工业设计英文论文

1、Computer-AidedDesign40(2008)Reverseinnovativedesign-anintegratedproductdesignmethodologyXiuziYea,b,.,HongzhengLiua,LeiChena,ZhiyangChenc,XiangPanc,SanyuanZhangaaCollegeofComputerScience/StateKeyLabofCAD&CG,ZhejiangUniversity,310027Hangzhou,PRChinabSolidWorksCorporation,300BakerAvenue,Concord,MA0

2、1742,USAcCollegeofSoftwareEngineering,ZhejiangUniversityofTechnology,310014,Hangzhou,PRChinaReceived24August2006;accepted7July2007AbstractToday'sproductdesignerisbeingaskedtodevelophighquality,innovativeproductsataneverincreasingpace.Tomeetthisneed,anintensivesearchisunderwayforadvanceddesignmet

3、hodologiesthatfacilitatetheacquisitionofdesignknowledgeandcreativeideasforlaterreuse.Additionally,designersareembracingawiderangeof3Ddigitaldesignapplications,suchas3Ddigitization,3DCADandCAID,reverseengineering(RE),CAEanalysisandrapidprototyping(RP).Inthispaper,weproposeareverseengineeringinnovativ

4、edesignmethodologycalledReverseInnovativeDesign(RID).TheRIDmethodologyfacilitatesdesignandknowledgereusebyleveraging3Ddigitaldesignapplications.ThecoreofourRIDmethodologyisthedefinitionandconstructionoffeature-basedparametricsolidmodelsfromscanneddata.Thesolidmodelisconstructedwithfeaturedatatoallow

5、fordesignmodificationanditeration.Suchaconstructioniswellsuitedfordownstreamanalysisandrapidprototyping.Inthispaper,wewillreviewthecommercialavailabilityandtechnologicaldevelopmentsofsomerelevant3Ddigitaldesignapplications.WewillthenintroducethreeREmodellingstrategies:anautosurfacingstrategyfororgan

6、icshapes;asolidmodellingstrategywithfeaturerecognitionandsurfacefittingforanalyticalmodels;andacurve-basedmodellingstrategyforaccuratereversemodelling.Freeformshapesareappearingwithmorefrequencyinproductdevelopment.Sincetheir“naturalparametersarehardtodefineandextract,weproposeconstructionofafeature

7、skeletonbaseduponindustrialorregionalstandardsorbyuserinteraction.Globalandlocalproductdefinitionparametersarethenlinkedtothefeatureskeleton.Designmodificationisperformedbysolvingaconstrainedoptimizationproblem.ARIDplatformhasbeendevelopedandthemainREstrategiesandcorealgorithmshavebeenintegratedinto

8、SolidWorksasanadd-inproductcalledScanTo3D.WewillusethissystemtodemonstrateourRIDmethodologyonacollectionofinnovativeconsumerproductdesignexamples.c.2008ElsevierLtd.Allrightsreserved.Keywords:3DCAD;CAID;Reverseengineering;Productdesignmethodology;Reverseinnovativedesign;Feature-basedmodelling;Paramet

9、ricmodelling;Productdefinitionparameters;Localshapedeformation1.IntroductionDesignisapurposefulprocessinvolvingcreativethinkingandproblemsolving.Designandknowledgehaveaverystrongassociation:recollectionandapplicationofknowledgecanbeconsideredasastraightforwardandpracticaldesignprocess1-3.Emergingnew

10、techniques,devicesandtheglobalizationoftheproductmarketarepushingcreativitytoitslimit.Today'smarketisaihacterizedbyfastertime-to-market,andgreaterdemandsforfreshanddistinctiveproducts.Facingintensemarketchallenges,advanceddesignmethodologiesarebeingactivelysoughttoreducethetimerequiredfor.Corres

11、pondingauthorat:SolidWorksCorporation,300BakerAvenue,Concord,MA01742,USA.Tel.:+19783715044;fax:+19783185259.E-mailaddresses:yxz,xiuzi(X.Ye).knowledgeacquisitionindesignactivities,andtoleveragecreativity.Itisestimatedthatdesignersspendabout60%oftheirtimesearchingforinformation.Thisprocessisratedasthe

12、mostfrustratingaspectofanengineer'sdesignactivities*4+.Itisalsoconservativelyestimatedthatmorethan75%ofengineeringdesignactivitycomprisescase-baseddesignreuseofpreviousdesignknowledgetoaddressanewdesignproblem4.However,physicalmodelsandassociatedknowledge,whichareincreasedconsiderablyincomplexit

