摘要
面向任意输入条件的曲面等值分割方法具有通用性,但已有方法未对其界点跟踪环节进行深入探讨.为此,提出曲面等值分割中的界点跟踪算法.首先,通过循环选择当前网格单元的出入界点,构建后继网格单元,并设为当前网格单元来跟踪界点;其次,对算法中的关键技术——网格单元动态构建方法以及基于界边生长趋势预测的网格单元出入界点选择方法进行介绍;最后,针对坐标、可加工性、法向量、高斯曲率和平均曲率等面点属性设计5个分割条件集,并进行实例测试.当网格单元均仅有2个界点时,该方法与已有方法的分割精度相同;当存在网格单元有2个以上界点时,该方法的平均界点误差比已有方法降低91.78%.实验结果表明,该方法适用于更复杂的分割问题,且具有较高的分割精度和鲁棒性.
The surface iso-segmentation method with conditions as input has applicability to different segmentation situations,however,does not thoroughly investigate its boundary point(BP)tracking procedure.Therefore,we present a BP tracking algorithm for surface iso-segmentation.Firstly,the BP tracking algorithm tracks BPs by repeatedly selecting the in-BP and out-BP of the current grid unit,constructing the subsequent grid unit and setting it as the current grid unit.Secondly,the key techniques of the algorithm including grid unit dynamic construction and the in-BP and out-BP selection of grid units by reasonably predicting the boundary curve(BC)growing trend are then systematically explored.Finally,attributes including coordinate,machinability,normal,Gaussian curvature and mean curvature are used to design 5 condition sets for the iso-segmentation of several CAD surfaces.When each grid unit has only 2 BPs,our method has the same segmentation accuracy with the existing method.When there exists a grid unit which has more than 2 BPs,the average BP deviation of our method is 91.78%lower than that of the existing method.Test results show that the proposed method suits for more complicated segmentation problems,and can achieve more precise segmentation and higher robustness.
作者
胡靖尘
郑国磊
Hu Jingchen;Zheng Guolei(School of Mechanical Engineering&Automation,Beihang University,Beijing 100191)
出处
《计算机辅助设计与图形学学报》
EI
CSCD
北大核心
2023年第4期609-620,共12页
Journal of Computer-Aided Design & Computer Graphics
关键词
面等值分割
界点跟踪
网格单元动态构建
界边生长趋势预测
surface iso-segmentation
boundary point tracking
grid unit dynamic construction
boundary curve growing trend prediction
