SURFACE FITTING BASED ON OPTICAL 3-D MEASUREMENT

摘要

The aim of reverse engineering is to create a computer-aided design (CAD) model of an existing physical object. This paper deals with technology for acquiring measured point data by use of an optical 3-D measuring system. This system is suited for measuring objects, at a high speed and in a high density, which have smooth shapes and character areas with steep slopes. Smooth curves are approximated by fitting non-uniform cubic B-spline curves with curvature taken into consideration. Free-form surfaces in higher-order continuity are derived from the fitted B-spline curves as the boundary curves of patches. A strategy for remeasurement is proposed to extract character areas in order to generate a series of free-form surfaces, and techniques are also proposed to connect fitted B-spline curves with surfaces by use of pseudo vertices. The results of the experiments show that the proposed methods are effective for generating free-form surfaces.