Design Features Reconstruction For The Segmented Volume Of Triangular Meshes

With the rapid development of 3D scanning acquisition technology, three-dimensional digital geometric model has become a new kind of digital media, which has been obtained widespread application in many fields. Processing the digital geometry data with efficient and robust methods has become a hot topic in the study on CAD/CAM in recent years, researchers of academic and industry conduct extensive research on this. It has great significance to do the research on reconstructing feature model of the three-dimensional digital geometric meshes. The feature can reflect the high level characteristics of the design intention, and can be easy to modify and implement CAD/CAM integration.The work of this paper is a part of the study on feature model reconstruction for the triangular mesh model. For a single segmented volume of triangular meshes generated by segmentation, the design shape feature perception and automatic recognition are carried out and common used swept features and the geometric parameters of the related sections are automatically constructed. It is the foundation of reconstruction of design feature model. First of all, this paper builds the topology relationship of STL triangular mesh, using the Hash table and Balanced Binary Tree method to remove the redundant points respectively, then the merits of the two algorithms was compared. In this paper, a data structure of triangular mesh model based on coding half-edge is proposed, which is more concise and refined than the previous ones, and its ability to express the topology relationship is perfect; Secondly, this paper studies on the design feature reconstruction for an independent segmented volume of triangular mesh model. A single feature is classified as a generalized swept feature; then Gauss map, curvature estimation, centroid extraction algorithms are used to extract the characteristic parameters of it, such as cross-section and axis. Then the section contour curve is reconstructed and the original design intent restored. Finally, examples of design features reconstruction are given in the end of this paper.Algorithms mentioned in this paper were realized by programming in JhSolid software system. Experiments prove that algorithms are efficient and feasible. This work plays a role in paving the way of the follow-up feature model reconstruction.