本文介绍了计算机集成制造(CIM)的概念，它不仅涵盖了CNC、CAD/CAM、机器人和JIT等先进技术，更是制造业业务模式的根本转变。文章比较了现代与传统制造的区别，强调了CIM中信息整合的重要性，并追溯了CIM的历史发展，从手动制造到自动化，再到现在的集成阶段。通过计算机网络的链接，实现了各个制造环节的无缝协作和实时信息共享。
附录英文原文IntroductiontoComputerIntegratedManufacturingCIMdefinedComputerintegratedmanufacturing(CIM)isthetermusedtodescribethemodemapproachtomanufacturing.AlthoughCIMencompassesmanyoftheotheradvancedmanufacturingtechnologiessuchasCNC；CAD/CAM,robotics,andjust-in-time(JIT)deliuery,itismoreth~anewtech.nolomlor.a~c~ncept.~puterintegrated:manufacturingisanentirelynewapproachtomanufacturing,anewwayofdoingbusiness.TounderstandCIM,itisnecessarytobeginwithacomparisonofmodernandtraditionalmanufacturing.Modemmanufacturingencompassesalloftheactivitiesandprocessesnecessarytoconvertrawmaterialsintofinishedproducts,deliverthemtothemarket,andsupporttheminthefield.Theseactivitiesincludethefollowing:1.Identifyinganeedforaproduct.2.Designingaproducttomeettheneeds.3.Obtainingtherawmaterialsneededtoproducetheproduct.4.Applyingappropriateprocessestotransformtherawmaterialsintofinishedproducts,5.Transportingproductstothemarket.6.Maintainingtheproducttoensureproperperformanceinthefield.Thisbroad,modernviewofmanufacturingcanbecomparedwiththemorelimitedtraditionalviewthatfocusedalmostentirelyontheconversionprocesses.Theoldapproachexcludedsuchcriticalpreconversionelements'asmarketanalysisreseach,development,anddesign,aswellassuchafter-conversionelementsasproductdeliveryandproductmaintenance.Inotherwords,intheoldapproachtomanufacturing,onlythoseprocessesthattookplaceontheshopfloorwereconsideredmanufacturing.Thistraditionalapproachofseparatingtheoverallconceptintonumerousstand-alonespecializedelementswasnotfundamentallychangedwiththeadventofautomation.WithCIM,notonlyarethevariouselementsautomated,buttheislandsofautomationarealllinkedtogetherorintegrated.Integrationmeansthatasystemcanprovidecompleteandinstantaneoussharingofinformation.Inmodernmanufacturing,integrationisaccomplishedbycomputers.CIM,then,isthetotalintegrationofallcomponentsinvolvedinconvertingrawmaterialsintofinishedproductsandgettingtheproductstothemarket.HistoricalDevelopmentofCIMThetermcomputerintegratedmanufacturingwasdevelopedinI974byJosephHarringtonasthetitleofabookhewroteabouttyingislandsofautomationtogetherthroughtheuseofcomputers.IthastakenmanyyearsforCIMtodevelopasaconcept,butintegratedmanufacturingisnotreallynew.Infact,integrationiswheremanufacturingactuallybegan.Manufacturinghasevolvedthroughfourdistictstages:Manualmanufacturing.Mechanization/SpecializationAutomation.Integration.ManualManufacturingManualmanufacturingusingsimplehandtoolswasactuallyintegratedmanufacturing.Allinformationneededtodesign,produce,anddeliveraproductwasreadilyavailablebecauseitresidedinthemindoftheonepersonwhoperformedallofthenecessarytasks,Thetoolofintegrationintheearliestyearsof,manufacturingwasthehumanmindofthecraftsmanwhodesigned,produced,anddeliveredtheproduct,Anexampleofintegratedmanualmanufacturingisthevillageblacksmithproducingaspecialtoolforalocalfarmer.Theblacksmithwouldhaveinhismindalloftheinformationneededtodesign,produce,anddeliverthefarmer'stools.Inthisexample,allelementsofmanufacturingareintegrated.Mechanization/SpecializationWiththeadventoftheindustrialrevolution,manufacturingprocessesbecamebothspecializedandmechanized.Insteadofonepersondesigning,producing,anddeliveringaproduct,workersand/ormachinesperformedspecializedtaskswithineachofthesebroadareas.Commtmicationamongtheseseparateentitieswasachievedusingdrawings,specifications,joborders,processplans,andavarietyofothercommunicationaids.Toensurethatthefinishedproductmatchedtheplannedproduct,theconceptofualitycontrolwasintroducedThepositivesideofthemechanization/specializationstagewasthatitpermittedmassproduction,interchange,abilityofparts,differentlevelsofaccuracy,anduniformity.Thedisadvantageisthatthelackofintegrationledtoagreatdealofwaste.AutomationAutomationimprovedtheperformanceandenhancedthecapabilitiesofbothpeopleandmachineswithinspecializedmanufacturingcomponents.Forexample,CADenhancedthecapabilityofdesignersanddrafters.CNCenhancedthecapabilitiesofmachinistsandcomputer-assistedplanners.Buttheimprovementsbroughtonbyautomationwereisolatedwithinindividualcomponentsorislands.Becauseofthis,automationdidnotalwaysliveuptoitspotential.Tounderstandthelimitationsofautomationwithregardtooverallproductivityimpro-vement,considerthefollowinganalogy.Supposethatvarioussubsystemsofanautomobile(i.e.,theengine,steering,brakes)wereautomatedtomakethedriver'sjobeasier.Automaticacceleration,deceleration,steering,andbrakingwouldcertainlybemoreefficientthanthemanualversions.However,considerwhatwouldhappenifthesevariousautomatedsubsystemswerenottiedtogetherinawaythatallowedthemtocommunicateandshareaccurateup-to-dateinformationinstantlyandcontinually.Onesystemmightbeattemptingtoacceleratetheautomobilewhileanothersystemwasattemptingtoapplythebrakes.Thesamelimitationsapplyinanautomatedmanufacturingsetting.Theselimitationsarewhatledtothecurrentstageinthedevelopmentofmanufacturing,integration.Integration.Withtheadventofthecomputerage,manufacturinghasdevelopedfullcircle.Itbeganasatotallyintegratedconceptand,withCIM,hasonceagainbecomeone.However,therearemajordifferencesinthemanufacturingintegrationoftodayandthatofDesignhasevolvedfromamanualprocessusingsuchtoolsassliderulesofmanufacturingarelinkedtogetherthroughthemanualeraofthepast.First,theinstrumentofintegrationinthemanualerawasthehumanmind.Theinstrumentofintegrationinmodernmanufacturingisthecomputer.Second,processesinthemodernmanufacturingsettingarestillspecializedandautomated.AnotherwaytoviewthehistoricaldevelopmentofClMisbyexaminingthewaysinwhichsomeoftheindividualcomponentsofCIMhavedevelopedovertheyears.Suchcomponentsasdesign,planning,andproductionhaveevolvedbothasprocessesandinthetoolsandequipmentusedtoaccomplishtheprocesses.pencils,scales,anderasersintoanautomatedprocessknownascomputer-aideddesign(CAD).Processplanninghasevolvedfromamanualprocessusingplanningtables,diagrams,andchartsintoanautomatedprocessknownascomputer-aidedprocessplanning(CAPP).Productionhasevolvedfromamanualprocessinvolvingmanuallycontrolledmachinesintoanautomatedprocessknownascomputer-aidedmanufacturing(CAM).Theseindividualcomponentsofmanufacturingevolvedovertheyearsintoseparateislandsofautomation.However,communicationamongtheseislandswasstillhandledmanually.Thislimitedthelevelofimprovementinproductivitythatcouldbeaccomplishedintheoverallmanufacturingprocess.Whentheseislandsandotherautomatedcomponentscomputernetworks,theselimitationscanbeovercome.
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