数控代码中的特征数据识别与处理技术研究及实现

Research and Implementation of Feature Data Recognition and Processing Technology in CNC Code

针对现有插补文献均缺乏对G01数控小线段识别处理细节的问题,提出了一种识别特征的滑动窗口法及相应的算法,将数控代码识别成直线、圆弧和自由曲线。给出了基于型值点的3次、5次NURBS分段光滑插值衔接所需的一、二阶导矢计算方法,使得各个特征之间能够达到GC1和GC2连续。运用5次NURBS插值曲线对自由曲线进行建模较3次NURBS插值曲线具有更好的连续性。对“S”样件的仿真实验与加工均验证了算法的可行性。对CNC插补计算和提高加工质量有参考价值。

Aiming at the problem that the existing interpolation literatures are lack of the processing details in recognizing small line segments expressed with G01 CNC code,a feature recognition mechanism and algorithm is proposed.By using a sliding-window method and related algorithms to recognize the CNC code,the CNC path is recognized into line-segment,circular arc,or free-curve segment.The necessary calculations of the first and the second derivatives are given in terms of value points for piece-wise smooth interpolation by cubic and quintic NURBS,so that it is possible to achieve GC1 and GC2 continuity between the features.Using quintic NURBS interpolation curves to model free curves has better continuity than cubic NURBS interpolation curves.The feasibility of the algorithm has been verified by simulation experiments and machining of"S"samples.It is referable for CNC interpolation to improve machining quality.