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Constraints methods for flexible models

Platt, John C. and Barr, Alan H. (1988) Constraints methods for flexible models. ACM SIGGRAPH Computer Graphics, 22 (4). pp. 279-288. ISSN 0097-8930. doi:10.1145/378456.378524.

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Simulating flexible models can create aesthetic motion for computer animation. Animators can control these motions through the use of constraints on the physical behavior of the models. This paper shows how to use mathematical constraint methods based on physics and on optimization theory to create controlled, realistic animation of physically-based flexible models. Two types of constraints are presented in this paper: reaction constraints (RCs) and augrmented Lagrangian constraints (ALCs). RCs allow the fast computation of collisions of flexible models with polygonal models. In addition, RCs allow flexible models to be pushed and pulled under the control of an animator. ALCs create animation effects such as volume-preserving squashing and the molding of taffy-like substances. ALCs are compatible with RCs. In this paper, we describe how to apply these constraint methods to a flexible model that uses finite elements.

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Additional Information:© 1988 ACM. We wish to thank Jed Lengyel for rest state models and John Snyder for rendering software. This paper was supported by grants from Apple Computer, Hewlett-Packard Company, Symbolics Inc., and an AT&T Bell Labs Fellowship.
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Hewlett-Packard CompanyUNSPECIFIED
Subject Keywords:Elasticity, Modeling, Dynamics, Constraints, Simulation
Issue or Number:4
Classification Code:G.1.6 -- Constrained Optimization; 1.3.7--Three-Dimensional Graphics and Realism (Animation)
Record Number:CaltechAUTHORS:20161208-124637200
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Official Citation:John C. Platt and Alan H. Barr. 1988. Constraints methods for flexible models. SIGGRAPH Comput. Graph. 22, 4 (June 1988), 279-288. DOI=
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:72666
Deposited By: Kristin Buxton
Deposited On:08 Dec 2016 21:51
Last Modified:11 Nov 2021 05:04

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