Accession Number : ADA291945

Title :   Object Representation for Design-Unifying Cubes and Spheres,

Corporate Author : MASSACHUSETTS INST OF TECH CAMBRIDGE

Personal Author(s) : Williams, John R. ; Pentland, Alex P.

PDF Url : ADA291945

Report Date : 1989

Pagination or Media Count : 14

Abstract : The way in which we represent physical objects in the computer greatly affects our ability to manipulate and reason about them. We are concerned with developing computer tools for conceptual design, and seek representations which are appropriate for both CAD and finite element calculations. Here, we highlight the use of superquadric functions for representing object surfaces and volumes. Using this representation bodies can be created as generic blobs and then molded, rather like clay, to the required shape using easily controlled parameters. These functions have attractive properties, including being able to represent angular bodies, such as cubes, with a smooth continuously differentiable surface. It is demonstrated that superquadrics can also be used to generate potential surfaces for plasticity. These do not have the traditional corner problems for surfaces, such as Tresca. Superquadrics can also be combined with the finite element representations to provide an efficient analysis scheme for calculating the dynamics of multi-body systems. (AN)

Descriptors :   *IMAGE PROCESSING, *COMPUTER GRAPHICS, MATHEMATICAL MODELS, COMPUTERIZED SIMULATION, ANGLES, COMPUTER AIDED DESIGN, PARAMETERS, FINITE ELEMENT ANALYSIS, EFFICIENCY, SPHERES, CONCURRENT ENGINEERING, SURFACES, RECTANGULAR BODIES, COMPUTER VISION, COMPUTER AIDED MANUFACTURING, INTERACTIVE GRAPHICS, DYNAMIC PROGRAMMING, VIRTUAL REALITY.

Subject Categories : Cybernetics
      Computer Programming and Software

Distribution Statement : APPROVED FOR PUBLIC RELEASE