Haptic rendering of complex deformations through handle-space force linearization

The force-update-rate requirements of transparent rendering of virtual environments are in conflict with the computational cost required for computing complex interactions between deforming objects. In this paper we introduce a novel method for satisfying high force update rates with deformable objects, yet retaining the visual quality of complex deformations and interactions. The objects that are haptically manipulated may have many degrees of freedom, but haptic interaction is often implemented in practice through low-dimensional force-feedback devices. We exploit the low-dimensional domain of the interaction for devising a novel linear approximation of interaction forces that can be efficiently evaluated at force-update rates. Moreover, our linearized force model is time-implicit, which implies that it accounts for contact constraints and the internal dynamics of deforming objects. In this paper we show examples of haptic interaction in complex situations such as large deformations, collision between deformable objects (with friction), or even self-collision.