Study On Control Method Of Latitudinal Movement Of Ship On The Basis Of Periodogram Modeling

The shorted prediction for and control the movement cross direction of shipping is very essential to the safe catapulting and the efficient navigate and curb of the vessel. Because of the action of the ocean wave, wind and the other interactions, the shipping has complex movement in six degrees that is of a very strong random property. So, it is very difficult for us to predict and control the movement attitude of the shipping in a very short period and it needs further study whether in theory or real project.On the basis of analyzing and comparing the history and the present study condition in foreign and China for the motion prediction and control of shipping, at first this paper establishes the latitudinal equations of the shipping, analyzes the wave-exciting force of the shipping in details in a seaway and presents the formulas of heave force and pitch torque. On the basis of that, the latitudinal attitudes of the shipping are estimated by using Kalrnan filtering. Then, the stochastic optimal control schemes of the latitudinal attitudes are also studied. Furthermore, we study the periodogram predictor and controller seriously ,using experimental data to predict and control the shipping motion. Periodogram as a new predictor and controller is rarely and become more and more being at a premium overseas and inland. As compared with optima] control, periodogram predictor is rather meet the case of large-scale nonlinear system, optimal control is rather meet the case of smallness linear system.The investigation and simulation results show that the two methods are effective and practicable on predicting for and controlling the movement cross direction of shipping: periodogram predictor and controller is super than optimal predictor andcontroller in the case of large-scale nonlinear system.