Articles Active Structural Vibration Control A Rev

:AReview:Publishedby:://svd.sagepub.com/cgi/alertsEmailAlerts::::):(thisarticlecites117articleshostedontheCitations©2003SAGEPublications.Allrightsreserved.Notforcommercialuseorunauthorizeddistribution.atPENNSYLVANIASTATEUNIVonApril16,2008—Inthispaperwereviewessentialaspectsin-volvedinthedesignofanactivevibrationcontrolsystem.Wepresentagenericproceduretothedesignprocessandgiveselectiveexamplesfromtheliteratureonrelevantma-terial.Togetherwithexamplesoftheirapplications,varioustopicsarebrieflyintroduced,suchasstructuremodeling,modelreduction,feedbackcontrol,feedforwardcontrol,con-trollabilityandobservability,spillover,eigenstructureassign-ment(poleplacement),coordinatecouplingcontrol,robustcontrol,optimalcontrol,stateobservers(estimators),intelli-gentstructureandcontroller,adaptivecontrol,activecon-troleffectsonthesystem,timedelay,actuator–structureinteraction,andoptimalplacementofactuators.KEYWORDS:structures,vibration,modelreduction,activecontrol,controlalgorithms,actuatordynamics,timedelay.1.IntroductionThecontrolofmechanicalandstructuralvibrationhassig-nificantapplicationsinmanufacturing,infrastructureengi-neering,andconsumerproducts.Inthemachinetoolindus-try,mechanicalvibrationdegradesboththefabricationrateandqualityofendproducts.Incivilengineeringconstructs,structuralvibrationdegradeshumancomfort.Inautomo-tiveandaerospacefields,vibrationreducescomponentlife,andtheassociatedacousticsnoiseannoyspassengers.Variousmethodshavebeenappliedtovibrationcontrolintheengineeringfield.Traditionally,passiveisolatorsanddampersareusedtoattenuatemechanicalvibrations.Forexample,installingrubbermountingbetweenthemachinesandfoundations(Harris,1997;Nakra,1998)oraddingpas-sivedamperstostructures(SoongandDargush,1997)arecommonpracticesinvibrationisolationandattenuation.Recentadvancesindigitalsignalprocessing(DSP)andsensorsandactuatorstechnologyhavepromptedinterestinactivevibrationcontrol(Inman,1989;Meirovitch,1990;Soong,1990;Preumont,2002,Clarketal.,1998).Activevibrationcontrolisavastresearchareathatincor-poratesinterdisciplinarytechnologies.Forexample,atyp-icalactivevibrationcontrolsystemisanintegrationofmechanicalandelectroniccomponentsinsynergisticcom-binationwithcomputer/microprocessorcontrol.Themajorcomponentsofanyactivevibrationcontrolsystemarethemechanicalstructureinfluencedbydisturbance(creatingunwantedvibration),sensors(toperceivethevibration),controllers(tointelligentlymakeuseofthesignalsfromthesensorsandtogeneratetheappropriatecontrolsignals),andactuators(whichcounteracttheinfluenceofthedistur-banceonthestructure).Destructiveinterferencefromtheforcesgeneratedbytheactuatorsreducesand/orcancelstheeffectsofthedisturbanceonthestructure.Inthepastfewdecades,variousmethodsofactivevibra-tioncontrolhavebeendeveloped.Thedifferentalgorithmscanbeclassifiedundertwogeneralcategories:feedbackandfeedforwardactivevibrationcontrol.Variationsofthetwogeneralmethodsexist,eachwithadvantages,disad-vantages,andlimitations.Thispaperisintendedasaguidefortheissuesinvolvedindesigninganactivecontrolsystem.Thepaperfurtherprovidesareviewofactivevibrationcontroltechniques,withexamplesfrommechanicalandcivilengineeringappli-cations.Centraltopicsarebrieflyintroducedandrelevantreferencesintheliteratureareprovided.2.DevelopmentofActiveVibrationControlSystemTheprocessofdesigninganactivecontrolsystemfortheattenuationofvibrationinmachinesandstructuresgener-allyinvolvesmanysteps.Atypicalscenarioisasfollows.1.Analyzethevibratorysystem,e.g.machineorstruc-ture,tobecontrolled.2.Obtainanidealizedmathematicalmodelofthesystemtobecontrolledutilizingtoolssuchasfiniteelementanalysisorexperimentalmodalanalysis.3.Reduceandsimplifythemodelifnecessarysothatitisamenable.4.Analyzetheresultingmodel;determineitsproperties,dynamiccharacteristics,andtypesofdisturbanceandsystemresponse.5.Quantifysensorsandactuatorsrequirementsanddecideontheirtypesandwheretheywillbeplaced.6.Analyzetheimpactofthesensorsandactuatorsontheoveralldynamiccharacteristicsofthesystem.7.Specifyperformancecriteriaandstabilitytradeoffs.8.Decideonthetypeofcontrolalgorithmtobeemployedanddesignacontrollertomeetthespecifications.9.SimulatetheresultingcontrolledsystemonacomputerandassessthepotentialtomeetrequirementsArticlesActiveStructuralVibrationControl:AReviewRabihAlkhatibandM.F.GolnaraghiDrRabihAlkhatib,PostdoctoralFellow,andProfessorM.F.Golnaraghi(C