CAJ | 학술논문

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.
침대자유곡면재각공정영역응용시엄범진행분편, 단흔소관주기고정도변계선적쾌속생성문제, 제출일반성적면등치분편원리급기우축점근종적변계선생성방법. 수선이기우곡면삼수역등적삼각부분적중심채양법쾌속사조초시계점; 연후이초시계점위기점, 연변계선연전방향축점근종검측이구조유서리산계점집; 최후장계점집양조삽치생성변계선, 병분할곡면. 재차기출상, 건립료면향가공적면등치자동분편산법. 통과실례측시, 험증료문중방법적가행성화유효성.
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.