关键词: 局部特征, 自由曲面, 曲率, 整体/局部相似性

Abstract: The existing 3D Computer Aided Design (CAD) model was mainly aimed at solid models but less considered the freeform surface,therefore a new approach to freeform surface similarity assessment based on local features was proposed.The local feature similarity assessment algorithm was employed to assess the freeform surfaces.A cloud-image of curvature was generated in parameter space,and the sift-like local features were extracted from the cloud-image.The similarity of the freeform surfaces was assessed according to the presented sift-like local features.Experimental results showed that this approach was effective and feasible,and it could realize the similarity assessment with overall/partial of freeform surface.

Key words: local features, freeform surface, curvature, overall/partial similarity