Geometric modeling and collision detection based on hybrid bounding box in virtual gallbladder surgery

With the virtual surgery simulation system playing an increasing role in the medical filed, a method of reconstructing a virtual gallbladder geometric model and an algorithm of collision detection based on S-AABB hybrid bounding box in virtual gallbladder surgery are put forward. In the process of geometric modeling, we can compile program to read and store the information of contour vertexes and triangle facets, and index the position of triangle facet vertexes in vertex array, so that triangle facet is correlated with vertex array. Because the program only need to call the vertex information in the simulation, it will reduce the time consumption. To avoid traversing every triangle facet of operation object in collision detection, we create a list which includes its all adjacent triangle facets. When a triangle facet is collided, we just judge that whether its adjacent ones are collided or not, not traversing all ones. This method must optimize the algorithm of collision detection and improve the real-time and accuracy of virtual surgery system.