虚拟装配中基于公差约束的碰撞检测方法研究

Research on Tolerance Constraint-based Collision Detection Method in Virtual Assembly

为了更好的仿真零部件的装配过程,给出了一种基于公差约束的碰撞检测方法及响应策略:首先给出了虚拟零部件的层次模型表达构建方法;其次提出了基于体分解的空间层次包围体表达方法,给出了压缩包围体冗余空间的算法;再次给出碰撞穿透深度的计算方法,通过比对最大穿透深度值与零部件间公差范围,产生不同的碰撞响应策略;第四以孔-轴装配为例,给出了虚拟空间中未受约束与受约束零部件的装配方程;最后通过仿真给出了孔-轴零部件之间的装配过程。实验结果表明,在装配的碰撞检测过程中引入公差约束信息,可以增进装配仿真的真实感,提高装配效率。

For simulating the assembly process of the component and part better, the collision detection method and response strategy based on tolerance constraint were proposed. Firstly, the construction method of the virtual component hierarchical expression was illustrated. Secondly, the expression method of the space hierarchical bounding volume based on the volume decomposition was proposed and redundant space compressing algorithm of the bounding volume was demonstrated. Thirdly, the method of calculating collision penetration depth was provided and according to comparing the maximum penetration depth value with the tolerance range of the part, different collision response strategies were obtained. Fourthly, as the hole-axis assembly an example, the assembly equation of the unconstraint part and constraint one in virtual environment was expressed. Finally, the assembly process of the hole-axis was shown by simulation. The simulation result indicates that it could increase the sense of reality and enhance the efficiency of the assembly by introducing the tolerance information into the collision detection in virtual assembly.