汽车碰撞安全设计

1先进汽车碰撞安全设计先进汽车碰撞安全设计季方胜博士2引言引言IntroductionIntroductionØMotorvehicletravelistheprimarymeansoftransportationintheUnitedStates,providinganunprecedenteddegreeofmobility;ØThereareabout17millionvehiclessoldannuallyintheUnitedStates;ØYetforitsadvantages,deathsandinjuriesresultingfrommotorvehiclecrashesaretheleadingcauseofdeathforpersonsofeveryagefrom3through33.3汽车碰撞事故数据汽车碰撞事故数据VehicleAccidentDataVehicleAccidentDataØBasedonUSNationalHighwayTrafficSafetyAdministrationdata,morethan43,000peopledieannuallyonroadways,whichaccountforaround1%ofallcrash-involvedpeople;ØItisestimatedthat100,000peopledieannuallyduetocaraccidentinChina;ØFrontalimpact(??,20%fatalities),sideimpact(??,23%fatalities)androllover(2%accidents,33%fatalities)arethreemajorvehiclecrashmodes.4汽车碰撞安全系统汽车碰撞安全系统VehicleCrashSafetySystemsVehicleCrashSafetySystemsØActivecrashsafetysystems(toavoidaccidents)•Electricstabilitycontrol•Advancedobstacledetectionsystem•Drivermonitoringsystem•Emergencysteeringsystem•Lane-departuresystem...ØPassivecrashsafetysystems(toprotectoccupantswhenaccidentshappen)•Restraintsystem(seatbelt,retractor,buckle)•Supplementrestraintsystem(DAB,PAB,ICAB,SAB...)ØCombinedcrashsafetysystems(toactivateprotectionsystemsbeforeaccidentshappen)5美国汽车碰撞安全标准和要求美国汽车碰撞安全标准和要求USMotorVehicleCrashSafetyUSMotorVehicleCrashSafetyStandards&RequirementsStandards&RequirementsØTherearetwoagenciesintheUnitedStates:FederalMotorVehicleSafetyStandards(FMVSS,Government)andInsuranceInstituteforHighwaySafety(IIHS,Independent);ØFMVSSaremandatorytomeet,whileIIHSrequirementsarenotmandatorytomeet,butitsratingshavearemarkableeffectonvehicleimages.6美国联邦汽车安全标准：碰撞安全美国联邦汽车安全标准：碰撞安全FMVSS:CrashSafetyFMVSS:CrashSafetyØFMVSS201:interiorheadimpactandpolesideimpact;ØFMVSS204:steeringcontrolrearwarddisplacement;ØFMVSS208:frontalbarrierimpact&OOP;ØFMVSS214:angularpoleandMDBsideimpact;ØFMVSS216:roofcrushresistance;ØFMVSS301:rearimpactandrearsideimpactforfuelsystemintegrity.7NHTSANCAPNHTSANCAP试验和评估试验和评估NHTSANCAPTesting&RatingNHTSANCAPTesting&RatingØProvideconsumerswitheasilyunderstandablevehiclesafetyperformanceinformation;ØIncludetwocrashmodes:frontalcrash(avehiclemovingat35mphstrikingafixedbarrier)andsideimpact(a1369kgdeformablebarriermovingat38.5mphimpactingastationaryvehicle);ØStarRatingsincludefivecategories.8美国公路安全保险协会试验和评估美国公路安全保险协会试验和评估IIHSCrashSafetyTesting&RatingIIHSCrashSafetyTesting&RatingØTheIIHScrashworthinessratingprogramconsistsoffourevaluations:•40mph40%-offsetDBfrontaltest•1500kgMDBat31mphsideimpacttest•Low-speedbumpercrashtest•StaticdimensionalheadrestraintevaluationØOverallperformanceisratedasgood,acceptable,marginalorpoor.9CC--NCAPNCAP和和NCAP/IIHSNCAP/IIHS之比较之比较ComparisonofCComparisonofC--NCAPwithNCAPwithNCAPandIIHSNCAPandIIHS1500kgMDBat31mph/SID-IIs1369kgMDBat38.5mph(27°)/SID-H3950kgMDBat30mph/ESID-2SideImpact40mphN/A35mph40%-offsetDeformableBarrierFrontalImpactN/A35mph30mphFixedRigidBarrierFrontalImpactIIHSNCAPC-NCAPTable1.TestSetupTable2.2007FordFocusRatingsinChinaandUSPoor(w/oSAB)Driver«««(w/oSAB)Passenger«««SideImpactGoodN/A40%-offsetDeformableBarrierFrontalImpactN/ADriver«««««Passenger«««««««««(withSAB)FixedRigidBarrierFrontalImpactIIHSNCAPC-NCAP10安全设计挑战安全设计挑战SafetyDesignChallengeSafetyDesignChallengeØSafetystandardsandratingarechallengingautomotiveengineers,especiallycrashsafetyengineersandprovideopportunitiesaswell;ØWehavetodesignvehiclestomeetsafetystandardsandtoearnhigherratingsatreasonablecosts;ØSafetydesignisinvolvedwithbothbodystructuredesignandsafetysystemdesign.11碰撞试验设施碰撞试验设施CrashTestingFacilitiesCrashTestingFacilitiesØVehicleLevel•Fixedrigidbarrier•Fixedoffsetdeformablebarrier•Movingdeformablebarrier•Fixedrigidpole•MovingbulletvehicleØSystemLevel•SledØComponentLevel•Linearimpactor•Freemotionimpactor12试验用假人试验用假人TestDummiesTestDummiesØFrontalImpact:HybridIII50thpercentileandHybridIII5thpercentile;ØSideImpact:SID-H3(FMVSS201pole),SID-IIs(IIHS),SID-IIsFRG(FMVSS214),ESID-2RE(FMVSS214)...ØOut-of-PositionTest:HybridIII6year-old,HybridIII3year-oldandCRABI12monthold.13CAECAE碰撞模拟碰撞模拟CAECrashSimulationCAECrashSimulationØAvailabledynamicFEAcodes•LS-Dyna3d(Structure,Airbag,Occupant)•Madymo(Occupant,Airbag,Structure)•Pam-Crash(Structure,Airbag,Occupant)•Radioss(Structure,Airbag,Occupant)ØVariousFEAdummymodelsarealsodevelopedforthesecodes;ØAccuracy,efficiencyandcostsvarywithFEAcodesanddummymodels;ØApowerfulcomputersystemisabigplustocrashsimulation.14CAECAE整车模型的例子整车模型的例子ExampleofAFullVehicleCAEModelExampleofAFullVehicleCAEModelØTherearearound1,500,000elementsinthemodel,andtheelementsizeisaround10mm;ØThemodelrepresentsthedetailedstructuralcomponents;ØThemodelcanusedtosimulateallcrashmodesandtooptimizebodystructure.ØOnerunmaytakeafewdays.15CAECAE系统模型的例子系统模型的例子ExampleofASystemCAEModelExampleofASystemCAEModelØApartialbody-in-whitestructure/doorstructure;ØAFEA/ellipsoiddummy;ØSafetysystem(seatbelt,airbag...);ØUseittosimulateaspecificcrashmodeandoptimizesafetysystem;ØOnerunmaytakeafewminutesorhours.16CAECAE部件模型的例子部件模型的例子ExampleofAComponentCAEModelExampleofAComponentCAEM