小波包分析在刀具磨损状态监测中的应用研究

高龙 袁从贵

摘要：在现代化刀具工艺体系中，要保证加工品质，就亟待解决切削过程中刀具的磨损状态监测问题。采用声发射传感器SR12、测力仪Kistler9257B、振动传感器B&K4370建立了铣刀加工信号监测系统，对加工过程中获取的切削力信号和振动信号采用小波包频带能量监测法计算其频带能量，获取了与刀具磨损敏感的频段特征。结果表明，该方法对实际生产过程刀具磨损监控具有良好的应用价值。

关键词：小波包;刀具磨损;特征提取;状态监测

Application of wavelets package analysis in tool wear condition monitoring

Gao Long Yuan CongGui

DongGuan Polytechnic DongGuan 523808）

Abstract：In the modern tool technology system， in order to ensure the processing quality， it is urgent to solve the problem of monitoring the wear status of the tool during the processing. The acoustic emission sensor SR12， the force gauge Kistler9257B， and the vibration sensor B&K4370 are used to establish a milling cutter processing signal monitoring system. The cutting force signal and vibration signal obtained during the processing process are calculated using the wavelet packet frequency band energy monitoring method to calculate their frequency band energy. Frequency band characteristics sensitive to tool wear. The results show that this method has good application value for tool wear monitoring in the actual production process.

Keywords： wavelet packet; tool wear; feature extraction; condition monitoring

0引言

金屬切削加工中，刀具和工件以及刀具内部之间产生了巨大的磨擦，这势必会导致刀具的损坏[1]。刀具磨损状况会影响工件的加工精度和品质，严重时甚至会威胁机床和作业人员的生命安全，及时有效的监测刀具磨损状况，是国内外专家学者一直努力探究的重要课题。

目前国内外学者对刀具磨损的间接监测方式主要是利用振动信号、声发射信号器、切削力信号等进行监测，对刀具磨损监测信号的分析以及提取特征大多是基于其时域特征和频域特征[2]。在刀具发生磨损情况时，刀具和工件之间的摩擦力随二者接触面积的增加而相应上升，从而使得动态切削分力也产生了改变，所以通过对动态切削分力的改变情况进行监测，能够得到加工工序中的刀具不同损坏状况[3-4];而声发射则是指一种金属材料中由于塑性变形、相变、裂纹扩展等而导致应力能迅速释放所形成的应力波现象……