An international conference connecting people
in CAD research, education and business
Bookmark and Share
Copyright (C) CAD Solutions, LLC. All rights reserved.
Proceedings of CAD'17, 2017, 191-195
Fast and Accurate Local Minimal Distance Computation between Industrial CAD Models for Interactive Dynamics Simulations

Sébastien Crozet, Xavier Merlhiot, CEA, LIST, Interactive Simulation Laboratory, Gif-sur-Yvette
Jean-Claude Léon, INRIA, Grenoble University

Abstract. Computing contact points between two CAD models is important for many applications including motion-planning, physical simulation, haptic rendering, and robotics. Penetration depth and distance computation are the two main approaches for defining and computing contact points. The method described on this paper is distance-based and produces results (contact points and contact normals) that evolve continuously with respect to motion parameters. Such continuity is desirable in the context of interactive physical simulation of scenarios involving rolling and sliding motions where jumps in the normals directions may induce numerical artifacts that affect the behavior of the simulated objects. We achieve this by working directly with the smooth representation of the CAD models instead of resorting to a tessellation. Alternative methods based on the computation of a continuous penetration depth exist but only consider an approximation of the contact space, and are limited to translational motions only. The main contributions of this paper are a complete method for computing contact points between CAD models without tessellation, an off-line geometrical analysis for grouping several exact distance computations into a single one, and a new bounding volume for normals which is much tighter than existing alternatives.

Keywords. Collision Detection, BRep, Smooth Constraints, Interactive Simulation

DOI: 10.14733/cadconfP.2017.191-195