13、yandquantityduringthedesignprocess,areoftennotreused.Thisresultsinsignificanttimeandcapitallosses.Hence,designandassociatedknowledgereuseisthekeytoreducingnewproductdevelopmentcosts.Theuseof3DCAD(ComputerAidedDesign)toolsisaprominentfactorinshorteningtime-to-marketandreducing0010-4485/$-seefrontmatt

14、er.2008ElsevierLtd.Allrightsreserved.doi:10.1016/j.cad.2007.07.006X.Yeetal./Computer-AidedDesign40(2008)812-827productdevelopmentcosts.Withthewideadoptionof3DCADtechnology5,productdevelopmenthasmovedfromphysicaltodigitalmockup,andfrom2Dto3Ddesigninthelastfewdecades.3DCADhasbecomepartofacompletelydig

15、italdevelopmentprocessthatincludesdesign,modelling,simulationandtooling6,7.Asaresult,moreandmoredesignsexistin3Ddigitalformandaremaintainedinproductdatabases.Fornewdesigns,ifadigitalformofsimilarproductmodelisreadilyavailableinthedatabase,3Dsearchingtechniques4,8,9canbeusedtolocateproductmodelswiths

16、imilarshapesanddesignintent.Inthesecases,anewdesigncanbeacceleratedbythereuse,inwholeorpart,ofpreviousdesigns.3Dsearchingandreusetechniqueshavebeenextensivelyresearched10,11.Althoughtherealreadyaresomecommerciallyavailable3Dsearchengines12,3Dsearchingandreuseremainsaveryactivetopicofresearchinthedes

17、ignandmediaretrievalareas.Ontheotherhand,withtherapidadvancementof3Ddataacquisitiondevices,ReverseEngineering(RE)technologyhasgainedwideacceptanceinthedesigncommunity.ThisisespeciallytrueintheCAID(ComputerAidedIndustrialDesign)communitywherephysicalmodelssuchasclaymodelsarebuiltanddigitized.Unlikeso

18、lidmodellingCADsoftwarepackageswhichfocusonmakingwatertightsolids,REsoftwarepackagestypicallyoutputsurfacemodels.Manycommercial3DCADsoftwarepackagesarefeaturebasedwithparametricdefinitionsofthefeatures.AdefinitionofafeatureisgivenbytheFEMEX(FEatureModelingEXperts)workgroup,see,e.g.13.Afeatureisdefin

19、edasarepresentationoftheshapeaspectsofaproductthatcanbemappedtoagenericshapeandfunctionallysignificantforsomeproductlife-cyclephase14.Inpracticalterms,afeaturecanbeviewedasthebasicunitofproductinformationthatcanrepresentaspecificregion.Thetermproductcanbeareal,physicalobjectoritcanbeaprocess.Theterm

20、regiondescribesaspatialorgeometricalportionofaphysicalobjectoraprocess-orientatedportionofaprocess15.Inthispaper,weusethetermfeaturetorepresentdesignintentanddesignknowledge.High-levelshapedefinitionparameterssuchasradius,length,anglesandwidtharepresentedtothedesigners,andconstraintsbetweengeometric

21、alentitiessuchasdimensionequality,parallelism,perpendicularity,co-linearityandconcentricityareimposed.Bychangingtheseintuitiveparametersandeditingtheconstraints,differentconfigurationscanbecreatedforthesamemodel,andaproductfamilycanbeobtained.Usually,afeaturetreeisformedtorecordthehistoryofthedesign

22、process,andthefeaturecreationsequencecanbereplayed.InREsoftwarepackages,however,surfaces(usuallyfreeformsurfaces)arecreated.Whilefreeformsurfaceshaveflexibilityandallowthemanipulationstypicallyrequiredintheconceptualdesignphase,theylackedtheabilitytoexpressdesignintentorknowledgeinadetailedandexplic

23、itmanner.Althoughlow-levelshapeparameterssuchasweights,knots,andcontrolpoints16areavailabletoadjustthefreeformsurfaces,theyarecounter-intuitivetodesigners.Manyshapedeformationmethodshavebeendevelopedinthelastdecadetoincreasetheintuitivenessofthefreeformshapedeformation,andtoincreasethedesigners'

24、abilitytocontroltheshapechangesthroughmeshandsurfacedeformation.ThispaperpresentsanewproductdesignmethodologycalledReverseInnovativeDesign(RID)whichcombinesthebenefitsofthesetwoworlds,namelythedesignintentandknowledgerepresentedbyfeatureswiththeirassociateddefinitionparameters;andtheflexibilityofsha

