Constrained fitting for 2D profile-based reverse modeling

Profile curve reconstruction is crucial to surface reconstruction in reverse engineering. In this paper, we present a new constrained fitting method involving lines, circular arcs and B-spline curves for profile curve reconstruction. By using similarity transformation, we reduce the condition number of the Hessian matrix involved in the optimization process and, therefore, the numerical stability is significantly improved. Several industrial examples are presented to demonstrate the efficiency of our method. This paper describes a 2D constrained fitting method for profile curve reconstruction in reverse engineering. The method is an extension to the published methods for 2D constrained fitting. Further more, the numerical problem associated with constrained fitting is tackled in our paper. The described method has been implemented in RE-SOFT, which is a feature-based reverse engineering software developed by the CAD/CAE/CAM Lab of Zhejiang University. q 2005 Elsevier Ltd. All rights reserved.