机电一体Mechatronics化.docx

机电一体Mechatronics化.docx

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机电一体Mechatronics化

Mechatronics

（机电一体化）

1Ablendofmechanicsandelectronics,mechatronicshascometomeanthesynergisticuseofprecisionengineering,controltheory,computerscience,andsensorandactuatortechnologytodesignimprovedproductsandprocesses.

2Thestandardclothesdryeristypicallycontrolledbyamechanicaltimer.Theuseradjuststhetimeraccordingtothesizeanddampnessoftheload.Ifthetimingdeviceisnotsetproperly,thedryingcyclemaybetooshortandthelaundrymaycomeoutwet,orthemachinecouldrunlongandwasteenergy.

3Aclothesdryer,however,mightbefittedwithasensor-basedfeedbacksystemthatletsthemachinemeasurethemoisturecontentofthefabricsortheexhaustair,andturnitselfoffwhentheloadisdry.Operatingperformanceisenhancedandenergyuseisloweredasaresult.Theredesigneddryermightevenbecheapertobuy,dependingmainlyonthecostofthecomponentsthatcomprisetheelectromechanicalcontrolsystem.

4Thecomputerdiskdrive,suchasCheetahfromSeagateTechnology,isoneofthebestexamplesofmechatronicdesignbecauseitexhibitsquickresponse,precision,androbustness.

5ManyU.S.-traineddesignengineerswouldsaythattheimproveddryeristheresultofup-to-datebutconventionaldesignpractices.Areliableyetrelativelyinaccuratemechanicaldevicewasreplacedbya"smarter"electroniccontrol.Inmuchoftherestoftheworld,however,designengineerswouldsaythatthedryerredesignfollowedtheprinciplesofmechatronics.

6Mechatronicsisnothingnew;itissimplytheapplicationofthelatesttechniquesinprecisionmechanicalengineering,controlstheory,computerscience,andelectronicstothedesignprocesstocreatemorefunctionalandadaptableproducts.This,ofcourse,issomethingmanyforward-thinkingdesignersandengineershavebeendoingforyears.

7ThevaguelyawkwardwordwasfirstcoinedinJapansome30yearsago.Sincethen,mechatronicshascometodenoteasynergisticblendofmechanicsandelectronics.Theword'smeaningissomewhatbroaderthanthetraditionaltermelectromechanics,whichtomanyconnotestheuseofelectrostaticorelectromagneticdevices.Itisalsoanamorphous,heterogeneous,andcontinuallyevolvingconceptwith1,001definitions,manyofwhicharesobroadorsonarrowtobeofseeminglymarginaluse.

8Mechatronicsismorethansemantics,however.It'sasignificantdesigntrendthathasamarkedinfluenceontheproduct-developmentprocess,internationalcompetitioninmanufacturedgoods,thenatureofmechanicalengineeringeducationincomingyears,andquiteprobablythesuccessmechanicalengineerswillhaveinbecomingteamleadersorengineeringmanagers.

DefiningMechatronics

9ForTakashiYamaguchi,whoworksatHitachiLtd.'sMechanicalEngineeringLaboratoryinIbaraki,Japan,mechatronicsis"amethodologyfordesigningproductsthatexhibitfast,preciseper

formance.Thesecharacteristicscanbeachievedbyconsideringnotonlythemechanicaldesignbutalsotheuseofservocontrols,sensors,andelectronics."Headdedthatitisalsoveryimportanttomakethedesignrobust.Computerdiskdrives,forexample,areaprimeexampleofthesuccessfulapplicationofmechatronics:

"Diskdrivesarerequiredtoprovideveryfastaccess,precisepositioning,aswellasrobustnessagainstvariousdisturbances,"hesaid.

10ForGiorgioRizzoni,associateprofessorofmechanicalengineeringatOhioStateUniversityinColumbus,mechatronicsis"theconfluenceoftraditionaldesignmethodswithsensorsandinstrumentationtechnology,driveandactuatortechnology,embeddedreal-timemicroprocessorsystems,andreal-timesoftware."Mechatronic（electromechanical）products,hesaid,exhibitcertaindistinguishingfeatures,includingthereplacementofmanymechanicalfunctionswithelectronicones,whichresultsinmuchgreaterflexibilityandeasyredesignorreprogramming;theabilitytoimplementdistributedcontrolincomplexsystems;andtheabilitytoconductautomateddatacollectionandreporting.Thediagramatleftillustratesthatmechatronicsiswheremechanics,electronics,computers,andcontrolsintersect

11"Mechatronicsisreallynothingbutgooddesignpractice,"saidMasayoshiTomizuka,professorofmechanicalengineeringattheUniversityofCalifornia,Berkeley."Thebasicideaistoapplynewcontrolstoextractnewlevelsofperformancefromamechanicaldevice."Itmeansusingmodern,cost-effectivetechnologytoimproveproductandprocessperformanceandflexibility.Inmanycases,theapplicationofcomputerandcontrolstechnologyyieldsadesignsolutionthatismoreelegantthanthepurelymechanicalapproach.Byhavingagoodideaofwhatcanbedoneusingotherthanmechanicalmeans,designfreedomincreasesandresultsimprove,accordingtoTomizuka,whoisalsoeditor-in-chiefofthequarterlyIEEE/ASMETransactionsonMechatronicsjointlypublishedbytheInstituteforElectricalandElectronicsEngineersandASME.