25、pedeformation.Featureswithhigh-leveldefinitionparametersaredirectlycreatedfromscanneddataina3DCADsystem.Anewdesigncanbeobtainedbychangingthesehigh-leveldefinitionparameters,whileretainingaspectsoftheoriginaldesign.Startingfromadigitizedmodelofanexistingproductorconceptualclaymodel,acleanmeshwillbeob

26、tainedbypreprocessingofapointclouddata(e.g.registration,sampling,noisedataremoval,globalandlocalsmoothing),meshingandmeshpreprocessing(e.g.sampling,smoothing,topologyrepairandholefilling).Fromthecleanedmesh,afeaturebasedparametricsolidmodelwillbeconstructedwithnaturaldefinitionparametersbytheextract

27、ionofanalyticallyshapedfeatures.Forfreeformproductmodels,productdefinitionparameterswillbeobtainedbasedonthefeatureskeletonsextractedfromthemesh.Thenaturaldefinitionparametersofthefeaturesandtheproductdefinitionparameterswillbeusedfordesignofnewproductsandproductfamilies.OurRIDprovidesthreeREmodelli

28、ngstrategiesfordifferentusecasescenarios:Fororganicshapes,C1orC2solidmodelsareautomaticallygeneratedfromthemeshmodel.Thesolidmodelcanbeusedintheapplicationscenariossuchasmodelreferences,datatransmission,high-qualitygraphicspresentationandrapidprototyping.(2)Formoreanalyticalshapes,themeshmodelissegm

29、entedintofunctionalregionscalledsubmeshes.Featurerecognitiontechniquesareexploitedtobuildanalyticallyshapedfeaturesina3DCADpackage,resultinginhigh-levelshapecharacteristics(e.g.cylindrical,spherical,conical,extrudedorrevolvedsurfaces)andnaturalshapeparameters(e.g.radius,length,heightandangle).Submes

30、hesthatarenotanalyticalarefittedbyB-splinesurfaces.Allreconstructedsurfaceswillbeextended,trimmedandsewnintoasolid(ifpossible)inthe3DCADsoftware.(3)Shouldamoreaccuratemodelberequired,acurve-basedmodellingstrategycanbeadopted.2Dor3Dsketchescanbegeneratedbyinferringfromthemeshmodel,andcurvessuchassect

31、ioncurves,boundarycurves,andfeaturelinescanbegeneratedfromthedigitizedmodel.Fromthesecurves,loftedsurfaces(withoneortwodirectionalcurvenets)17canbegenerateddirectlywithinthe3DCADpackage.FreeformproductdesignhasbeenthemainfocusofconventionalRE.Sincetheir“natural"parametersarehardtobedefinedandex

32、tracted,inourRIDweproposedealingwithfreeformproductmodelsbyextractingglobalandlocalproductdefinitionparametersthataredefinedbyinternational,domesticorindustrialde-factostandards;orbyuser-definedkeyparameters.Designerscanproducenewdesignvariationsbyeditingtheproductdefinitionparameters.X.Yeetal./Comp

33、uter-AidedDesign40(2008)812-827Featureskeletonsareextractedfromthescanned3Dmodel,andproductdefinitionparametersarefirstobtainedfromfeatureskeletons.Theobtainedhigh-levelproductdefinitionparameterscanthenbeadjustedwhichresultsindeformationofthefeatureskeletons,andtheircorrespondingsubmeshes,andhencet

34、hefeaturesurfaces.Alternatively,localdeformationofthefeatureskeletonscanresultinthedeformationofthesubmeshes,andinduceadeformationonthefeaturesurfaces.Thesedeformationsareperformedbysolvingaconstrainedminimizationproblem.Surfacescanalsobedeformedbyusingthedeformationtoolsprovidedinthe3DCADpackages.I

35、nessence,RIDcanrapidlyproducenewdesignswithshapevariations,fromascannedphysicalorclaymodel.Thenewdesigncanthenbeanalysedgeometrically,visuallyandbyCAEanalysispackages.Otherevaluationssuchasmanufacturabilityandcostcanfollow18-21.Feedbackfromtheseanalysisandevaluationswillbeusedtomodifythedesignthroug

36、hhigh-levelproductdefinitionparametersorlocalshapedeformation,andaniterativeproductdesigncycleishenceformed.RIDisthusanintegrateddigitaldesignmethodologyincorporating3Ddigitizing,3DCADandCAID,RE,CAEanalysis,andRRIDalsoachievesseamlessdataintegrationamongRE,CAIDandCAD,andverytightdataintegrationbetwe

