基于CATIA的汽车改装式升降台数字样机建模及应用研究中英文翻译、外文文献翻译、外文翻译

附录附录AModifiedCarLiftingPlatformBasedonCATIAModelingandApplicationofDigitalPrototypingDescribestheuseofCATIAV5mechanicalpartsiandzero-dimensionalmodeling,virtualassemblyofthebasicprocesscomponentsandsteps,andwormassembly,forexampleindetail.Theeffectofimprovingthemechanicaldesigntoimprovedesignefficiencyandshortenthedesigncycletime,hassomepracticalsignificance1OverviewCATIAsoftwarefromIBMandDassaultcompanytolaunchhigh-endCAD/CAMsoftware,hasbecometheinternationalaviationindustrypreferreddesignsoftware.Withitsstrongsurfacedesignfeaturesinthemachinery,aircraft,automobile,shipbuildingandotherwidelyuseddesign,CATIAsurfacemodelingcapabilitiesisreflectedinthefeaturesandadvantagesitprovidesaveryrichmodelingtoolstosupporttheusermodelingneeds.Asitsuniquehigh-orderBeziercurveandsurfacefeatures,thenumbercanreach15,canwellmeetspecificindustrydemandingrequirementsofsurfacesmoothness.ApplicationCATlAconstructedsolidmodelcanbedirectlyappliedtootheranalysissoftwareANSYSfiniteelementanalysisCATIAsoftwarewiththree-dimensionalCADsoftwareandotherstandarddatainterfaceforeasydataconversionmodel.CATIAV5isbasedontheWindowsplatform,andtofullyparametricfeaturemodelingtechnologyasthecorefeature-basedmodelingsoftware,whichisconsistentwiththeWindows-stylemenubar,standardshortcuts,contextualmenus,multi-documentinterface,youcanmakethedifferenceWindowsapplicationstosharedata,OLEintegration,soworkquicklyandefficiently,cansignificantlyreducetrainingtime.CATIApartsassemblyisbasic,butalsothemostadvantagesandfeaturesfunctionmodules,includingthecreationofanassembly,addthespecifiedcomponentsorpartstotheassembly,theassemblyrelationshipbetweencomponentstocreate,moveandlayoutoftheassemblymembers,generatedanexplosionofproductsdiagram,assemblyinterferenceandgapanalysisandothermajorfeatures?.2three-dimensionalmodelingbasedonCATIAandassembly2.1DesignsketchesSketchdesignisthestartingpointofthree-dimensionaldesign,anditsessenceisatwo-dimensionalline,surfacedesign,softwaredesignwithatraditionaltwo-dimensionalfunctions.Parametricdesignofthebasicapproachistostartfromscratchdesign,sizeandgeometricconstraintsimposedbycreatingasketchfeature,thenapplythesize-driventechnologytoautomaticallygeneratepartsofthethree-dimensionalsolidmodel,intheuseoftechnologytogeneratetwo-dimensionalcontoursketchesdonothavetooutlinetheexactsizeoftheinput,theparametersinthefuturetogetthedesignprocess.Thus,duringtheproductdesign,youcanalwaysadjustthedesignsize,withoutaclearearlyinthedesignofthedesignsize,enhancetheeaseofCADsoftware,tobetterachieveauser-friendlydesign,butalsoforthedesignofseriesimprovementofproductsandoriginalproductsandparts"borrowed"areconvenient.2.2togeneratethree-dimensionalpartblankCATIAhasastrongthree-dimensionalsolidmodelingfunctionality,theuserplaneinthesketch,afterdrawingtwo-dimensionalgraphics,intothepartdesign(PartDesign)modules,youcanrotate,stretch,lofting,stiffened,andothermethodstogeneratethedraftthree-dimensionalpartstoberough.Constraintscanalsouseparameterizedfunctionstobemodifiedaccordingtoneed.Designerscanchangeforthebodypartblanktoachievethedesignprocessby"drawing"to"design"changes,andCATIAV5providesthree-dimensionalmodelofthespecificfeaturesmakethedesignmoresimilartotheproductionprocess,bettertoachieveacombinationofdesignandprocessing.2.3completethethree-dimensionalmodelingCATIAV5providesfeature-baseddesign,willfeatureasadesignelement,thecharacteristicsoftheproductasacombination,throughtheobjectfromtheclasstobeachievedstepbystepdescriptionofthespecificshapeofthedesign.Aftergeneratingtheroughthree-dimensionalpartscanbeusedtodrilling,slotting,shells,chamfer,plusconvexsets,suchasTwithinternalandexternalthreadsonthe"rough"to"processing",thefinalcompletionofmechanicalpartssolidmodeling.2.4completethevirtualassemblyVirtualassemblyisusingvirtualassemblytechnology,three-dimensionalcomputermodelwillbeassembledtogether,itcanavoidtheapplicationofphysicalprototypes,butalsoforpartsforclearanceandinterferencetesting,reducethesampleerrorrate.Intheproductdesignprocesscanusevarioustechniquessuchasanalysis,evaluation,simulation,andgivefullconsiderationtotheassemblyareasandrelatedproductsduringthevariouspossiblefactors.Productperformanceandfunctionalitytomeettheconditionstoimprovetheproductassemblystructure,thedesignoftheproductnotonlyassembly,andminimizeassemblycostandtotalproductcosts,shortendesigncycles.CATIA-basedvirtualassemblymodelhasparallel,bottom-upandtop-downapproachtoproductdevelopment,thisarticlefocusesonbottom-updesign.Constructthefirstmoduleinthepartsofpartsofthethree-dimensionalmodel,thencomponentsintheassemblymoduletocreateconstraintsbetweentheposition,orientationrelationships,abouttherelationshipbetweenpartstoquantifytheactualwiththevirtualassemblyprocessbetweenthevariouscomponentsentitieslocationconstraintrelationship.Inthisway,partsofthegeometryisbeingusedintheassemblyprocess,andnotsimplybecopiedtotheassembly,totrulyrealizethepartofthe"virtual"assembly.CATIAassemblyworkbenchprovidesaflexibleandintuitivetooltodeterminetherelationshipbetweenparts.Workbenchallowsuserstoassemblethecomponentpartsandvarioussub-assembliescombinedtogethertoformthefinalassemblyintheassemblyenvironment,accordingtothedefinedconstraints,partscanbemodified,analysis,andrelocationHJ.CATIAfeatureswithasingledatabase,regardlessofhoweditorseditpartsandcomponentswherethewholeassemblyofpartstomaintaintheconsistencyofassociation,ifyoumodifythecomponents,assembliesthatreferenceitautomaticallyupdated,real-timecomponentsreflectthelatestchange.Virtualassemblysteps:theassemblyprovidedinCArllAbench,leadersneedtoassemblethepartsandcomponents(CATIAprovidesthemainmethodofinsertingpartsintoparts,intotheproducts,partsandinsertnewcomponentsintoexisting,etc.).Then,theconstraintsonthecomponentsandtheestablishmentofappropriateassemblyrelationship,accordingtotherequirementsofthedifferentpartsoftheassembly,useadifferentconstraintrelations,andfinallygetacompleteassemblymodel.AndPro/EcomparedtotheassemblyprocessusingCATIAhasautomaticallycreatedtwopartstobeassembledtheirdesignbasispointsofoverlapbetweencomponentstofacilitatethedesigneracleardesignbasisbetweentheassemblyandpartsbetweenthebasedifference.3DesignExampleThewormdrive,forexample,theuseofCATIAmodelingandassemblyprocessandmethodsdescribed.3.1tocreatethree-dimensionalmodelwormAnalysisofthestructureofthewormpart,clearlythemainfeaturesofthestructuretodeterminethemodelingsteps.Byrotatingthewormbody,composedofthealveolarandkeywayparts,thebasiccharacteristicsofarotatingbody.3.1.1Createthree-dimensionalmodelofthewormpart(1)indraftmodetodrawshapesaccordingtotheroughshapeofthewormroughsketches,theestablishmentofsizeconstraints,suchassizechanges,chamfer,etc.(ofcourse,alsointheformationofroughchamferaftertheentity).(2)Inthedesignmode,theuseofrotatingparts(Shaft)tooltogeneratewormblank.(3)Accordingtotheworm'sparameters,tocalculatethealveolarpitchwormandthewormscrewaccordingtothemodeofcurvesandsurfacesgeneratedawormwrappedaroundthespiral,astheslotscanningwire.