摘要
针对自由曲面在各工程领域应用时广泛进行分片,但很少关注其高精度边界线的快速生成问题,提出一般性的面等值分片原理及基于逐点跟踪的边界线生成方法.首先以基于曲面参数域等积三角剖分的重心采样法快速查找初始界点;然后以初始界点为起点,沿边界线延展方向逐点跟踪检测以构造有序离散界点集;最后将界点集样条插值生成边界线,并分割曲面.在此基础上,建立了面向加工的面等值自动分片算法.通过实例测试,验证了文中方法的可行性和有效性.
Although segmentation of a free-form surface is widely used in engineering field, little work has been done on generating the accurate boundary curves of surface patches. In this paper, a general method of iso-surface segmentation and a novel approach based on pointwise tracking for boundary curve generation are presented. Firstly, the initial boundary point is found through gravity center sampling based on the theory of equi-area triangulation of parametric space. Secondly, starting from the initial boundary point, a set of boundary points are generated along the boundary curves by pointwise tracking. Thirdly, the boundary curves are defined through spline interpolation of all these points. Finally, an algorithm of automatic iso-surface segmentation for NC machining is established and examples are given to illustrate the validity and effectiveness of the approach.
出处
《计算机辅助设计与图形学学报》
EI
CSCD
北大核心
2015年第5期924-929,共6页
Journal of Computer-Aided Design & Computer Graphics
基金
国家科技重大专项(2012ZX 04010051)
北京航空航天大学研究生创新实践基金
关键词
自由曲面
等值分片
逐点跟踪
三角剖分
样条插值
free-form surface
iso-surface segmentation
pointwise tracking
triangulation
spline interpolation