37、enCAD/CAID/RE,CAEanalysisandR.PThispaperisorganizedasfollows:Section2givesanoverviewofrelatedwork,includingrecentlydevelopedmodellingtechnologiessuchasimage-basedmodelling,hapticmodelling,3DdataacquisitionandREtechnologies.Section3presentstheoverallworkflowanddetaileddescriptionsofthemainprocessesof

38、ourRIDmethodology.Section4introducesthreeREmodellingstrategies:(1)automaticsurfacemodellingfororganicshapessuitableformodelreferences,graphicspresentationandrapidprototyping.(2)feature-basedREsolidmodellingwithmeshsegmentedintofunctionalsubmeshes,andanalyticallyshapedfeaturesandtheirnaturalparameter

39、sextracted.TheremainingsubmeshesarefittedbyB-splinesurfaces.Allthereconstructedsurfaceswillbeextended,trimmedandsewn.(3)CurvebasedREsurfacemodellingwithcurvessuchassectioncurvesandfeaturelinesautomaticallyextractedormanuallyconstructedbysketching,andaccuratesurfacesgeneratedusingfunctionalitiesin3DC

40、ADsoftwaresuchasloft,sweep,extrudeandrevolve.Section5focusesonfeaturedefinitionparametersforfreeformshapes,andtheextractionoffeatureskeletonandproductdefinitionparameters.Designvariationsthroughproductdefinitionparametersandfeatureskeletondeformationsarethendiscussed.Section6dealswithimplementationa

41、spectofournewdesignmethodology.ARIDplatformhasbeendevelopedandthemainREmodelingstrategiesandcorealgorithmshavebeenimplementedandintegratedintoSolidWorksasanadd-inproductcalledScanTo3D.Innovativedesignexamplesaregiveninthissectiontodemonstrateournewdesignmethodology.Section7concludesthepaperandgivesd

42、iscussionsonfutureresearchdirections.2.RelatedworkDesignisfirstofallaprocess,aprocessofthoughtandplanning.Avarietyoftechniqueshaveevolvedtofacilitatethemanipulationandpresentationofdesignideas.Withtherapidadvancesincomputertechnologies,thedesignparadigmisshifting.DigitaldesignapplicationssuchasCAID/

43、CAD,CAEanalysisandRParehelpingdesignersinconceptualizing,visualizing,prototypinganddeliveringproductmodels;andshorteningtheconcept-to-marketleadtime.Althoughphysicalmodelmakingremainsanimportantandintegralpartofindustrialdesign,virtual3Dproductmodelling,simulation,RPandtoolinghavegainedwideacceptanc

44、einproductdesignpractices.Amongthese,3Dproductmodelingstandsatthecoreofproductdevelopment.Currentcommerciallyavailabledigitaldesignapplicationsonthemarketcanbeseenfromdifferentperspectivesas3DCAD22-25forforwardanddetaileddesign,CAID26-28forconceptualandindustrialdesign,andREapplications29-31Noticeth

45、atsome3DCADsoftwarepackageshaveembeddedadd-inREpackages22-24.Allstate-of-the-art3DCADsystemsarebuiltonafeature-baseddesignparadigm.Theyhavethefollowingcharacteristics:1. Featurebased-Eachoperation(addorremove)onthegeometrywillberecognizedasafeatureinaCADsystem.2. ParametricDimensional(includeequatio

46、n)andgeometricalconstraintsareparametersinafullydefinedCADmodel.3. HistorybasedAlltheparametersandfeatureswillberecordedoncreation.Engineerscaneasilymodifytheparametersdefined.4. Designvariationsandproductfamily-Alltheparameterscanbedrivenbythedesignvariables.Aproductfamilycanbequicklycreatedinthisw

47、aywithmodelsindifferentconfigurations.CAID,ontheotherhand,isusedbyindustrialdesignerstodefineformsandappearancesoftheproducts.CAIDhasundergonerapiddevelopmentandadoptioninthelastdecade.Asavisuallycreativeactivity,someoftheCAIDtechniquesallowspontaneousmodelling,withotherstakingconsiderabletimeandeff

48、orttodefinesurfacedetails.Fig.1showsatypicalinterfaceofCAID(Studiotools)andCAD(SolidWorks).Comparedto3DCADsoftware,CAIDsoftwarehasthefollowingcharacteristics:1. Surfacemodeling3DCADsoftwareusuallyresultsinsolids,andCAIDsurfaces.2. Flexibilityindeformation-ShapescanbemodifiedmorefreelyinCAIDusingthee

