中英文對照外文翻譯文獻(文檔含英文原文和中文翻譯)原文：Feature-BasedComponentModelsforVirtualPrototypingofHydraulicSystermAbstract:Thispaperproposesafeature-basedapproachforthevirtualprototypingofhydraulicsystems.Itpresentsaframeworkwhichallowsthedesignertodevelopavirtualhydraulicsystemprototypeinamoreintuitivemanner,i.e.throughassemblyofvirtualcomponentswithengineeringdata.Theapproachisbasedonidentifyingthedatarequiredforthedevelopmentofthevirtualprototypes,andseparatingtheinformationintobehaviour,structural,andproductattributes.Suitablerepresentationsoftheseattributesarepresented,andtheframeworkforthefeature-basedvirtualprototypingapproachisestablished,basedonthehierarchicalstructureofcomponentsinahydraulicsystem.Theproposedframeworknotonlyprovidesaprecisemodelofthehydraulicprototypebutalsooffersthepossibilityofdesigningvariationclassesofprototypeswhosemembersarederivedbychangingcertainvirtualcomponentswithdifferentfeatures.Keywords:Computer-aidedengineering;Fluidpowersystems;Virtualprototyping1.IntroductionHydraulicsystemdesigncanbeviewedasafunction-to-formtransformationprocessthatmapsanexplicitsetofrequirementsintoaphysicalrealisablefluidpowersystem.Theprocessinvolvesthreemainstages:thefunctionalspecificationstage,theconfigurationdesignstage,andtheprototypingstage.Theformatforthedescriptionofthedesignineachstageisdifferent.Thefunctionalspecificationstageconstitutestheinitialdesignwork.Theobjectiveistomapthedesignrequirements.Toachievethis,thedesignproblemsarespecifiedCorrespondenceandoffprintrequeststo:DrS.C.Fok,SchooolofMechanicalandProductionEngineering,NanyangTechnologicalUniversity,NanyangAvenue,Singapore639798.Thedesignermustidentifytheperformanceattributes,whichcanincludepressure,force,speed,andflowrate,withtherequiredpropertiessuchassize,cost,safetyandoperatingsequence.performancerequirementsforeachattribute.Inthisstage,thedesignisabstractedintermsoftheperformanceattributeswithassociatedvalues.Theobjectiveoftheconfigurationdesignstageistosynthesiseahydrauliccircuitthatperformstherequiredfunctionsconformingtotheperformancestandardswithindefinedconstraints.Atypicalhydraulicsystemismadeupofmanysubsystems.Thesmallestbuildingblockinasubsystemisthestandardhydrauliccomponent(suchasvalves,cylinders,pumps,etc.).Eachtypeofstandardcomponentservesaspecificelementalfunction.Thedesigneffortintheconfigurationdesignstageisfundamentallyasearchforasetofoptimalarrangementsofstandardcomponents(i.e.hydrauliccircuit)tofulfilthefunctionalrequirementsofthesystem.Basedonthisframework,thedesignerswouldnormallydecomposetheoverallsystemfunctionsintermsofsubfunctions.Thiswillpartitionthesearchspaceandconfinethesearchforsmallerhydraulicsubcircuitstoperformthesubfunctions.Computersareoftenusedtosupporttheconfigurationdesignprocess.Forexample,KotaandLeedevisedagraph-basedstrategytoautomatetheconfigurationofhydrauliccircuits.Afterthedevelopmentofthehydrauliccircuits,digitalsimulationtoolsareoftenusedtostudyandevaluatetheseconfigurations.Withthesetools,designerscancomparethebehaviourofdifferentcircuitsandalsoanalysetheeffectswhensubcircuitsarecombined.Intheconfigurationdesignstage,thedesignistraditionallyrepresentedasacircuitdrawingusingstandardiconstosymbolisethetypeofstandardcomponent.ThisisaformofdirectedgraphS(C,E)wherethecircuitScontainscomponentsCintheformofnodeswithrelationsbetweencomponentsdenotedbyedgesE.Theprototypingstageistheverificationphaseofthesystemdesignprocesswheretheproposedhydrauliccircuitfromtheconfigurationdesignstageisdevelopedandevaluated.Physicalprototypingaimstobuildaphysicalprototypeofthehydraulicsystem666S.C.Foketal.usingindustrialavailablecomponents.Theprocessofphysicalprototypinginvolvesthefollowing:Searchforappropriatestandardcomponentsfromdifferentmanufacturers.Pre-evaluationandselectionofcomponentsbasedonindividualcomponentcost,size,andspecification,andcompatibilityfactorsbetweencomponents.Procurementandassemblyoftheselectedcomponents.Testandevaluatethephysicalprototypebasedontheoverallsystemrequirements.Useothercomponentsorredesignthecircuit(orsubcircuits)ifnecessary.Besidesdynamics,thedevelopmentofthephysicalprototypemusttakeintoconsiderationotherfactorsincludingstructure,cost,andweight.Thedynamicsdataareusedtoconfirmthefluidpowersystembehaviourwhereasthegeometricinformationisusedtoexaminetheassemblyproperties.Thedevelopmentofthephysicalprototypewillprovidetheactualperformance,structure,andcostofthedesign.Themaindisadvantageofphysicalprototypingisthatitisverytediousandtimeconsumingtolookforasetofsuitablecombinationsofstandardcomponentsfromamongsomanymanufacturers.Althoughthebasicfunctionsofthesametypesofstandardcomponentfromdifferentmanufacturersdonotdiffer,theirdynamics,structuralandcostcharacteristicsmaynotbesimilar,becauseofdesignvariation.Hence,foragivenhydrauliccircuit,differentcombinationsofpartsfromdifferentmanufacturerscanhaveimplicationsontheresultingsystem,intermsofdynamics,structure,andcost.Valueengineeringcanbeusedatthisstagetoimprovethesystemdesignbyimprovingtheattributesatthecomponentlevel.Thisincludesmaximizingtheperformance-to-costratioandminimisingthesize-to-performanceratio.Virtualprototypingcanbeviewedasacomputer-aideddesignprocess,whichemploysmodellingandsimulatingtoolstoaddressthebroadissuesofphysicallayout,operationalconcept,functionalspecifications,anddynamicsanalysisundervariousoperatingenvironments.Themainadvantageofvirtualprototypingisthatahydraulicsystemprototypecanbeassembled,analysed,andmodifiedusingdigitalcomputerswithouttheneedforphysicalcomponents,thussavingleadtimeandcost.Themainrequirementofavirtualhydraulicsystemprototypeistoprovidethesameinformationasaphysicalprototypeforthedesignertomakedecisions.Toachievethis,thevirtualprototypemustprovidesuitableandcomprehensiverepresentationsofdifferentdata.Furthermore,transformationfromonerepresentationtoanothershouldproceedformally.Xiangetal.havereviewedthepastandcurrentcomputer-aideddesignandprototypingtoolsforfluidpowersystems.Theworkrevealedthatthecurrenttoolscouldnotprovideacompleterepresentationofthedesignabstractionsattheprototypingstagefordesignjudgement.Mostofthetoolsconcentrateonthedynamicsbehaviour.Vitalgeometricalandproductinformationthatrelatestothesystemprototypeconsiderationandevaluationisfrequentlymissing.Toadvancethedevelopmentofcomputer-aidedvirtualprototypingtoolsforfluidpowersystems,thereisaneedtoaddresstheformalrepresentationsofdifferentabstractionsofbehaviour,structural,andproductdataalongwiththeirintegration.Thispaperfocusesontheseissuesandproposestheformalismofaunifiedcomponentmodelandthetaxonomybasedonthefeature-basedapproach.InSection2,wediscussthefeature-basedapproachfocusingonthekeyinformationandtheirrepresentationsrequiredforhydraulicsystemprototyping.Section3presentsaformalismofthefeature-basedmodelandstructureforthedevelopmentofvirtualhydraulicsystemprototypes.Thestructureisillustratedwithanexample.FutureworkandconclusionsaregiveninSection4.2.Feature-BasedApproachFeaturescanbedefinedasinformationsetsthatrefertoaspectsofattributesthatcanbeusedinreasoningaboutthedesign,engineeringormanufacturingprocesses.TheconceptofusingfeaturestointegrateCAD/CAPP/CAMisnotnewandtherearemanypapersontheapplicationofthisapproachinCIM.Inalltheseapplications,thefeaturemodelisregardedasthebasiswhereasdesignbyfeaturesisthekeyfortheintegration.Todevelopafeaturemodel,therelevantinformationconcerningthedesignmustbeidentifiedandgroupedintosetsbasedonthenatureoftheinformation.Therelevantinformationshouldcontainsufficientknowledgeforactivitiessuchasdesign,analysis,test,documentation,inspection,andassembly,aswellassupportvariousadministrativeandlogisticfunctions.Designbyfeaturesistheprocessofbuildingamodelofthedesignusingfeaturesasprimitiveentities.Thefeaturemodelprovidesthestandardisationofrelevantdata.Throughthedesignbyfeaturesapproach,vitalknowledgeofthedesignwillbegeneratedandstored.Together,thefeaturemodelandthedesignbyfeaturesapproachwillprovidetheessentialinformation,whichcanbeused,notonlyforthesimultaneousconsiderationofmanydifferentconcernswiththedesign,butalsotointerfacethemanyactivitiesinthedesignrealisationprocess,includingthelifecyclesupportoperations.Themaindrawbackofthefeature-baseddesignapproachisthatthefeaturemodelshouldbeproperlydefined.Thiscanbedifficult,asfeaturesaresetsofknowledgethatareapplicationdependent.Theorganisationofthefeaturescanalsobeapplicationspecific.Non-trivialdata-managementproblemscouldariseifthefeaturemodelisnotproperlydefined.Toavoidtheseproblems,thetype,representationandstructureofthefeaturesshouldberesolvedpriortousingthefeature-baseddesignmethodology.Themainconcernwhendevelopingafeaturemodelisthatitisapplication-specific.Inthedomainofvirtualprototypingofhydraulicsystems,thedetailsoftheconstituentstandardcomponentsmustbeabletobeusedtodescribetheoverallsystem.Thecomponentfeaturesarebearersofknowledgeaboutthatpart.Tocreateasuitablefeaturemodelforhydraulicsystemdesignbasedontheassemblyofstandardcomponents,therelevantinformationassociatedwithvariousstandardcomponentsmustbeidentifiedandclassified.ThisdefinitionFeature-BasedComponentModels667ofthecomponentfeaturesetcanthenbeextendedtoencompassthesubsystemfeaturesetbasedonthehierarchicalstructurebetweenthecomponentsinthesubsystem.Inthesamemanner,ahierarchicalstructureforthehydraulicsystemfeaturerepresentationwouldevolvebyconsideringthesystemasahierarchyofsubsystems.Thenecessaryinformationrequiredforaproperdescriptionofthevirtualprototypemustbenolessthanthatderivedbythedesignerfromaphysicalprototypefordecisionmaking.Thesedatashouldgenerallyincludetheshape,weight,performanceproperties,cost,dimensions,functionalitydata,etc.Comparisonwiththephysicalprototypingprocess,theinformationrequiredforeachstandardcomponentcouldbeseparatedintothreedistinctgroups:behaviourattributes,structuralattributes,andproductattributes.2.1BehaviourAttributesThebehaviourofahydrauliccomponentcanbedefinedintermsofthedynamicscharacteristicsusedtosatisfythefunctionalrequirements.Considerahydrauliccylinderconnectedtoaload.Itsfunctionistotransmitaforcefromthestrokeofthepistontotheload.Themaximumforceitcantransmitcanbeusedtodefinethefunctionalityandthebehaviourrequirementscanbespecifiedintermsofthedesiredloadaccelerationcharacteristics.Henceforahydrauliccomponent,behaviourattributesexpressfunctionalityandcanbereflectedinthedynamicscharacteristics.Thedesignerisresponsiblefortheproperdefinitionoftheoverallsystembehaviourcharacteristicsintermsofthedesireddynamics.Astandardcomponentwillhaveitsownbehaviourandprovideaspecificfunction.Complexfunctionsthatcannotbeachievedbyasinglestandardcomponentarederivedusingacombinationofcomponents.Hence,thebehaviourofthestandardcomponentwillplayanimportantroleastheindividualbehavioursofcomponentstogetherwiththeirarrangementcanaltertheoverallsystemfunction.Thebehaviourofastandardcomponentcanbenonlinearandcanbedependentontheoperatingconditions.Whentwocomponentsarecombined,itispossiblethattheirbehaviourscaninteractandproduceundesiredorunintendedcharacteristics.Theseunwantedbehavioursareassumedtohavebeenresolvedduringtheconfigurationdesignstage.Thehydrauliccircuitusedintheprototypingstageisassumedtoberealisableandwithoutanyundesirableinteractingbehaviours.Thismeansthattheoutputbehaviourofacomponentwillprovidetheinputtothesubsequentcomponent.Therepresentationofbehavioursforhydraulicsystemshasbeenwidelyinvestigated.Theserepresentationsincludetransferfunctions,state-spaceandbondgraphs.Transferfunctions(forsingle-input–single-outputsystems)andstate-spaceequations(formultiple-input–multiple-outputsystems)arebasedontheapproximationofthedynamicsaboutanominaloperatingcondition.Thepowerbondgraphmodelisbasedonthecausaleffectsthatdescribetheenergytransformationsinthehydraulicsystem.Thisapproachisappealingforhydraulicsystemanalysis.Themaindisadvantageisthatthederivationofthedynamicsequationinabondgraphofacomplicatedfluidpowersystemcanbecomeverytedious.Asaresult,recentworkhasconcentratedontheusedofartificialintelligencetorepresentthenonlinearmappingbetweentheinputandoutputdata,whichcanbeobtainedviaexperimentalwork.Thesenonlinearmappingscanbeaccomplishedusingartificialneuralnetworks.Itisquitenaturalforahydraulicsystemdesignertouseinput–outputdatatodescribethebehaviourofahydrauliccomponent.Theconfigurationdesignofahydraulicsystemisoftenachievedthroughstepsoffunctiondecomposition.Todesignahydraulicsystem,thedesigneroftentriestodecomposethefunctionsandtheirrequirementsdowntothecomponentlevel.譯文：基于原型液壓系統特征的機構模型摘要：本文為原型液壓系統的設計提出了一種基于特征的方法。它提出了一個框架,允許設計師以更加直覺的方式開發一個真實液壓機構原型，例如，通過真實的工程學數據進行設計。這種方法是在真正原型數據的基礎上發展起來的，它可以分離信息入行為，結構，和產品屬性。這些屬性被用適當的表示法提出，并且框架為基于特點的真正原型的方法建立，根據組分等級結構在一種液壓機構。它所提出的框架不只是真實的液壓系統的一個精確模型，而且為設計成員提供了當由于某些零件的一些特性改變導致系統改變而獲得一個新的液壓系統精確模型的可能性。關鍵詞:計算機輔助工程;液壓動力系統;真實樣機1.介紹液壓機構設計可能被看作是一個為映射明確套要求入物理可實現的液壓能力系統的作用對形式變革過程。這個過程涉及三個主要階段:功能規劃階段，結構設計階段，和樣機制造階段。描述各個設計階段的所用的格式是不同的。功能的規劃是所有設計中最初的工作。為了達到這個要求，設計問題是以指定的書信和印成單行本發給新加坡南陽大道南陽技術大學機械和制造工程的DrS.C.Fok。明確地根據作用和表現。設計師必須確定產品的性能和屬性，其中包括壓力，強度，速度和流體速度，以及一些所必需的東西如尺寸大小，成本,安全要求和操作順序。其次，設計師必須敘述出各個特征的精確性能要求。在這個階段，設計以摘要的形式寫出產品的相關性能要求。結構設計階段的目標是完成一個液壓系統回路。這個回路能完成系統設計參數規定的各個功能。一種典型的液壓機構由許多子系統組成。組成子系統的最小模塊是標準液壓系統元件(譬如閥門，氣缸，液壓泵等。).每種液壓標準元件都有各自的特殊作用。結構設計階段的任務就是從根本上找到一個基本液壓元件（例如液壓回路）的布置圖。這個基本的液壓回路能達到系統的各個功能要求。根據這個結構，設計師通常把整個系統功能模塊分成一個個最基本的子函數。這樣就能隔開搜索空間，通過搜索較小一級的液壓系統基本回路去實現各個子函數的功能要求。在外觀設計過程中計算機往往會發揮很大的作用。例如，Kota和Lee想出了一個基于圖表的液壓系統回路結構的自動設計方法。在液壓回路被發展以后，人們經常被使用數字模擬實驗工具來學習和評估這些結構。通過這些工具，設計師能比較不同的電路塊的功能，并且能夠分析出這些功能塊結合后的效果。在結構設計階段，傳統上設計往往用一張回路圖來代表標準元件。這里是被(C，E)包含結構C的回路S以結的形式聯系組分之間由邊E表示的地方圖表的形式。樣機設計階段是結構設計過程中提出的液壓回路的證明階段。通過這個階段能證明結構設計中對回路的提出與評估是否正確。實際樣機的目的是建立液壓機構666S的一個物理原型。使用工業可利用的零件。涉及真實樣機的過程以下:從不同的制造商手中尋找適當的標準零件。零件的選擇和評估是建立在零件之間的成本，尺寸大小，規格和互換性等因素之上的。選擇的零件取得和裝配。根據整個系統要求測試和評估物理原型。使用其它零件或重新設計電路(或支電路)如果需要。除動力學以外，物理原型的發展必須考慮到其它因素包括結構，成本與重量。動力學數據用來確認液壓動力系統的性能，但是幾何學信息用來系統的安裝性能。物理樣機的研制將提供設計產品的真實性能，結構和設計成本。物理樣機的主要缺點是,它必須非常繁瑣和費時地從在許多制造商手中尋找一套標準零件的適當組合。由于設計的變化，從不同的制造商購買的同樣類型的標準零件的作用都不相同，他們的動力學，結構和費用特征也不可能相似。因此，為同樣的一個液壓回路，選擇不同的制造商的標準零件去組裝，所完成的系統，最后在力學、結構和產品的成本等方面也會不同。在這一過程中可以使用評估工程，通過在零件標準特性上的改變來改進在這個情況下的系統設計。其中就包括最優化的性價比率和對零件大小進行最合理的設計。真正樣機設計過程可能被觀看作為一個計算機輔助設計過程，它可以使用模擬制造和模擬仿真工具來驗證樣機的物理布局，操作，功能規格，以及在在各種各樣的操作環境下的力學分析。虛擬樣機的主要好處是,不需要實際零件，通過使用數字計算機就可以對一個液壓機構原型進行裝配和分解，因而大大的節省了時間和費用。一個真正虛擬液壓機構樣機的主要要求是，它必須能像真實的產品一樣，為設計者提供信息和幫助他們做出決定。為了達到這個要求，虛擬樣機必須提供另外