THE ART TO KEEP IN TOUCH - The “good use” of Lagrange Multipliers

Antoine Jonquet, Olivier Nocent, Yannick Remion

Abstract

Physically-based modeling for computer animation has become a wide spread framework because it allows to produce more realistic motions in less time without requiring the expertise of skilled animators. But, a computer animation is not only a numerical simulation based on classical mechanics since it follows a precise story-line. One common way to define aims in an animation is to add geometric constraints. There are several methods to manage these constraints within a physically-based framework. In this paper, we present an algorithm for constraints handling based on Lagrange multipliers. After few remarks on the equations of motion that we use, we present a first algorithm proposed by Platt. We show with a simple example that this method is not reliable. Our contribution consists in improving this algorithm to provide an efficient and robust method to handle simultaneous and antagonist constraints.

References

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Paper Citation


in Harvard Style

Jonquet A., Nocent O. and Remion Y. (2007). THE ART TO KEEP IN TOUCH - The “good use” of Lagrange Multipliers . In Proceedings of the Second International Conference on Computer Graphics Theory and Applications - Volume 2: GRAPP, ISBN 978-972-8865-72-6, pages 47-54. DOI: 10.5220/0002085000470054


in Bibtex Style

@conference{grapp07,
author={Antoine Jonquet and Olivier Nocent and Yannick Remion},
title={THE ART TO KEEP IN TOUCH - The “good use” of Lagrange Multipliers},
booktitle={Proceedings of the Second International Conference on Computer Graphics Theory and Applications - Volume 2: GRAPP,},
year={2007},
pages={47-54},
publisher={SciTePress},
organization={INSTICC},
doi={10.5220/0002085000470054},
isbn={978-972-8865-72-6},
}


in EndNote Style

TY - CONF
JO - Proceedings of the Second International Conference on Computer Graphics Theory and Applications - Volume 2: GRAPP,
TI - THE ART TO KEEP IN TOUCH - The “good use” of Lagrange Multipliers
SN - 978-972-8865-72-6
AU - Jonquet A.
AU - Nocent O.
AU - Remion Y.
PY - 2007
SP - 47
EP - 54
DO - 10.5220/0002085000470054