Research On Collision Detection Of Soft Tissue In Virtual Surgery System

In recent years, virtual surgery system is concerned by more and more people and leads agrowing number of scholars to do some research work about it. There have a lot of technicalpoints in the system. Soft tissue of Collision detection is one of the key parts which directlyaffects interactive and real-time of the system.Currently, there have a lot of methods for collision detection of the soft tissue, amongwhich the hierarchical bounding box method is very effective. It uses the bounding box toinstead of the geometric model of the real objects in collision detection which is similar to thegeometric model in size, shape and has simple geometric characteristics. In the course, ahierarchical structure is formed by the bounding box depending on a certain algorithm. Wecan quickly exclude the regions which are not intersected and get accurate results on onlydealing with primitive pairs whose bounding volume is intersected.In this paper, we designed an improved axial bounding box collision detection algorithmfor virtual surgery training platform. The main work of the paper is shown as follows:Firstly, proper hierarchical bounding box was first selected by comparing the tightness,update rate, time consuming and degree of maturity of common bounding box.Secondly, the traditional method of triangle detection was improved, which furtherimproved the rate of collision detection, ensured the interactivity and real-time of the systemand enhanced the immersion for virtual environment.Thirdly, a new algorithm for bounding box update was proposed based on the differencebetween collision detection with flexible object and rigid body. All technical details of virtualsurgery training platform were concerned in this algorithm to solve the problem about slowupdating rate of bounding box.Finally, the vtk was imported to realize all the above ideas which is3D graphics libraryand applied more and more widely. Test results showed that the method perfectly fit virtualsurgery training platform.Above all, the algorithm in this paper improves the updating rate of bounding box after software tissue deformation and improves the method of collision detection of triangle inthree dimensional space, which greatly improved real time of the whole system. Test resultsshowed that this algorithm has an advantage in speed over the former one and can get moreprecise information for collision detection.