面向层析测量反求工程的自由曲面轮廓集分割技术

轮廓集的分割分为粗略分割和精化两个阶段．粗略分割是指从其他层上抽取和种子轮廓最相似的轮廓，提出了基于轮廓串匹配的优化方法；在精化阶段，提出了基于转角映射的特征连接点辨识技术，用来调整粗略分割轮廓段的两端点．实例表明，文中算法解决了自由曲面轮廓集精确分割的问题，为进一步实现三维特征参数识别和CAD模型重构打下了基础．

Contour Segments Extraction of Freeform Surface from Layer-Measuring Data

The extracting process can be divided into two stages: rough segmenting and refining At the former stage, an optimal method based on curvature string matching technique is put forward to find contour segments similar to the seed contour from another layer At the later stage, based on turning angle mapping and B spline fitting of planar curve, an approach to adjust the ends of the contour segment achieved at the former stage is put forward As demonstrated in the presented examples, this paper solves the problem of exact contour segmenting of freeform surfaces, which paves a way for 3 D feature parameter identification and reconstruction of CAD models