Free-form object modeling and inspection
Zhibin Lei, Hakan Civi, David B. Cooper · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 1996
In this paper we summarize our results and methods in modeling and representing free-form objects by implicit polynomials, and outline the application of this approach to the industrial inspection problem. Implicit polynomials have been widely used in the computer vision and graphics communities for many years with their flexibility, robustness and invariant features. The effectiveness of the use of this representation hinges upon two factors; the stability of the implicit polynomial fitting procedure and the segmentation of the object shape into manageable pieces. In much of the previous work, algebraic invariants of implicit polynomials have been used for estimation or recognition. In this paper, we propose a general multi-scale free-form object modeling and recognition framework where shape information at different scale is captured by different degree and size polynomials (patchlets). We also show that pose estimation and in turn object recognition can be done without using the algebraic invariants. To accomplish this a closed-form pose solution is obtained by comparing the corresponding patchlets. An overview of a free-form object recognition and inspection system built upon these results is given in the paper.