基于拟随机序列求解点到自由曲线最短距离  

Calculating Shortest Distance from Point to Free-form Curve Based on Quasi Random Sequence

作　　者：温秀兰[1] 许有熊[1] 王东霞[1] 曹未丰[1] 

机构地区：[1]南京工程学院自动化学院,江苏南京211167

出　　处：《计算机仿真》2012年第8期105-108,共4页Computer Simulation

基　　金：国家自然科学基金项目(51075198);江苏省自然科学基金项目(BK2010479)

摘　　要：自由曲线因没有已知的解析表达式,轮廓常用离散点表示。在进行计算机辅助几何设计或求解轮廓的形状误差时,无法得到计算点到自由曲线的最短距离。提出用非均匀有理B样条表示自由曲线,应用改进遗传算法重建自由曲线,基于拟随机Halton序列均匀产生数据参数值计算点到重建自由曲线最短距离。实例证实了所提出方法不仅算法简单、计算速度快,而且求得距离能够逼近理论值,精确度非常高,适于在逆向工程及自由曲线轮廓度误差精密评定中推广应用。Because free - form curve is expressed with discrete points not with analytic function, it is necessary to calculate the minimum distance from the point to free - form curve in computer aided geometry design or in solving its profile form errors. In this paper, free - form curve was expressed by non ＂ uniform rational B - spline （NURBS） and an improved Genetic Algorithm （IGA） was used to reconstruct free -form curve. Data parameter values were u- niformly generated by quasi random sequence and the shortest distance from the point to reconstructed free - form curve was calculated. Examples verified that the proposed method has not only the advantages of simple algorithm and rapid computation speed, but also high accuracy. And it is easy to be applied in inverse engineering or precision e- valuation of free - form curve profile error.

关 键 词：自由曲线 拟随机序列 改进遗传算法 最短距离 

分 类 号：TP391[自动化与计算机技术—计算机应用技术]