基于广义分形维数的刀具磨损状态监测

Tool wear condition monitoring based on generalized fractal dimensions

根据多重分形理论,提出一种刀具磨损在线监测方法。采用覆盖法计算了切削加工过程中声发射(AE)信号的广义维数,得到了不同刀具磨损状态下AE信号的广义维数谱,分析了广义维数与刀具磨损状态间的关系。计算了AE信号广义维数特征距离及广义维数相关系数,通过比较各广义维数相关系数的大小,对刀具磨损状态进行了决策分类。实测信号验证结果表明,运用该方法可以对刀具磨损状态进行有效识别。

Based on multi-fractal theory,a method of on-line condition monitoring of tool wear was presented.The generalized fractal dimensions of acoustic emission （AE ）signals in cutting process were calculated using box-counting method.The generalized dimension spectrums of AE signals with respect to different tool wear condition were gained,and the relation between tool wear condition and generalized dimensions was analyzed.The feature distances and correlation coefficients of generalized dimensions of AE signals were calculated.The classification of tool wear conditions was made through comparing the values of correlation coefficients of generalized dimensions.The experimental results show that the method can be used effectively in the on-line condition monitoring of tool wear.