基于SPH方法的流体粒子与软体碰撞检测

针对虚拟手术系统中流血粒子与软组织器官碰撞检测的问题进行了研究.虚拟手术中流血与软体器官组织进行碰撞检测不同于传统的刚体或者软体之间的碰撞检测,流血模型的拓扑结构变化较大,传统方法通过更新拓扑结构来进行碰撞检测的方法不能够保证碰撞检测的实时性和准确性.提出一种基于空间划分的流血粒子与软体碰撞检测算法,能够处理基于光滑粒子流体动力学(Smoothed Particle Hydrodynamics, SPH)模拟的流体与任意动力学模型模拟的软体之间的碰撞检测.同时,提出了对SPH算法进行最近相邻粒子搜索过程中建立起的均匀空间网格进行重复利用,使空间网格用于碰撞检测的空间划分与流体粒子的定位,从而减少了时间和空间资源的重复消耗.实验结果表明,该算法能够满足虚拟手术中流血粒子与软体之间的碰撞检测对精确性和实时性的要求.

SPH Based Collision Detection Between Fluid Particle and Soft-Tissue

In this work, the problem of collision detection of bloody particles and soft tissue organs in virtual surgery system was studied. The problem of collision detection between bloody blood and soft tissue in virtual surgery is different from that of traditional rigid body or software collision detection. The topological structure of bloody model changes greatly. The traditional method of collision detection by updating topology cannot ensure real-time and accuracy. A collision detection algorithm for bloody particles and software based on space partitioning is proposed, which can handle collision detection between software based on Smoothed Particle Hydrodynamics (SPH) simulation and software simulated by any dynamic model. At the same time, the uniform space grid established in the nearest neighboring particle search of SPH algorithm is proposed to be reused. The space grid is used for the space division of collision detection and the localization of fluid particles, thus reducing the time and space resources repeated consumption. Experimental results show that the algorithm can meet the accuracy and real-time requirements of collision detection between bloody particles and software in virtual surgery.