The Prediction Of Ship Maneuverability And Virtual Scene Simulation

Maneuverability is one of the most important performances of navigation, which has a great influence on ship's transport safety. In order to improve ship safety of navigation, reduce or even avoid the marine environmental pollution caused by shipwreck and ensure the ships having good maneuverability, the prediction of maneuverability is very important. Warships with good maneuverability can move flexibly, occupy the favorable position, carry forward the firepower to attack the enemy and avoid enemies'attacks in the battle.At present there are three ways of the prediction of maneuverability, such as freedom to self-ship model testing methods, empirical estimating methods and the computer simulation based on mathematical models. The technology of visual simulation can reduce the trial and study time, but also improve the quality of testing and development, as well as saving the development funding.The maneuverability of the ship was studied based on MMG handling equations of motion in this thesis, using the visual simulation. The convenient interface of the operation was compiled to simulate the ship real-timely. The main topics of this thesis are as follows.First of all, based on the ideas of MMG separate model, a variety of hull hydrodynamic forces were analyzed simply and estimated considering the heel. The wind and wave forces as the external part were stacked to the separated mathematical model of ship motion, and eventually four-degree freedom mathematical model was established in the wind and wave environment.Secondly, the maneuverability of ship was simulated in the still water, including the numerical simulation of turning test and zigzag test. Compared with the experimental data, this mathematical model was true. In the wind, the ship appeared drift trajectory reverse the wind direction. Similar to wind interference, the ship appeared drift trajectory in the wave, and the initial wave angle impacts on the trajectory obviously.Then, the three-dimensional large ship model was created by Creator. Key technologies such as LOD, Instance, Billboard and so on, were used to simply the model in order to get the realistic and efficient three-dimensional model. By the use of Vega motion simulation environment was set up and Adf file was defined. Finally, according to the theoretical prediction of ship maneuverability, the structure of kinetic control system was established. The visual simulation of the maneuverability was described by Vega, using the frame of MFC. Consequently, it is convenient to operate the simulation. In a word, the results of this thesis can provide the reference of the seamenwhile handling the ships in practice. Further more, this thesis lays a foundation in researching the maneuverability of large ship using the simulating mean.