Feature extraction of machine sound using wavelet... .pdf

《Feature extraction of machine sound using wavelet... .pdf》由会员上传分享，免费在线阅读，更多相关内容在学术论文-天天文库。

1、NDT&EInternational34(2001)25±30www.elsevier.com/locate/ndteintFeatureextractionofmachinesoundusingwaveletanditsapplicationinfaultdiagnosisJingLin*StateKeyLaboratoryofAcoustics,InstituteofAcoustics,ChineseAcademyofScience,Beijing100080,People'sRepublicofChinaReceived1December1999;re

2、ceivedinrevisedform13April2000;accepted17April2000AbstractMachinesoundalwayscarriesinformationabouttheworkingofthemachine.Butinmanycases,thesoundhasaverylowSNR.Toobtaincorrectinformation,thebackgroundnoisehastoberemovedorthesoundmustbepuri®ed.Ade-noisingmethodisgiveninthispaperandi

3、ssuccessfullyusedinfeaturesoundextraction.Wecaneasilydiagnoseamachineusingthepuri®edsound.Thisde-noisingmethodisbasedonthewavelettechniqueandusestheMorletwaveletasthemotherwavelet,becauseitstime±frequencyresolutioncanbeadjustedtoadapttothesignaltobeanalyzed.Themethodisusedforextrac

4、tingthesoundofsomevehicleengineswithdifferenttypesoffailure.Thefeaturesoundisextractedsuccessfully.q2001PublishedbyElsevierScienceLtd.Keywords:Faultdiagnosis;Wavelet;Featureextraction1.IntroductionThispaperisorganizedasfollows.InSection2,theproposedde-noisingmethodisusedforasimulat

5、edsignal,Machinesoundusuallyre¯ectstheworkingconditionofwhichshowsthepowerfulcapacityofthemethodforthemachine.Manyexperiencedoperatorscandiagnoseafeatureextraction.InSection3,theexperimentalsetupismachinejustbylisteningtoitssound.Butveryoften,theintroduced.InSection4,somesignalssam

6、pledfromaballfeaturesoundofthemachineisimmersedinheavynoisebearingandthereciprocatingcompressorareprocessedforandtheoperatorscanhardlymakeoutanychangesinthefeatureextractionusingthede-noisingmethod.InSection5,sound.Also,wecannot®ndanysymptomsinthewaveformtheconclusionsaregiven.andt

7、heFourierspectrumofthesoundatthistime.Thus,toobtaintheusefulinformationthatishiddeninthenoisysignalaneffectivemethodforfeatureextractionhastobe2.Waveletanditsapplicationforfeatureextractionused.Waveletanalysisisaneffectivetoolfornonstational2.1.Reviewofwavelettransformsignalprocess

8、ingandhasbeenusedinmanyres