虚拟手术中模拟软组织切割的混合弹性模型

A Hybrid Elastic Model of Soft Tissue Cutting in Virtual Surgery Simulation

虚拟手术仿真系统应该同时满足真实性和实时性的要求。弹簧质点模型可以满足实时性的要求,但它无法模拟人体的粘弹性特征;而传统的有限元模型虽然可以模拟人体的粘弹性特征,但巨大的时间消耗使得这个方法几乎无法给出实时的反馈。混合弹性模型是一种基于有限元方法的优化模型,由于采用了简化措施,使得它既克服了弹簧质点模型的缺陷;同时也满足了虚拟手术的实时性要求。实验证明混合弹性模型在虚拟手术的真实性和实时性之间达到了一个较好的折中效果,它可以实时的提供视觉反馈,同时也使在虚拟手术系统中引入力反馈器成为可能。

The virtual surgery simulation system must meet 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 property. 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 amount of computation. The hybrid elastic model is an optimization model based on the finite element method. Using simplifications it not only can overcome the demerit of spring - mass model, but can meet the real - time requirement. The result of experiment has shown a good compromise between the two demands. The model can output the vision feedback and even makes it possible to introduce the force feedback device into the virtual surgery simulation.