Voxel-based haptic rendering using adaptive sampling of a local distance map

Abstract

Change of shape is an essential topic in research related to virtual reality-based sculpting, mechanical machining, and surgery training of tissue cutting. If the shape of an object in the virtual environment is modified at high temporal rates, it is very difficult to resolve contacts between objects due to the fact that the existing haptic rendering algorithm depends on expensive preprocessing strategies such as bounding volumes, bounding volume hierarchies, and distance fields. This paper investigates a haptic rendering algorithm in virtual environments with shape changes. We introduce a volumetric collision model and an on-the-fly contact normal computation method with a local distance map, which allow for shape changes of the volume model at time-critical haptic rendering. This approach significantly reduces the voxel readout, which allows the model to handle more than ten thousand voxels at haptic rates. The real-time tooth probing and cutting simulation results support the benefits of our approach.