Abstract: Bounding boxes hierarchy is an important technology of collision detection，it can enhance precision and reduce the complexity of calculation.First，the paper introduces the method to compute OBB，the theory of OBB intersect test，and the common process for the construction of OBB bounding boxes hierarchy.Combining the hierarchy of model，proposes a constructed method of OBB bounding boxes hierarchy based model hierarchy.The test show that the improved method speed up updating speed of OBB tree when modules of model moved，made OBB method to fit for the case that mode is made of rigid bodies.

Key words: OBB, hierarchy bounding boxes, separation axis

摘要： 层次包围盒是碰撞检测的重要技术，可以提高碰撞检测精度并减少碰撞检测复杂度。首先介绍了OBB包围盒的计算方法、相交测试原理，以及OBB层次包围盒构造的一般过程。结合物体模型的层次结构，提出了基于模型层次结构的OBB层次包围盒的构造方法。实验结果证明改进后的方法加快了模块之间可以发生变化时其对应的OBB树的更新速度，使OBB方法适合由刚体模块构成的模型变形的情况。

关键词: OBB, 层次包围盒, 分离轴