| The research and development of navigation simulator is the subject to which the international maritime industries generally pay close attention in recent 20 years. In recent years, with the rapid development of computer technology, information engineering and automation technology, etc., the computer simulation technology, especially virtual reality technology, has gotten rapid development. Navigation simulator, as navigation education equipment for the computer simulation from the 1970s, is in a new stage in kind, function and technical feature.The visual scene system is an important part of the navigation simulator, influencing the whole fidelity of the navigation simulation system and the training result of ship handling. The lifelike visual scene environment can make the maneuvering person feel on the spot. The visual scene database modeling is the key and foundation of the research on visual scene system and also one of composition parts of the subject of "research on the visual scene system of Multi-mission navigation simulator" of Shanghai Maritime University.Chapter one of this paper has mainly expounded the current development of the visual scene system of navigation simulator, pointed out the goal and realistic meaning of the research, and at last put forward the main researching content, train of thought and method used in the paper.Chapter two has introduced the current development of main technologies involved in the visual scene modeling of navigation simulator. It includes the computer figure technology, software development approach facing the target, developing technology ofvisualization, and visual scene simulation technology, etc.. These technologies offer the theoretical foundation for the research in this paper.Chapter three has mainly introduced the outstanding three-dimensional modeling and presenting software of MultiGen and Vega in the field of visual scene simulation, for the visual scene simulation of navigation simulator needs powerful simulation software to be supported. It has introduced the modeling technology of MultiGen in detail, the formation of MultiGen system, the structure of OpenFlight and the key technology used in MultiGen, and the formation situation of Vega.Chapter four has made a concrete research on the modeling technology in the visual scene system of navigation simulator. It has introduced the commonly used coordinates system in scene modeling and some different technologies which are used in the interactive procedure, including the modeling technologies based on geometry and physics information, which shows the model by simple lines and complicated curved surface and puts it on the proper position in the scene with three-dimensional geometry variation technology at last after setting up models.Chapter five is the focal point of the full paper. It has explained in detail the whole modeling flow and producing method of the visual scene database of navigation simulator. It is started with the specification requirement for the visual scene data base by navigation simulator, and adopts three-dimensional data structures to construct the visual scene data base model of navigation simulator. In the course of practical research, it has summarized out the rational visual scene data base modeling flow, and put forward the three-dimensional real sense topographical modeling method based on simple electronic sea chart contour information and three-dimensional object producing method, including three-dimensional building on the bank, assisting navigation marks, foundations of shipping model and the processing method of light quality data. At last, it has introduced the issues which should be noticed when the whole visual scene database is formed and debug.The conclusion part has summed up the research content of the subject and put forward the further imagination and expectation on the research work in the future.The modeling method of visual database put forward in this paper has already been popularized and applied in the projects...
|
PDF Full Text Request