复杂曲面特征线自动提取技术研究

复杂曲面零件的几何模型重构是逆向工程的研究重点之一,由零件表面的数字化数据提取特征线是构造几何模型的重要步骤。针对由CMM获取的三维数据“点云”,提出了基于扫描线的三维分层式方法实现特征线的自动提取,提出了基于局部增量网格扩张的三维散乱数据三角剖分算法,实现任意曲面尖锐棱线的自动提取。实践说明,通过该算法得到的复杂曲面的边界线能够满足模型重建的工程需求。

Research on automatic feature line picking up of complex curved surface

The reconstruction of geometric model of machine parts with complex curved surfaces is one of the key points of research in reverse engineering,picking up the feature line from the digitized data of parts' surfaces is an important step to construct geometric model.Directed against the 3D data "points cloud" acquired form CMM,the 3D layering method used to realize the automatic feature line picking up based on scanning line was proposed.The triangulation algorithm of 3D scattering disordered data based on partial increment mesh expansion has been put forward to realize the automatic picking up of sharp crest lines of arbitrary curved surfaces.It is illustrated through practice that the border lines of complex curved surfaces obtained by means of this algorithm could satisfy engineering needs of model reconstruction.