硕士论文-汽车内饰件模具设计和数控加工的研究

上海交通大学硕士学位论文汽车内饰件模具设计和数控加工的研究姓名：邱剑杰申请学位级别：硕士专业：材料加工工程指导教师：李从心20041101I1.2.NURBS3.UG4.UGCAM——————————CAD/CAMIIResearchonAutomotiveInteriorMouldDesignandNCManufacturingABSTRACTHigh-qualitymouldisanimportantpreconditionforthedevelopmentandimprovementofautomobilemanufacturingindustryandthequalityofitsproductsinChina.Toimprovethequalityandrealizethenationalproductionoftheautomotiveinteriors,severalresearcheshavebeendoneinthispaperbasedontheexampleofthemoulddesignofcarpetforonemodelofcarasfollows:1.Discussingtheapplication,technicalcourseandkeytechniquesofthereverseengineeringaccordingtothecurrentconditionofdevelopment.Choosingadatacolletingmethodsuitableforlargeautomotiveinteriorbymakingdetailedresearchesonthedigitalmeasuringoftheproducts.2.Exploringtheprocessesafterdatacollectionandexplainingthebasictheoryandmethodofsurfacereconstruction.Concludingaresolutiontodatacollecting,cloudpointsprocessing,NURBSsurfacereconstructionandsurfacemerging,whichissuitableforthemouldingoflargescaleautomotiveinteriors.Makingiteasierforthemodificationofthefutureproductsonthebasisof3Ddata.3.Adetailedresearchonthemouldingcharacterofautomotiveinteriorandacreativethinkingonthedesignofautomotiveinteriormould.UGsoftwareisutilizedinthemoulddesignandformation,andabrandnewprocessingtechniquecombinedwiththeadvantageofcomputeraideddesignisappliedinthepreparationofautomotiveinteriormouldstock.,whichhelpstoimprovethequalityofthedesignandshortentheperiodofdesigningandblankpreparation.4.AnalyzingandcomparingtheprocessingandcuttingparametersinvolvedinsurfaceNCprogramming.ByusingCAMofUGsoftwareandNCmachiningtechniquesaswellassettingtheparametersofroughcutting,semi-finishmachiningandfinishmachining,theperiodofprogrammingandNCmachiningaswellasthemachiningqualityareshortened.5.Summarizingawhollynumericmanufacturingflowwithadoptionofopticalscanning,surfacereconstructing,3Ddesigning,blankwoodenmouldmachining,NCprogrammingandNCmachiningwhichimprovestheprecisionofmouldmanufacturingandshortentheproducingperiod.Theproductsmadefromtheautomotiveinteriorstotallymeettheneedoftheinstallationinthevehicleswithamuchlowercostthantheimportedmouldsofthesametype.KEYWORDS:reverseengineering,surfacereconstruction,CAD/CAM,MoulddesignNCprogramming20041122þ11.14025%60%1.2a)b)21.31.2.3.1.2.3.4.CAD5.UGG1.4342.1CADCAMNCKnow-howPrescriptivemodelForwardEngineeringCADCAD(ReverseEngineering)()()[1]52.2CAD(CAE)CADCAM2-11-1Fig.1-1FlowChartofForwardEngineeringFlowChartCADCAD2-22-2Fig.2-2FlowChartofReverseEngineeringFlowChartCADCAD[2](1)(CAT)(CAD)(CAM)(CAE)(2)CAT/CAD/CAM/CAE(CIMS)606Kwok(CMM)AutoCADCMMIGES[3]MotavalliCAD2DNC:3D(NURBS)3D-CAD[4]ToletoRobert(CMM)(CMM)CMMCADRevEngACisigraphSTRIM100DELCAMCOPYCADCimatronImagewareSurfacerCADa)b)CAD3DCAD7c)CADCAD[5]d)e)CADCAD[6]f)RPMRPMRPMCAD[7]EBFCAD2.32-382-2Fig.2-2TechnologyflowchartofreverseengineeringCADCADCAD/CAM9CAD/CAMI-DEAS,ASCI,DXFCAD/CAMCAD/CAMCADCADCADCADNC(1)(2)CAD(1)(2)CADCAD2DNC(5)3DNURBS)3CAD[8]102.4CAD[9]1.2.3.4.2.5113.13.23D[10][11]CMMCMMCMM12KREON15000/s10umBoeingNCNCEOSCAN()()CTCTIGESCTlmm0.01mm3-1Chart3-1TheCompareofTypicalMeasureMethodCT133.3GOMATOS8mX8m313-1Fig.3-1theScanningoftheCarpet143-23-2Fig.3-2ScanningPointsCouldofCarpet3.4[12]3.4.1()()()CAD:15[13]()áââááâáâ3-3()()3-3Fig.3-3Automaticbreakpointdetection216[14]3dmindddmin3-43-4Fig.3-4Minimumdistancefilter3-5YmaxY=H/WYYmax17H/WThepointisremoved,ifH/W%isgreaterthanthegivenratio3-5Fig.3-5Smoothofhighwideratiomethod3-63-6Fig.3-6Densfythedatapoints[15]183-73-7Fig.3-7Orderthepoints[16][15]()3.4.2SurfacerSurfacerImageware19ImagewarelSurfacer——lVerdict——CADlBuildit——lRPM——lView——VerdictSurfacerImageware————Surfacer()SurfacerSurfacer()()Surfacer(classA)20(Fitfreeform)[](Bezier)B(NURBS)[][][][]Rainbow()(class1)Surfacer3.5f(x,y,z)0[17]CADP=P(u,v)CAD213.5.1(SurfacerModeling)[18,19]CAD/CAE/CAM1)(Ferguson)[20]2)Coons(Coons)[21]3)Bezier(Bezier)[22]4)B(Gordon)(Riesenfeld)B[23]5)NURBS(piegl)(Tiller)BB(NURBS)[24,25]6)G1[18]CADNURBS(B)NURBS80B(NURBS)BNURBS(ISO)PDES1991STEPNURBSCADNURBSNURBS[26,27](1)(2)(3)NURBS(4)NURBSNURBS22y=fxxyxyG(x,y)=0[28]p=p(u)pupp(uv)Puvuvu1uu2v1vv2[29,30]B⎩⎨⎧≤≤=+,0,1)(10,iiiuuuuN)()()(1,11111,,uNuuuuuNuuuuuNkiikikikiikiiki-++++++-+--+--=0/0=0Ni,k(u)ikikBNi,k(u)u1u11…u1k1k+2[u1u1k1]Ni,k(u)BNi,0kBNi,k(u)k-1BNi,k1(u)Ni1,k1(u)k-1BuikBNi,k(u)[u1u1k1]Bui()BBBBBNi,0(u)(3-8(a))BNi,1(u)BNi,0(u)Ni1,0(u)21112211,0)/()()/()()(+++++++≤≤≤≤⎪⎩⎪⎨⎧----=iiiiiiiiiiiuuuuuuuuuuuuuuuN3-8(b)BNi,1(u)Ni1,1(u)BNi,2(u)3-8(c)233-8BFig.3-8BSplinefunctionB∑==nikiiuNdup0,)()(di,(i=0,1,...,n)BNi,k(u)ii=0,1,...,n)kB3-9BBn(3-9Bn=3)1,2,34B3-9BFig.3-9GeneratedBSplinefunctionkXlB24∑∑===minjljkijivNuNdvup00,,,)()(),(BB(NURBS)B()kB(NURBS)∑∑===ninikiikiiiuNuNdup00,,)(/)()(wwùi(i=01n)dii=01n)ù0ùn0ùi0ùididiùiùi0,diùi--+diNURBSkXlNURBS∑∑∑∑=====minjljkijiminjljkijijivNuNvNuNdvup00,,,00,,,,)()()()(),(wwNURBSNURBSdijùiji01…mj01…nukvluU[u0u1umk1]vV[v0v1vm+l+1]klUV3.5.2ImagewareSurfacerNURBSB(NURBS)NURBSNURBSSURFACENURBS3-10253-10Fig.3-10Flowchartofsurfacesfittinginreverseengineering3DSYRFACENURBS3