Parameter Identification And Motion Prediction Of Nonlinear Motion Model Of Ship

The identification and prediction of nonlinear motion model parameters is an important part of ship research.Good motion forecasting not only plays an important role in the safety and control of ships,but also provides assistance in the accuracy of missile launch.The prediction of ship motion can not only provide help for the safety of the carrier,but also provide the data base for the research of ship's seakeeping.The following research is carried out.Is the study of ship motion model of the nonlinear ship motion mathematical model parameter identification and forecast the basis and key to establish accurate mathematical model for ship motion and the simulation can better research the movement characteristics and wave resistance of the ship.In the mathematical model of ship motion,the separation model(MMG)not only has practical physical significance,but also can study the hydrodynamic parameters of ship's fin and rudder.Therefore,this paper adopts the idea of the separation model to study the establishment of mathematical model of ship motion.Detail type separation model of each component,the moment in the constitution and the derivation and calculation method of hydrodynamic coefficient,analyzed the characteristics of the waves and waves of ship motion disturbance,eventually waves under the interference of nonlinear ship motion mathematical model is set up and the ship motion simulation.In the process of establishing the mathematical model of ship motion,the calculation model parameters are complicated and the deviation is large.This paper studies the identification modeling method and proposes an extended Kalman filter algorithm to identify the nonlinear model parameters of the ship motion.To separate type model combined with extended Kalman filter algorithm,using extended Kalman filtering algorithm separated type identification of model parameters of the mathematical model of ship motion,through the simulation experiment data,the analysis model parameter identification curve,verified the identification results.Finally extended Kalman filtering algorithm,the online adaptive identification model of ship motion parameters,forecast model is set up,and ship motion prediction,by analyzing the results of the experiment,the forecast effect is better than the AR prediction method based on Kalman prediction algorithm and based on the recursive least squares algorithm of AR prediction method,forecast accuracy is higher.