12Thejournal,firstpublishedinMarch1996,isanotherindicationthattheimportanceofthisinterdisciplinaryareaisbeingrecognized.Transactionscoversarangeofrelatedtechnicalareas,includingmodelinganddesign,systemintegration,actuatorsandsensors,intelligentcontrol,robotics,manufacturing,motioncontrol,vibrationandnoisecontrol,microdevicesandoptoelectronicsystems,andautomotivesystems.

TheRootsofMechatronics

13MechatronicswasfirstusedintermsofthecomputercontrolofelectricmotorsbyanengineeratJapan'sYaskawaElectricCo.inthelate1960s.ThewordhasremainedpopularinJapan,andhasbeeningeneraluseinEuropeformanyyears.AlthoughmechatronicshasbeenslowtogainindustrialandacademicacceptanceasafieldofstudyandpracticeinGreatBritainandtheUnitedStates,itsincreasinglypro

minentplaceworldwideisshownbythegrowingnumberofundergraduateandpostgraduatemechatronicscoursesnowbeingoffered.

14Manyengineerswouldcontendthatmechatronicsgrewoutofrobotics.Earlyroboticarms,thenunabletocoordinatetheirmovementsandwithoutsensoryfeedback,benefitedgreatlyfromadvancesinkinematics,dynamics,controls,sensortechnology,andhigh-levelprogramming.Thesamebatteryofmoderntechnologiesthatmaderobotsmoreflexibleandthusmoreusefulwasthenbroughttobearonthedesignofnewgenerationsofhigh-performance,adaptablemachineryofallkinds.

15Inthe1970s,mechatronicswasconcernedmostlywithservotechnologyusedinproductssuchasautomaticdooropeners,vendingmachines,andautofocuscameras.Simpleinimplementation,theapproachencompassedtheearlyuseofadvancedcontrolmethods,accordingtoTransactionseditors.

16Inthe1980s,asinformationtechnologywasintroduced,engineersbegantoembedmicroprocessorsinmechanicalsystemstoimprovetheirperformance.Numericallycontrolledmachinesandrobotsbecamemorecompact,whileautomotiveapplicationssuchaselectronicenginecontrolsandantilock-brakingsystemsbecamewidespread.

17Bythe1990s,communicationstechnologywasaddedtothemix,yieldingproductsthatcouldbeconnectedinlargenetworks.Thisdevelopmentmadefunctionssuchastheremoteoperationofroboticmanipulatorarmspossible.Atthesametime,new,smaller--evenmicroscale--sensorandactuatortechnologiesarebeingusedincreasinglyinnewproducts.Microelectromechanicalsystems,suchasthetinysiliconaccelerometersthattriggerautomotiveairbags,areexamplesofthelatteruse.

18Assignificantasthesedevelopmentsmayseem,agooddealofskepticismremainsabouttheideaofcodifyingtheminanengineeringfieldcalledmechatronics."It'scertainlyacatchyword,"saidcontrolsexpertErnestO.Doebelin,professoremeritusatOhioStateandanASMEFellow,"butit'sanevolutionary,ratherthanrevolutionary,development.Nowthatcomputersaresmallandrelativelycheap,itjustmakessensefordesignerstobuildthemintoproducts.Mechatronicsisreallythefamiliaritywithalltheothertechnologies--computers,software,advancedcontrols,sensors,actuators,andsoforth--thatmaketheadvancedproductspossible."

19SimilarsentimentswereexpressedbyDavorHrovat,seniorstafftechnicalspecialistattheFordResearchLaboratoryinDearborn,Mich.:

"Thewordsinglesoutanareathatperhapsisnotasinglearea.Mechatronicsismixtureoftechnologiesandtechniquesthattogetherhelpindesigningbetterproducts."

20Howevermechatronicsisdefined,itmeans"wenowhaveviabletechnologyforcomputercontrolofmechanicalsystemsatalllevels,fromtoasterstoautos,"saidDavidM.Auslander,professorofmechanicalengineeringatBerkeley."Todaywehavemechanicalsystemsforwhichperformance

isdefinedbywhat'sinacomputer,whetherit'ssoftwarealgorithms,neuralnetworks,orfuzzylogic.Thatalonemakesitdifferentfromanythingyoucoulddo25yearsago."

21Auslandertakesaverygeneralizedviewofthetopic."Anysysteminwhichyoucontrolormodulatepowerisacandidateforcomputercontrol.Foranymechanicalcomponentyoucanaskthequestion:

Whatisitspurpose?

Doesittransmitpower?

Orisitspurposecontrolandcoordination?

Computers,software,andelectronicscangenerallydothissecondfunctionmoreefficiently--simpler,cheaper,withmuchmoreflexibility."Thisapproach,heemphasized,constitutesatotallydifferentviewofhowmechanicalsystemsworkcomparedwithpreviousconceptions."Thisisamachineviewedfromthecontrolsoutward.

22Followingmechatronicprinciples,GeneralElectric'sProfileSuper32clotheswasherfeaturesasensor-basedfeedbackcontrolthatmaintainscorrectwatertemperaturenomattertheloadsize"

23Conside