Research And Application On Collision Detection Method Of Secondary Objectthe Simulation

In trampoline sports simulation, human body, which is the main object, is self-active, so the simulation of body sports must be achieved firstly. But in order to have a vivid feeling and implement a system possessing the property of strong immersion, we must also simulate the non self-active secondary object of the trampoline. After adopting the human body sports tracing method for achieving the human body sports simulation based on the instantial data, we don't need to consider the influence of the secondary object of the trampoline on the human body sports. The thesis puts emphasis on the simulation method of the secondary object and achieves the following accomplishments:1) Non-physical simulation method of trampolineWe can adopt two kinds of method on the secondary objectssuch as the trampolines. One is the physical simulation and- the other the non-physical simulation method. These two kinds of method all could describe the basic properties of the secondary objects. The difference lies in that the physical simulation sees the whole trampoline as spring-particle model and the non-physical simulation sees the whole trampoline as particle-grid model. Because in the trampoline simulation we couldn't confirm the elasticity coefficient, the amount and direction of the force, the physical" mode is correlative with the experience. And in order for satisfying witrt the demands of real time and stability, the physical-mode needs to decrease the number of the particles and increase the time step, but in order, to enhance the system immersion ,we must do the opposite way. This is the limitation in the physical simulation arithmetic, so it is not adapted to the trampoline imitation. In contrary, there is no need for the non-physical mode to confirm the elasticity coefficient and judge the amount and direction of the force put on the trampoline by the human body, and it is not sensitive to the number of the particle and the time step. An question of the non-physical mode is that it couldn't feed back the force to the human body, but because-the adopted data is the captured true data , whether or not feedback couldn't change thehuman body sports, it is not necessary to obtain the feedback force on the human body through the physical mode. The non-physical simulation mode on the base of the human body simulation based on the sports instantial data can get an excellent simulation results, and fit into the demands of the immersion, stability and real time of the system.2) Simulation of the secondary objects based on the collision detection and the application of sports instantial data.Due to the true, reliable data of the human body through adopting the sports capturing method, we can correctly reflect the motion after the interaction of the sportsman and the trampoline under the actual simulation. We can make full use of the instantial data to implement the trampoline simulation. In order to simulate the trampoline, we must obtain the touching point of the sportsman and the trampoline. So it is necessary to judge the sportsman's gesture at the touching point. Because of the advantage of conveniently constructing and simply intersecting judgment, we adopt the AABB bounding box method for the intersecting judgment. After adopting the AABB bounding box ,our system can satisfy with our system's demand of real time.3) The correlative implemented research in VHTrampolineVHTrampoline is the expert item<>[2001BA904B08] supported by the Olympic science and technology, and is the assistant training system of the trampoline sports developed by ICT. The thesis is going on the base of the VHTrampoline, and apply the achievements to the VHTrampoline system.