非均匀有理B样条在线拟合高速平滑插补法  

High-Speed Smoothing Interpolation Based on NURBS Online Fitting

作　　者：李方[1] 李迪[1] 黄昕[1,2] 

机构地区：[1]华南理工大学机械与汽车工程学院,广东广州510640 [2]广州数控设备有限公司,广东广州510165

出　　处：《华南理工大学学报（自然科学版）》2010年第8期61-65,共5页Journal of South China University of Technology(Natural Science Edition)

基　　金：国家"863"计划项目(2009AA04Z111);国家自然科学基金资助项目(50875090;50575075)

摘　　要：针对连续小线段加工平均速度低、路径不连续和振动冲击大等问题,提出了一种基于非均匀有理B样条曲线拟合的小线段平滑实时插补方法.通过分析连续小线段路径的几何特性及加工工艺,提出了连续小线段的相邻段长度比准则和相邻段临界夹角准则来选择满足要求的数据点集;根据凹凸性准则对可拟合点集分段后拟合为参数曲线,通过直线和参数曲线混合插补实现连续小线段的高速平滑加工.仿真和试验结果表明,该方法能够有效地提高加工速度,减小加工过程中的振动,同时保证加工精度.In order to avoid the low average feedrate, discontinuous machining path and strong vibration shock in the machining process of consecutive micro line blocks, a real-time smoothing interpolation method based on NURBS curve fitting is proposed. In this method, by analyzing the geometric characteristics and machining tech- nique of the consecutive lines, a length ratio criterion and a critical angle criterion of adjacent lines are presented to pick out the appropriate point sequence. The point sequence is divided into many subsections based on the concave and convex criterion and is then fitted to obtain parametric curves. Finally, by combining the linear interpolation and the parametric curve interpolation, a high-speed smoothing machining is successfully implemented. Simulated and experimental results demonstrate that the proposed method effectively improves the machining speed, reduces the machining vibration and ensures the machining accuracy.

关 键 词：非均匀有理B样条 曲线拟合 小线段 高速加工 插补 

分 类 号：TP273[自动化与计算机技术—检测技术与自动化装置]