基于B样条插值曲线直接筛选的EMD及其在机械振动信号处理中的应用  

Research of Direct Sifting EMD Based on Cubic B-Spline Interpolation Curve and Its Application in Processing Mechanical Vibrating Signals

作　　者：邱绵浩[1] 刘箐[1] 丛华[1] 

机构地区：[1]装甲兵工程学院机械工程系,北京100072

出　　处：《装甲兵工程学院学报》2007年第3期29-33,共5页Journal of Academy of Armored Force Engineering

基　　金：国家自然科学基金资助项目(50405022)

摘　　要：经典的经验模式分解（EMD）方法通过求解信号的上下2条三次样条包络曲线的均值曲线，实现对原始信号的分解。但是对于非平稳、非线性信号，包络平均无法代替真正的局部平均。另外，基于包络平均的分解方法还会引入极值过冲和欠冲问题。利用B样条的良好局部性质直接计算信号的局部均值插值曲线，克服了三次样条包络方法在EMD分解中的不足。通过对旋转机械故障振动信号的分解处理，表明基于B样条局部均值插值曲线的经验模式分解方法得到的固有模式函数更符合信号的真实物理意义，分解结果更好。In the classical EMD, calculating curve of mean of upper and lower cubic spline envelope curve decomposes original signal. But local mean cannot be substituted by envelope mean for non - linear and non- stationary signal. Otherwise, the method based on envelope mean can result in problem that the extremum overshoot and undershoot. The local mean interpolation curve of signal is directly calculated based on B - spline, which has good local property. This method conquers the shortcoming of classical EMD. The processing result manifests that the EMD based on local mean interpolation curve of cubic B - spline is better than the EMD based on cubic spline by analyzing vibrating signal of rotating machinery. The intrinsic mode functions get by ameliorated EMD accord with real physical meaning of signal.

关 键 词：经验模式分解 固有模式函数 B样条曲线 振动信号 

分 类 号：TP273[自动化与计算机技术—检测技术与自动化装置]