摘  要：針對刀具磨損監測中信號的非平穩特性和小樣本建模中神經網絡容易陷入局部值的問題，提出基于多傳感器信號，運用集合經驗模態分解（ensemble empirical mode decomposition，EEMD）和支持向量機（support vector machine，SVM）相結合的算法，實現對刀具磨損多狀態的識別。首先對振動信號進行集合經驗模態分解，將其分解為若干個本征模態函數（intrinsic mode function，IMF）之和，然后計算得到三向切削力信號的均值和各本征模態函數分量的能量百分比值作為磨損狀態分類特征，最后運用支持向量機和Elman神經網絡對刀具在不同磨損狀態下的特征數據樣本進行訓練和識別。實驗結果證明該方法能很好地實現對刀具磨損狀態的識別，與Elman神經網絡相比，支持向量機具有更高的識別率，更適合小樣本情況下刀具磨損狀態的分類識別。
關鍵詞：刀具磨損狀態識別；集合經驗模態分解；支持向量機；多傳感器
文獻標志碼：A       文章編號：1674-5124（2016）01-0087-05
Study of tool wear based on EEMD-SVM
JIANG Yan， FU Pan， LI Xiaohui
（School of Mechanical Engineering，Southwest Jiaotong University，Chengdu 610031，China）
Abstract: To make the signals steady in cutting-tool wear monitoring and prevent neural networks from easily falling into local minimum values during small sample modeling， we have proposed a new method to identify cutting-tool wear conditions based on multi-sensor signals， ensemble empirical mode decomposition（EEMD） and support vector machine（SVM）. First， collected vibration signals are decomposed into a number of stationary intrinsic mode functions and further into the sum of multiple intrinsic mode functions. Second， these functions are used to calculate the mean value of three-direction cutting force signals and the energy percentage of each intrinsic mode function component and the calculation results were taken as the classification features of wear conditions. Next， the characteristic samples under different wear extents were trained and identified by SVM and Elman Neural Network. The experiment shows that this method can be used to determine the wear conditions of cutting tools and the SVM has a higher identification rate and more suitable for classified identification of cutting-tool wear conditions for small samples.
Keywords: tool wear condition identification； ensemble empirical mode decomposition； support vector machine； multi-sensor