For The Driving Simulator Of The Highway Three-dimensional Visual Modeling

Driving simulators are important tools, which are used in the development of automobile, traffic characteristic study on "man-vehicle-environment" and driving training. In recent years, studying and developing driving simulator become a more and more important direction in the world, because it has many remarkable characteristics such as high security, good recurrence and strong exploration.The development of virtual reality and computer simulation technology offers a technological guarantee for researching and developing driving simulator. Utilize driving simulator to process expressway traffic simulation, which must offer the virtual driving environment for driver at first, and then can enable the driver to get true driving feel during the process of handling the automobile. So the visual modeling is most important to road transportation simulation by the driving simulator.The visual modeling system that my laboratory researched and developed independently can real-time and interactively accomplish virtual scene design according as user's needs and research's purposes, and can provides the work pattern under various kinds of climatic conditions. But on the three-dimension scene design of expressway ,especially 3D models such as the tunnel, bridge and topography etc, this visual system has no unified and integrated modeling technology at present, so it is still to perfect and enrich further.To this question, this paper has researched the scene modeling of expressway and the output of there visual data. A special scene modeling software, which is based on the design curve graph and data about the true expressway's horizontal; vertical and cross section alignment, can quickly set up various kinds of 3D models on and around road, and realize some models' parameter design, and output all models' visual data. The paper particularly expounded all structures' modeling technique and process, such as side slope; retaining wall; tunnel; bridge; transportation installations and scenery model, etc, and how to utilize DEM (Digital Elevation Model) to set up terrain model. To the large-scale complicated terrain whose data is enormous, it provides terrain simplification technology. Through setting uptexture lib we can make texture picture mapping upon the models that are established, thus can realize the dynamical display about expressway 3D scene.The demo result indicates that, the scene which is made by utilizing the scene modeling theory and method stated in this document, not only improve the creation efficiency of scene visualization data, meets the driver's demands basically at the vision, obtains a vivid and tridimensional effect at some degree, but also has already applied in the traffic simulation experiments of correlative expressways in Yunnan Province, provides a favorable foundation for the rationality evaluation of road geometry alignment, impact and evaluation of driver's vision behavior and sight distance to the traffic safety in the future.