液压动力系统中英文对照外文翻译文献

中英文对照外文翻译文献(文档含英文原文和中文翻译)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.译文：基于原型液压系统特征的机构模型摘要：本文为原型液压系统的设计提出了一种基于特征的方法。它提出了一个框架,允许设计师以更加直觉的方式开发一个真实液压机构原型，例如，通过真实的工程学数据进行设计。这种方法是在真正原型数据的基础上发展起来的，它可以分离信息入行为，结构，和产品属性。这些属性被用适当的表示法提出，并且框架为基于特点的真正原型的方法建立，根据组分等级结构在一种液压机构。它所提出的框架不只是真实的液压系统的一个精确模型，而且为设计成员提供了当由于某些零件的一些特性改变导致系统改变而获得一个新的液压系统精确模型的可能性。关键词:计算机辅助工程;液压动力系统;真实样机1.介绍液压机构设计可能被看作是一个为映射明确套要求入物理可实现的液压能力系统的作用对形式变革过程。这个过程涉及三个主要阶段:功能规划阶段，结构设计阶段，和样机制造阶段。描述各个设计阶段的所用的格式是不同的。功能的规划是所有设计中最初的工作。为了达到这个要求，设计问题是以指定的书信和印成单行本发给新加坡南阳大道南阳技术大学机械和制造工程的DrS.C.Fok。明确地根据作用和表现。设计师必须确定产品的性能和属性，其中包括压力，强度，速度和流体速度，以及一些所必需的东西如尺寸大小，成本,安全要求和操作顺序。其次，设计师必须叙述出各个特征的精确性能要求。在这个阶段，设计以摘要的形式写出产品的相关性能要求。结构设计阶段的目标是完成一个液压系统回路。这个回路能完成系统设计参数规定的各个功能。一种典型的液压机构由许多子系统组成。组成子系统的最小模块是标准液压系统元件(譬如阀门，气缸，液压泵等。).每种液压标准元件都有各自的特殊作用。结构设计阶段的任务就是从根本上找到一个基本液压元件（例如液压回路）的布置图。这个基本的液压回路能达到系统的各个功能要求。根据这个结构，设计师通常把整个系统功能模块分成一个个最基本的子函数。这样就能隔开搜索空间，通过搜索较小一级的液压系统基本回路去实现各个子函数的功能要求。在外观设计过程中计算机往往会发挥很大的作用。例如，Kota和Lee想出了一个基于图表的液压系统回路结构的自动设计方法。在液压回路被发展以后，人们经常被使用数字模拟实验工具来学习和评估这些结构。通过这些工具，设计师能比较不同的电路块的功能，并且能够分析出这些功能块结合后的效果。在结构设计阶段，传统上设计往往用一张回路图来代表标准元件。这里是被(C，E)包含结构C的回路S以结的形式联系组分之间由边E表示的地方图表的形式。样机设计阶段是结构设计过程中提出的液压回路的证明阶段。通过这个阶段能证明结构设计中对回路的提出与评估是否正确。实际样机的目的是建立液压机构666S的一个物理原型。使用工业可利用的零件。涉及真实样机的过程以下:从不同的制造商手中寻找适当的标准零件。零件的选择和评估是建立在零件之间的成本，尺寸大小，规格和互换性等因素之上的。选择的零件取得和装配。根据整个系统要求测试和评估物理原型。使用其它零件或重新设计电路(或支电路)如果需要。除动力学以外，物理原型的发展必须考虑到其它因素包括结构，成本与重量。动力学数据用来确认液压动力系统的性能，但是几何学信息用来系统的安装性能。物理样机的研制将提供设计产品的真实性能，结构和设计成本。物理样机的主要缺点是,它必须非常繁琐和费时地从在许多制造商手中寻找一套标准零件的适当组合。由于设计的变化，从不同的制造商购买的同样类型的标准零件的作用都不相同，他们的动力学，结构和费用特征也不可能相似。因此，为同样的一个液压回路，选择不同的制造商的标准零件去组装，所完成的系统，最后在力学、结构和产品的成本等方面也会不同。在这一过程中可以使用评估工程，通过在零件标准特性上的改变来改进在这个情况下的系统设计。其中就包括最优化的性价比率和对零件大小进行最合理的设计。真正样机设计过程可能被观看作为一个计算机辅助设计过程，它可以使用模拟制造和模拟仿真工具来验证样机的物理布局，操作，功能规格，以及在在各种各样的操作环境下的力学分析。虚拟样机的主要好处是,不需要实际零件，通过使用数字计算机就可以对一个液压机构原型进行装配和分解，因而大大的节省了时间和费用。一个真正虚拟液压机构样机的主要要求是，它必须能像真实的产品一样，为设计者提供信息和帮助他们做出决定。为了达到这个要求，虚拟样机必须提供另外