B-样条曲面的局部形状改进算法  

An Algorithm of Local Shape Improvement for Bicubic B-Spline Surfaces

作　　者：王洪亮[1] 王小椿[1] 

机构地区：[1]西安交通大学机械学院,西安710049

出　　处：《工程数学学报》2000年第4期86-90,共5页Chinese Journal of Engineering Mathematics

摘　　要：提出了一种双三次 B-样条曲面局部形状改进算法。首先根据节点处三阶不连续性的近似局部光顺准则 ,选择曲面待光顺的节点 ;然后利用约束的最小二乘逼近法修改相应的局部控制顶点网 ,从而降低曲面局部的三阶不连续性 ,使局部形状得到改进。在详细描述算法原理后 ,给出了算法的实现步骤。An algorithm of local shape improvement for bicubic B spline surfaces is proposed. According to the approximate local fairness criterion the sum of third order discontinuity at parametric knots ,the knot at which surface fairing will be caried out is first selected.By means of constrained least squares approximation,local control net is modified to reduce the local third order discontinuity.Thus the local shap is improved. Both principle and implementary steps of the algorithm are presented.

关 键 词：光顺 节点 三阶不连续性 算法 B-样条曲面 CAGD 

分 类 号：TP391.72[自动化与计算机技术—计算机应用技术] O18[自动化与计算机技术—计算机科学与技术]