| Aero simulator is a large-scale comprehensive system integrated with many technologies. The most important embodiment of the system is scene simulation. In the process of research and development of the first large flight simulator for task training system in China, the architecture and the scene simulating system of aero simulator are projected, and the correlated key technologies are explored and the technical puzzles are solved. The project is completed and passed the assessment of the expertise. It is used for pilot training and gained a good reputation. The main work and innovations are summarized as follows: First, the concept of simulator engine based on HLA architecture is presented and the sophisticated technical design including system software and hardware featured is presented. For the physical designed simulator architecture, the multi-fighter confrontment is emphasized. Based on above conditions and according to the requirement of the aero simulator, the scene simulating system is designed to be a global screen projective system. The system has six channels, it is 180°in horizontal and 130。 in vertical. To author's knowledge, it is the first time to realize the angle of 90°in upright direction under horizontal in multi-channel projective system in the country. Second, the key technologies about global screen projective system are studied deeply. One is nonlinear distortion correction. Based on space transform of graphics, nonlinear distortion equations under the circumstance of mounting projector in spherical center and off-axis are deduced, and pre-distortion algorithm of spherical nonlinear distortion correction is put forward when projectors are mounted in off-axis. The real-time characteristic and validity of the algorithm are proved by experimental results as well as engineering practice. The other is that, multi-eyepoint nonlinear distortion correction of spherical projection is analyzed specifically and nonlinear correction method is found, that settles very important technical problems of multi-eyepoint scene simulation. The method has significant sense in the aspect of scene simulation of multiple trainees, multiple viewpoints, etc. Last, the solution of edge blending of projecting images on six-channel is given. Third, an in-depth study on modeling technique of 3D virtual battlefield is carried out in synthetic simulation system for flight training. Primary content includes terrain modeling, which is especially used for large-scale terrain. The data source analog arithmetic based on large-scale terrain modeling is put forward. At the same time, interpolation algorithm of terrain reconstruction based on bicubic B-spline and fractal is also discussed. An improved algorithm of random midpoint displacement method based on surface fractal character is proposed. By computing fractal characteristic parameters in correlated direction, random midpoint displacement algorithm is modified and the disadvantage of terrain isotropy generated by adopting general fractal methods is overcome, therefore, real simulation effect reflecting terrain aeolotropism is achieved, which the pivotal problem of contradiction between terrain scene calling and terrain modeling is solved effectively. Finally, some key technologies of virtual battlefield environment are studied based on scene simulating system. The first is collision detection in virtual battlefield environment. According to the character of virtual battlefield environment, a collision detection algorithm of interested area based on OBB method is given, which can greatly improve availability of collision detection without reducing the accuracy of collision detection and without increasing computation load. The second is the implementation of environmental special effect based on particle system. In the light of basic principle of particle system, fiery, models of rain, snow, etc for virtual battlefield environment is established and optimal effect is obtained. The result well meets the needs of the simulation in virtual battlefield.
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