华南理工大学学报(自然科学版) ›› 2012, Vol. 40 ›› Issue (1): 53-57.

• 机械工程 • 上一篇    下一篇

数控加工中连续微线段轨迹的B样条曲线拟合

皮佑国 范德和   

  1. 华南理工大学 自动化科学与工程学院,广东 广州 510640
  • 收稿日期:2011-06-23 修回日期:2011-09-18 出版日期:2012-01-25 发布日期:2011-12-01
  • 通信作者: 皮佑国(1953-) ,男,博士,研究员,主要从事工业自动化及数控系统、嵌入式系统研究. E-mail:auygpi@ scut.edu.cn
  • 作者简介:皮佑国(1953-) ,男,博士,研究员,主要从事工业自动化及数控系统、嵌入式系统研究.
  • 基金资助:

    广东省教育部产学研结合项目( 2009B090300269)

B-Spline Curve Fitting of Consecutive Micro-Segment Trajectory in NC Machining

Pi You-guo  Fan De-he   

  1. School of Automation Science and Engineering,South China University of Technology,Guangzhou 510640,Guangdong,China
  • Received:2011-06-23 Revised:2011-09-18 Online:2012-01-25 Published:2011-12-01
  • Contact: 皮佑国(1953-) ,男,博士,研究员,主要从事工业自动化及数控系统、嵌入式系统研究. E-mail:auygpi@ scut.edu.cn
  • About author:皮佑国(1953-) ,男,博士,研究员,主要从事工业自动化及数控系统、嵌入式系统研究.
  • Supported by:

    广东省教育部产学研结合项目( 2009B090300269)

摘要: 为解决数控系统进行连续微线段加工时加减速频繁、运行速度缓慢、加工路径不连续等问题,提出了最小二乘3 次B 样条曲线逼近拟合算法,采用该算法实现对连续微线段的逼近. 文中通过分析连续微线段加工路径的几何特性,提出了采用圆弧近似法计算的弓高误差准则,并选择满足条件的可拟合点集,将拟合的曲线相对于原有路径的偏离误差控制在要求范围内. 实例仿真结果表明,该算法可在保证拟合精度的同时有效地拟合连续微直线段.

关键词: 数控机床, B 样条曲线拟合, 微线段, 最小二乘法

Abstract:

In order to overcome the frequent acceleration and deceleration,low machining feedrate and discontinuous machining path in the traditional consecutive micro-segment machining process,an algorithm of cubic B-spline
curve fitting based on the least square method is proposed to approximate the consecutive micro-segment to a Bspline curve. By analyzing the geometric characteristics of the machining path of the consecutive micro-segment,a chord error constraint based on the arc approximation is presented to pick out appropriate points and keep the deviation of the fitted curve from the original path in a required range. Simulated results indicate that the proposed algorithm can effectively fit consecutive micro-segments into B-spline curves without reducing the precision.

Key words: NC machine tool, B-spline curve fitting, micro-segment, least square method