Virtual Adhesive: a Way to Handle Sticky Collisions in Surgical and Biological Simulators

Abstract

A variety of methods have been proposed to efficiently process collisions between deformable objects. The method presented in this paper allows to model sticky states between deformable objects with triangulated surfaces. In contrast to an often used approach that consists of generating forces which eventually separate colliding objects, our method is based on the creation of an adhesive virtual object (virtual adhesive). This virtual adhesive is composed by "clones" of all particles locally in collision. Particle clones are used to gather forces on the virtual adhesive, which behaves like a rigid body. The resulting displacement of the virtual adhesive is used in turn to constrain the particles displacement: particles stick to their clone. As a result, no further interpenetration is possible and a sticky state is obtained in the considered zone. Moreover, the method correctly resolves contacts without introducing additional energy in the system. Results are presented through several simulations.