Deforming virtual objects interactively in accordance with an elastic model

doi:10.1016/0010-4485(95)00029-1

Computer-Aided Design

Volume 28, Issue 4, April 1996, Pages 251-262

https://doi.org/10.1016/0010-4485(95)00029-1 Get rights and content

Abstract

We show how interactive deformations of a virtual 3D object can be carried out by using a hierarchical implementation of the finite element method (FEM). Basing deformations on the concepts of elasticity gives the human a measure of predictability when deciding where to apply forces to the object so that a desired shape would ensue. As is well known, one of the most powerful tools for analysing elasticity is the FEM, but the computational burden associated with a straightforward application of FEM to the problem at hand would make it too slow for any interactive process on even the fastest workstations. We have therefore developed a method in which the computational burden of FEM is alleviated by carrying out the FEM analysis at two different resolutions; a coarse resolution for a 3D calculation of the deformations and, subsequently, a finer resolution for just the surface layers of the object for a better (and smoother) delineation of the object shape. For the case of analysing the surface layers using the finer resolution, we show how a plate-theory version of FEM can be employed.

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ResearchDeforming virtual objects interactively in accordance with an elastic model

Abstract

Artifical Intelligence

Superquadrics and angle-preserving transformations

IEEE Comput. Graph. Appl.

Global and local deformations of solid primitives

SIGGRAPH

Free-form deformation of solid geometric models

SIGGRAPH

Extended free-form deformation: a sculpturing tool for 3D geometric modeling

SIGGRAPH

NURBS-based free-form deformations

IEEE Comput. Graph. Appl.

Hierarchical B-spline refinement

SIGGRAPH

Direct manipulation of free-form deformations

SIGGRAPH

A direct deformation method

Snakes: active contour models

Int. J. Comput. Vis.

Symmetry-seeking models and 3D object reconstruction

Int. J. Comput. Vis.

Elastically deformable models

SIGGRAPH

Deformable models

Vis. Comput.

Dynamic 3D models with local and global deformations: deformable Superquadrics

IEEE Trans. PAMI

Research
Deforming virtual objects interactively in accordance with an elastic model