Flank Milling Cutter Path Optimization Method in Spatial Cam Machining Based on Reconstruction of NURBS Ruled Surface Driven by Sensitive Points

Abstract

Abstract: A new method to improve the tool path accuracy of frank milling was proposed based on the sensitive points affecting the NURBS ruled surface reconstruction for cam machining. The approach for the surface reconstruction was analyzed, and the curvature extreme points and the points with the maximum path error were defined as the sensitive points. The original data points was obtained by the adaptive sampling mesh planned by the curvature extreme points. Based on the least square method, the shape of the ruled surface reconstructed was modified by the constraint curve defined by the error sensitive points. At last, the numeral calculation and simulation experiments of the theoretical machining error model show the effectiveness of the algorithm.

Key words: spatial cam, flank milling, sensitive point, NURBS ruled surface, shape modification

摘要： 基于NURBS直纹面拟合敏感点的空间凸轮侧铣刀轨算法优化原理，提出了拟合误差敏感点的选择方法，根据NURBS曲面重构的原理，将曲面曲率最值点和拟合误差最大点定义为理论加工刀轨曲面误差敏感点。利用曲率敏感点，在理论非等径刀轨曲面规划离散网格，得到初始数据点。通过最小二乘优化方法重构NURBS刀轨直纹面，再根据误差敏感点定义的等参数曲线来调整刀轨直纹面形状。构建了理论加工误差模型，并通过实例的仿真计算和数值模拟说明了该算法的有效性。

关键词: 空间凸轮, 侧铣加工, 敏感点, NURBS直纹面, 形状调整

CLC Number:

TH132.47

Hu Dongfang, Zhang Wenbo. Flank Milling Cutter Path Optimization Method in Spatial Cam Machining Based on Reconstruction of NURBS Ruled Surface Driven by Sensitive Points[J]. China Mechanical Engineering.

胡东方, 张文博. 基于NURBS直纹面拟合敏感点的空间凸轮侧铣刀轨算法优化[J]. 中国机械工程.

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