Fast Collision Detection and Deformation of Soft Tissue in Virtual Surgery

Abstract

In the virtual scene of robot assisted virtual surgery simulation system, the surgical instruments achieve complex motion following the haptic devices and the soft tissue deforms continuously under interaction forces. In order to meet the rapidity of collision detection, an algorithm based on changeable direction hull bounding volume hierarchy is proposed. Strategy of combining surface model with body model is developed for soft tissue deformation. Skeleton sphere model of soft tissue is built. Deformation can be achieved based on mass-spring theory after matching collision information with the skeleton sphere model. The experiments show that the proposed collision detection method implements faster speed compared with fixed direction hull algorithm and soft tissue deforms through combination of collision information with sphere model.