(4)SincetheendofcylindricalwormArchimedesArchimedesspiral,obliqueaxialplanetoastraightline∞],sothewormshaftcanchoosealmostplane,indraftmode,drawatrapezoid(mustbeaclosedcurve),itsdistancefromtheaxisofthebottommarginisjustthewormtoothrootradius,bothsidesoftheedgeandfaceangleof20.(Note:Thepitchatbothsidesoftheedgedistanceshouldbethepitchcirclespacewidth).(5)inthepartdesignmodeusingthenarrowslot(Slot)tooltogenerateanalveolar;usethewholearrayoftoolstowormoutofthealveolarprocess.(6)indraftmodetodrawshapeskeyway,theuseofstretchcutting(Pocket)tooltogeneratekeyslot,tocompletethethree-dimensionalconstructionofthewormMode.3.1.2createthree-dimensionalmodelwormpartsAnalysisofwormpartsofthestructure,clearlyamajorcomponentcharacteristicstodeterminethemodelingsteps.Asthewormgearandringgearteethbythecore2parts,sotheringgearandthetoothshouldbeseparatedfromthecoremodel,andthenassembled.PartsusingCATIAmodelingplatformprovidedbytheringgearandthewormweregeneratedtoothcore.3.2partsoftheassembly3.2.1ImportPartsAssemblyinCATIAprovidestheproductstructureworkbenchtoolbar,useofexistingpartsintothefunctionofthepriorconductivityhasbeendesignedwormandwormparts.3.2.2theestablishmentofbindingAspartoftheimportprocessCAITAhasestablishedaworminthewormandtheaxialprofilewidthof1/2ofthefaceoverlapconstraintrelations,haspledgeditsprofileinthewormdriveofthemain(centersection)onthealignment,inTheonlyothertwotodeterminethedirectionoftheconstraintrelationship.Centerdistancewormgearinaccordancewithrequirements(centerdistancewormandwormgearduringphysicalmodeling,basedonthegeometricparametersofwormandwormcalculated),theestablishmentofthewormandwormwheelaxisoffsetbetweentheaxisofrestrainttoensurethatthedifferencebetweenthedistancetomeetthedesignrequirements.Alongtheaxisofthewormtoestablishwormconstraintrelation,whichistoensure"inthemiddleofthewormandwormgearwormsideoftheaxisofsymmetryperpendiculartotheplane"and"wormwidth1/2symmetryonthealveolarsurfaceprofile"coincidence(Note:duringthewormandwormwheelsolidmodelingcalculationsmustbeaccurate,otherwiseitwillnotbeaccuratewormandwormwheelworkingposition)toensurethatthewormandwormgearinstalledinthecorrespondingposition.GeneratedasshowninFigure1wormdriveassemblymodel.4ConclusionCATIA3Ddesignsoftwaredesigntoolsprovideacompleteandconvenientuserinterface,theinterfaceandoptionsdesignedwithaconsistentstylewithMicrosoftproducts,greatlyreducingtheuserforthesoftwaretolearnandadapttothecycle,toalargeextentimprovedtheoperationofcomplex3Dmodelingsoftwaredefects.Meanwhile,CATIAfeature-based3Dmodelingfunctionsithasthefollowingadvantages:(1)inheritedtheuseofsolidmodelingsoftwareforproductdesign,theusercandirectlyseeonthescreenthetruethree-dimensionalmodeloftheproductcharacteristics,tomodeltheirideasclosertothebodycomposition,moreintuitivedesign.(2)parametricdesignchangestofacilitatethegraphicsize,quicklyplotted,relativetothetwo-dimensionalgraphicsmethods,designedtogreatlyreducetheworkload,especiallyinthesubsequentparametricdesignforthetechnicalstaffprovidesaneasydesign,easytomodifytheplatform,facilitatingproductserialdesign.(3)Thefeature-basedmodelingidea,theuseofBooleanoperatorsseekingintersectinglines,intersectinglines,theengineeringdrawingspeedfaster,moreaccurateline.(4)assemblymethodusingavirtualmachine,youcandirectlychecktheproductdesignspacemechanicalsystemcomponentsandassemblyofinterferenceandtofurthervisualizethedesignandanalysis,concurrentengineeringhasacertainsignificance.

附录B基于CATIA的汽车改装式升降台数字样机建模及应用研究介绍了利用CATIAV5进行机械零件i维造型以及零、部件虚拟装配的基本过程与步骤，并以蜗轮蜗杆装配为例进行详细说明。对于改善机械设计的效果、提升设计效率、缩短设计加工周期，具有一定的现实意义1概述

CATIA软件是IBM公司和Dassault公司合作推出的高端CAD／CAM软件，现已成为国际航空工业首选的设计软件。它以其强大的曲面设计功能在机械、飞机、汽车、造船等设计领域得到广泛应用，CATIA的曲面造型功能的特点和优势体现在它提供了极丰富的造型工具来支持用户的造型需求。如其特有的高次Bezier曲线曲面功能，次数能达到15，能很好地满足特殊行业对曲面光滑性的苛刻要求。应用CATlA构造的实体模型可直接应用于ANSYS等分析软件中进行有限元分析。CATIA软件具有与其他三维CAD软件标准的数据接口，方便模型数据的转换。

CATIAV5是基于Windows平台的全参数化和以特征建模技术为核心的特征造型软件，它与Windows保持一致风格的菜单条、标准的快捷键、上下关联的菜单、多文档界面、可以使不同的Windows应用程序共享数据的OLE集成，使工作快速高效，可显著减少培训时间。零件装配是CATIA基本的、也是最具优势和特色的功能模块，包括创建装配体、添加指定的部件或零件到装配体、创建部件之间的装配关系、移动和布置装配成员、生成产品的爆炸图、装配干涉和间隙分析等主要功能?。

2基于CATIA的三维造型与装配

2．1草图设计

草图设计是三维设计的起点，其实质是二维线、面设计，具有传统二维软件设计的功能。参数化设计的基本方法是从草图设计开始，通过施加尺寸和几何约束生成草图特征，再应用尺寸驱动技术自动生成零件的三维实体模型，在利用草图技术生成二维轮廓时不必输入轮廓的准确尺寸，可以在以后的参数设计过程中得到。这样，在进行产品设计时，可以随时根据需要调整设计尺寸，而不必在设计之初就明确各设计尺寸，增强了CAD软件的易操作性，更好地实现了人性化设计，而且对于设计系列产品及原产品的改进和零部件的"借用"都方便。

2．2生成三维零件毛坯

CATIA具有很强的三维实体建模的功能，当用户在草图平面绘制二维图形后，进入零件设计(PartDesign)模块，可以通过旋转、拉伸、放样、加肋、拔模等方法生成所需的三维零件毛坯。同时还可利用参数化约束功能，根据需要随时进行修改。设计者可以直接针对零件毛坯进行形体改变，实现了设计过程由"绘图"向"设计"的转变，而且CATIAV5提供的各项具体功能使三维模型的设计更类似于生产加工过程，较好地实现设计与加工的结合。

2．3完成三维造型

CATIAV5提供基于特征的设计，即将特征作为设计的单元，将产品视为特征的有机结合，通过由类到对象的逐步描述来实现具体的形状设计。在生成三维零件毛坯后，可利用打孔、开槽、抽壳、倒角、加凸台、内外螺纹等T具对"毛坯"进行"加工"，最终完成机械零件实体造型。

2．4完成虚拟装配

虚拟装配是利用虚拟装配技术，在计算机上将三维模型装配到一起，这样可避免物理原型的应用，也可对零部件进行间隙和干涉检验，减少样品差错率。能在产品设计过程中利用各种技术手段如分析、评价、仿真等，并充分考虑产品的装配环节及其相关过程中各种可能因素的影响。在满足产品性能与功能的条件下改进产品的装配结构，使设计出的产品不但可以装配，并尽可能降低装配成本和产品总成本，大大缩短设计周期。

基于CATIA的虚拟装配模式有并行、自下而上和自上而下的产品开发方法，本文重点介绍自下而上的设计方法。先在零件模块中构造各零件的三维模型，然后在装配模块中建立零部件之间的位置约束、定位关系，即将零件间的实际配合关系量化为虚拟装配过程中的各零部件实体之间的位置约束关系。这样，零部件的几何体是在装配过程中被利用，而并不是简单地被复制到装配中，真正地实现了零件的"虚拟"装配。

CATIA的装配工作台提供灵活、直观的工具，用来确定各零件间的关系。装配工作台允许用户将各个组成零件和各种子装配件组合到一起形成最终的装配体，在装配环境中，根据定义的约束，零件可以被修改、分析以及重定位HJ。CATIA具有单一数据库的特性，不管如何编辑零部件和在何处编辑零部件，整个装配部件保持关联的一致性，如果修改整个零部件，则引用它的装配件自动更新，实时反映零部件的最新变化。虚拟装配的步骤：在CArllA所提供的装配工作台上，导人需装配的零、部件(CATIA提供的插入部件的方法主要有插入部件、插入产品、插入新部件和插入已存在的部件等)。然后，对零部件进行适当的约束并建立装配关系，根据不同零件的装配要求，选用不同的约束关系，最后得到完整装配模型。

与Pro／E相比，使用CATIA进行装配的过程中已经自动建立了2个待装配零件各自的设计基准点的重合关系，便于设计者