NURBS曲线插补速度控制改进研究  

Improvement of Speed Control for NURBS Curve Interpolation

作　　者：唐明[1] 廖晓波[1] 蔡勇[1] TANG Ming;LIAO Xiaobo;CAI Yong(Key Laboratory of Testing for Manufacturing Process Ministry of Education,Southwest University of Science and Technology,Mianyang Sichuan 621010,China)

机构地区：[1]西南科技大学制造过程测试技术教育部重点实验室

出　　处：《机床与液压》2019年第10期5-9,共5页Machine Tool & Hydraulics

基　　金：高档数控机床与基础制造装备科技重大专项(2012ZX04007-021-07)

摘　　要：泰勒一阶或二阶级数展开是NURBS曲线迭代插补的常用方法,该方法会导致弦长误差进而产生速度波动。NURBS曲线插补速度控制的难点在于曲线与参数u无精确的解析关系,为完成速度规划,需要以准确的速度控制为基础。提出在二阶泰勒展开法的基础上通过界定搜索领域并采用最小偏差法来精确求取插补点参数的改进方法,实现精确的速度控制,为加减速控制提供速度控制基础。实验结果表明:改进后的速度误差的均方差减小一半,速度控制精度提升一个数量级。Taylor one or two class number expansion is a common method for NURBS curve interpolation iteration,this method will cause the chord error and speed fluctuation.The difficulty of speed control in NURBS curve interpolation is due to the no exact analytical relationship between the curve and the parameter u.In order to complete the speed planning,it needs to be based on the speed control.Based on the two order Taylor expansion method,an improved method was proposed to obtain accurately interpolate point parameters by defining the search area and using the minimum deviation method based on the second order expansion method,so as to achieve precise speed control and provide speed control basis for acceleration and deceleration control.The experimental results show that the mean square error of the improved speed error is reduced by half,and the error precision of speed control is improved by an order of magnitude.

关 键 词：NURBS曲线 速度误差 泰勒展开 加减速 

分 类 号：TP273.5[自动化与计算机技术—检测技术与自动化装置]