摘要
针对B样条表达的空间自由曲线形状的相似性评价问题,提出了基于曲率特征的相似性评价算法。首先在自由曲线上等孤长均匀取点,并计算各点的曲率,得到曲线的曲率分布;然后以曲率分布作为描述空间曲线的几何特征,采用EMD(Earth Mover’s Distance)算法计算两个曲率分布的距离,衡量对应曲线的相似程度。算法以提取曲率特征的方法将三维空间曲线的相似性比较问题转化为二维分布的距离计算,简单有效地度量空间曲线形状的相似性。为检验算法的效果,以VS2010为集成开发环境对不同类型的B样条空间曲线进行大量的试验,结果表明,提出的相似性比较算法可行有效,且对旋转和取点顺序有较好的鲁棒性,能很好地反映空间曲线的相似程度。
In view of the similarity evaluation of the shape of the B-spline spatial freeform curves,the algorithm of similarity evaluation based on the curvature characteristics is proposed.Firstly,points are selected evenly on the curve,and the curvature of each point is calculated to identify the curvature distribution.Then,the curvature distribution is used to describe the geometric characteristics of the spatial curves,and the distance between the curvature distributions is calculated by EMD algorithm,in order to measure the similarity of corresponding curves.The algorithm transforms the similarity comparison among 3D curves into the calculation of distance between the dimensional distributions,and identifies the similarity of the shape of the spatial curves easily and effectively.In order to verify the algorithm,with VS2010 as an integrated element of development,a large number of experiments are carried out on different types of B-spline spatial curves.The results show that the proposed algorithm of similarity comparison is feasible and effective,with good robustness for rotation and point order,thus well reflecting the similarity of spatial curves.
作者
王洪申
汪勇
汪雨蓉
WANG Hong-shen;WANG Yong;WANG Yu-rong(School of Mechanical and Electronic Engineering,Lanzhou University of Technology,Lanzhou 730050;Tianshui Changcheng Switchgear Co.,Ltd.,Tianshui 741018)
出处
《机械设计》
CSCD
北大核心
2019年第11期91-95,共5页
Journal of Machine Design
基金
国家自然科学基金资助项目（61640207,61962035）
兰州市科技发展计划资助项目（2018-4-29）
关键词
曲率
曲率分布
EM
D
曲线相似性
curvature
curvature distribution
EMD
similarity of curves
