Modeling Deformable Objects for Medical Training with Haptic Devices

Medical training systems often require the use of haptic interaction with deformable models and high visual fidelity. It is necessary to get a compromise between the geometric model and the deformation model in order to achieve the required frame rate for haptic interaction of 1000Hz. Frequently low level geometric models are used to describe the geometry of the object. This produces large data structures for which it is difficult to reach real-time force feedback.This paper proposes to use a novel model based on Bezier hyperpatches to represent the object, computing the deformation using a mass-spring system. This model can represent free form objects in a concise way. A small test application to simulate palpation with a haptic probe is presented.