Research Of Collision Detection Algorithm In Microscopic Traffic Simulation

Collision detection problem has being one of the most concentrating studies in virtual reality, visual simulation and other fields. Hence, the accurate collision detection is significantly crucial to enhance the authenticity of the virtual environment and the immersion of virtual environment; while the complexity and real-time attribute in virtual environment require an advanced demand for collision detection.This dissertation did the following researches based on the Scientific and technological projects in Chengdu-"Study in passenger transport driving simulation system for traffic safety". First of all, studied various collision detection algorithms widely applied at present, and analyzed two typical algorithms: space partition method and bounding box method, and summed up their merits and applied conditions respectively. Secondly, the main structure of Open Scene Graph (OSG) and Open Dynamic Engine (ODE) are analyzed and focus on the extraction of OSG model data to construct the corresponding ODE geometry model of the collision, and summed up the combining approach. Thirdly, focusing on the characteristics of microscopic traffic simulation environment, in which three-dimensional scene is in high precision, complex scenes, and containing a huge number of the dynamic objects and geometric features, this dissertation applied the scene rendering mechanism and the collision detection separated mechanism, and realized management of scene rendering by OSG, as for collision detection among scene models, this dissertation constructed the corresponding ODE Collision geometry objects in order to apply collision detection engine in ODE to realize the collision detection and simple response among objects. Such result from division of labor is to make sure the fluent scene operation, the accurate collision detection, and to realize the base collision response.In conclusion, the collision detection approach proposed in this dissertation can obviously enhance the accuracy of collision detection among complex objects, and acquire faster speed of collision detection. Also, this project is easily to extend and decrease the cost of software significantly, since the realization of approach was insisted on the basement of open source development packages. In addition, the approach realized the collision detection through the combination between OSG and ODE to establish physical model, is not only appropriates in the development of transport driving simulation system, but also of robot simulation, simulated battle field and such military simulation system.