Interactive simulation of one-dimensional flexible parts

ABSTRACT

Computer simulations play an ever growing role for the development of automotive products. Assembly simulation, as well as many other processes, are used systematically even before the first physical prototype of a vehicle is built in order to check whether particular components can be assembled easily or whether another part is in the way. Usually, this kind of simulation is limited to rigid bodies. However, a vehicle contains a multitude of flexible parts of various types: cables, hoses, carpets, seat surfaces, insulations, weatherstrips... Since most of the problems using these simulations concern one-dimensional components and since an intuitive tool for cable routing is still needed, we have chosen to concentrate on this category, which includes cables, hoses and wiring harnesses.This paper presents an interactive, real-time, numerically stable and physically accurate simulation tool for one-dimensional components. The modeling of bending and torsion follows the Cosserat model and is implemented with a generalized spring-mass system with a mixed coordinate system which features usual space coordinates for the positions of the points and quaternions for the orientation of the segments joining them. This structure allows us to formulate the springs based on the coordinates that are most appropriate for each type of interaction and leads to a banded system that is then solved iteratively with an energy minimizing algorithm.

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INDEX TERMS

Primary Classification:
  I. Computing Methodologies
  I.6 SIMULATION AND MODELING
      I.6.5 Model Development

Keywords:
cable simulation, cosserat model, modelling of torsion