Study On Ship Steering Control System Simulation Based On VV&A

In order to solve the problem that the simulation credibility is low in the field of ship steering control system simulation,this dissertation applies VV&A technique of modeling and simulation to the ship steering control system simulation to enhance the simulation credibility. The systematic and thorough investigation on ship steering control system simulation based on VV&A is completed.The main achievements are included as follows;(1)Modeling is the basis of simulation,and most of VV&A activities are concerned with modeling.At first,several ship motion mathematical models are established,including MMG, Nomoto and Norrbin models.And the characteristics of wind,wave and flow disturbances are discussed.Based on the practical parameters of 5446 TEU container ship "Shanghai", different mathematical models are established.The models are verified via turning simulation calculation compared with the data from the trial voyage conditions.And simulation results of relevant models are compared to analyze the relationship between the models.(2)VV&A of Modeling and simulation is used to analyze and ensure the credibility.The basic conception,principle,method and process of VV&A are discussed.And then some methods and principle are used to analyze the problems in the ship steering control system simulation,such as selection of models,affection of model intactness and exactness.At last, based on one VV&A process,the VV&A process of ship steering control system simulation is completed.(3)Based on the VV&A process of ship steering control system and virtual reality technique,the virtual distributed simulation system for ship steering control algorithm testing is set up.The system is helpful to ensure the credibility of simulation test of ship steering control algorithm.It is convenient for user to observe the process of the online simulation through the display of virtual distributed simulation.And it is useful to improve the algorithm and accelerate the application of the control theory to the marine and ocean engineering.(4)A predictive control algorithm based on RBF neural network is adopted to the ship steering control.And the corresponding algorithms are tested via VV&A process.Recursive k-means clustering algorithm and recursive least squares algorithm are used to adjust the RBF neural network.And clonal selection algorithm is used in predictive control algorithm to ensure the global optimal solution.Based on the established algorithm testing system,the algorithm is tested.The simulation process added with VV&A activities obviously enhances the credibility of the simulation.And the simulation results show that the predictive control algorithm based on RBF neural network possesses good control performance and strong robustness.