Identification of Natural Sub-Domain Borders of a Digitized Part

We present a contribution to the "reverse engineering" process through a method for the extraction of edges from a digitized part. The edge determination is realized step by step by fitting locally a surface, which presents a discontinuity. To avoid long process, this fitting is started only in areas with important curvatures. These areas are automatically detected with a prior paraboloid fitting. The edges are then merged into loops, which are the natural sub-domains borders of the part. This approach enables to split the initial digitized point cloud along the edges. Each "elementary" cloud given by the process is the digitized representation of a basic surface. Such surfaces could be easier rebuilt than the initial global surface, by means of an implicit or a parametric representation. Our partition process is a first step to find CAD representation of a digitized part.