49、mbeddedtools.In3DCADsystem,designerhasmoreconstraintssuchasprecision.Inconsequence,itishardtoperformfreeshapedeformation.3. MaterialrenderingBothCADandCAIDhaverichmateriallibrary,withCADfocusedonengineeringparametersforengineeringcomputationandCAEanalysis,andCAIDfocusedontextureandcolourappearance.4

50、. FlashygraphicsIngeneral,CAIDsystemhasastrongergraphicalrenderingengineforflashiergraphicaldisplayandforpresentations.X.Yeetal./Computer-AidedDesign40(2008)812-827Fig.1. ExampleinterfaceofCAID(Studiotools)vs.CADsoftwarepackage(SolidWorks).Fig.2. Exampleforimage-basedmodelling36.Theexchangeofdatabet

51、weenCAIDandCADsystemsisnotaneasytask.ApopularwayusingthedatafromCAIDinCADistosavetheCAIDsurfacesinneutralformatssuchasIGES32andSTEP33,andthenimportthemintoCADforstructuralanddetaileddesign.SomeCADsoftwarepackageshaveimplementedone-to-onedataconvertersasadd-instodirectlyimportnativeCAIDdata(e.g.Solid

52、WorkshasanaddintoimportnativeRhino3DMfiles).SuchdirectconversionwilldefinitelypreservemoreinformationthanIGES/STEP,butstillmanyCAIDparametersthatarenotsupportedbyCADwillbelost.ModellingtechnologiesareattheheartofCADandCAIDsoftwarepackages.Therehavebeenalotofdevelopmentsintheareaofmodellingtechnologi

53、esduringthelastdecade,suchasimage-basedmodelling,hapticmodelling,subdivision-basedmodellingandfreeformdeformationtechnique.Image-basedmodellingImage-basedmodellingstandsintheintersectionbetweenComputerGraphicsandComputerVision.Itfocusesonrecoveringgeometricalstructurefromuncalibratedcameras,andnumer

54、ousmethodshavebeendeveloped34-36.Itisquiteawidefieldthatcoversvarioustopicssuchasinverselighting,lightfields,layereddepthimagesand3Dreconstruction.Withinsufficientforminformationfromimages,image-basedmodellingtechniquesusuallyrelyonsomesortsofvisualcuessuchasshading,texture,motion,camerafocus,highli

55、ghts,shadows,silhouettes,inter-reflections,symmetry,lightpolarizationandfeaturessuchascornersandedges.Fig.2showsanexampleofimage-basedmodelling.HapticmodellingInhapticmodelling,designerscreateadigitalmodelusingahapticfeedbackdevice.Theywillbeabletoworkwiththeirhands,astheydointheirdailywork,usingFig

56、.3. Hapticdeviceandhapticmodellinginterface39.ahapticinterfaceformodellingproductshapes37-39.Hapticfeedbackdevicesgivetheoperatorthe"feel"ofthevirtualobject.Iftheoperatormovesacursorontoanobjectasseenviathemonitor,theyactuallyfeelitspresenceviaanelectromechanicalsystemattachedtothepointing

57、device.Fig.3showsanexampleofahapticdeviceandthemodellinginterface.Subdivision-basedmodellingSubdivisionisanalgorithmictechniquetogeneratesmoothsurfacesasasequenceofsuccessivelyrefinedpolyhedralmeshes.Itsoriginsgobackto1978whenCatmullandClark,andDooandSabinfirstproposedtogeneralizespline-patchmethods

58、tomeshesofarbitrarytopology40Y4.Subdivisionalgorithmsareexceptionallysimple,workforarbitrarycontrolmeshesandproducegloballysmoothsurfaces.Specialchoicesofsubdivisionrulesallowfortheintroductionoffeaturessuchassharpedgesintoasurface.Subdivision-basedrepresentationsofcomplexgeometrycanbemanipulatedand

59、renderedefficiently.Thismakessubdivisionahighlysuitabletoolforinteractiveanimationandconceptualmodeling,evenfornonsurfacespecialist.MoreandmorecommercialCAD/CAIDsoftwarepackageshaveadoptedsubdivisionsurfaceasanimportantmodellingmethod,forexample,CATIA24providesamodellingtoolcalledIMA(Imagine&Shape)inwhichsubdivisionsurfaceisusedasab