Share Email Print
cover

Proceedings Paper

Adaptive reconstruction of closed Bezier surfaces
Author(s): George K. Knopf
Format Member Price Non-Member Price
PDF $14.40 $18.00

Paper Abstract

This paper presents a technique for reconstructing smooth closed Bezier surfaces from coordinate measurements based on a Bernstein Basis Function (BBF) network. While various neural networks, such as the backpropagation network and radial basis function networks, have been effective in functional approximation and surface fitting these neural networks produce system dependent solutions that are not easily transferable to commercially available design software. The BBF network has an advantage over other networks by directly employing the same Bernstein polynomial basis functions that are used in describing Bezier surfaces. The BBF network is capable of implementing a close approximation to any continuous nonlinear mapping by forming a linear combination of nonlinear Bernstein polynomial basis functions. Changing the number of basis neurons in the network architecture is equivalent to modifying the degree of the Bernstein polynomials. Complex smooth surfaces can be reconstructed by using several simultaneously updated networks, each corresponding to a separate surface patch. A smooth transition between adjacent Bezier surface patches can be achieved by imposing additional positional C0 and tangential C1 continuity constraints on the weights during the adaptation process. Once adapted, the final weights of the networks correspond to the control points of the Bezier surface, and can therefore be used directly in commercial CAD software packages that utilize parametric modelers.

Paper Details

Date Published: 2 February 2001
PDF: 9 pages
Proc. SPIE 4191, Sensors and Controls for Intelligent Manufacturing, (2 February 2001); doi: 10.1117/12.417239
Show Author Affiliations
George K. Knopf, Univ. of Western Ontario (Canada)


Published in SPIE Proceedings Vol. 4191:
Sensors and Controls for Intelligent Manufacturing
Peter E. Orban; George K. Knopf, Editor(s)

© SPIE. Terms of Use
Back to Top