the analysis for the classic Kalman filtering and the extended Kalman filtering is included. Finally, the algorithm of predictive control based on state space is studied by introducing the generalized predictive control into the research of anti-pitching for ship.Through the theoretical analysis and a large amount of simulation results, It can be shown that the classic stochastic optimal control is goodish for rudder anti-pitching, but, the extended stochastic optimal control and the generalized predictive control can get comparatively satisfied results.