An Approach to Surface Region Decomposition for CAD Models

Surface region decomposition of 3D models is important for shape analysis,especially local shape analysis.Traditional region decomposition methods are mostly based on mesh models not general CAD models in mechanical engineering.So,a surface region decomposition method is proposed for CAD models with boundary representations,with which the surface boundary of a solid model is divided into local convex,concave and planar regions with the minimal number.To achieve high computation efficiency,a two-pass decomposition approach is used.First,based on the classification of faces according to their local convexity,a surface boundary is initially divided into convex,concave and planar regions.Then,the decomposed regions are recursively combined to form the optimal region decomposition.Experimental results show that this approach can effectively decompose the surface boundary of CAD models.