A Hybrid Elastic Model Allowing Real-Time Cutting In Virtual Surgery Simulation

The virtual surgery simulation system must fulfill the demands of the reality and the real-time. The spring-mass model meets the real-time requirement, but it can not reflect the elastic character. Although the traditional finite element method can solve the realistic problem very well, it can not output the real-time feedback due to its huge cost of computation.The hybrid elastic model is an optimization model basing on the finite element method and it is composed of a static part and a dynamic part. The former one just only supports the deformation and the latter one allows deformation and cutting. The model not only can overcome the demerit of spring-mass model, but can fulfill the real-time requirement. The result of experiment has shown a good compromise between the two demands. The model can output the real-time vision feedback and even can make it is possible to introduce the force feedback device into the virtual surgery simulation.This paper has mainly discussed the following contents:(1) Construct the hybrid model.Construct the static part and the dynamic part of the hybrid model separately. Force and displacement can be exchanged by the connecting vertices. Make out the connection vertices of the two groups of hybrid model and make the connection files separately. For the purpose of getting a better experimental result to be compared, we construct two groups of hybrid model using two different methods.(2)Edit the simulation program which can be divided into the following parts: the basic deformable module, the main simulation module, the collision module and the rendering module.(3)We analyze and compare the experimental data of the two groups of simulation in detail. We point out the steps to improve the experiment in future and make a prospect about the development of virtual surgery simulation.