vehicle crashworthiness and occupants protection 1

VEHICLECRASHWORTHINESSANDOCCUPANTPROTECTIONPaulDuBoisCliffordC.ChouBahigB.FiletaTawfikB.KhalilAlbertI.KingHikmatF.MahmoodHaroldJ.MertzJacWismansEditors:PriyaPrasadJamelE.BelwafaSponsoredby:AutomotiveApplicationsCommitteeAmericanIronandSteelInstituteSouthfield,MichiganDisclaimerTheopinionsincludedinthispublicationarethoseoftheindi-vidualauthorsandinnowayrepresentendorsementoftheEdi-torsorAmericanIronandSteelInstitute(AISI)SafetyPanelmembers.copyrightc2004AmericanIronandSteelInstitute2000TownCenterSouthfield,Michigan48075PageiiiContentsIntroduction........................................................11.1MotorVehicleSafety.....................................................................11.2TheAutomobileStructure..............................................................31.3Materials......................................................................................41.4Crashworthiness...........................................................................41.5CrashworthinessGoals.................................................................51.6CrashworthinessRequirements....................................................61.7AchievingCrashworthiness...........................................................71.8CrashworthinessTests...................................................................81.9CrashworthinessModelsRequirements......................................102.1Introduction.................................................................................112.2CurrentDesignPractice..............................................................122.2.1ComparisonBetweenLMSandFE-BasedCrashworthinessProcesses.......................................................................132.2.2LumpedMass-SpringModels...............................................162.2.3LimitationsofLMSModels...................................................202.3Crash/CrushDesignTechniquesforFrontStructures..................262.3.1SomeBasicPrinciplesofDesigningforCrashEnergyManage-ment................................................................................282.3.1.1DesiredDummyPerformance........................................292.3.1.2StiffcageStructuralConcept.........................................292.3.1.3ControlledProgressiveCrushorDeformationWithLimitedIntrusion.........................................................................302.3.1.4WeightEfficientEnergyAbsorbingStructuresandSupport-ingFrame.......................................................................312.3.2ReviewofAnalyticalDesignToolsforCrashEnergyManage-ment................................................................................322.3.2.1HybridModels...............................................................322.3.2.2CollapsibleBeamFiniteElement..................................352.3.2.3DynamicEffects............................................................362.3.3NewDesignMethodology....................................................382.4AnalyticalDesignTools...............................................................402.4.1ComponentDesign..............................................................402.4.1.1CollapseModes............................................................412.4.1.2AxialCollapse...............................................................422.4.1.3BendingCollapseMathematicalModels........................612.4.1.4CombinedLoading........................................................70Pageiv2.4.1.5StructuralJoints............................................................742.4.2DesignofSubstructures.......................................................752.4.2.1GeneralAnalysisMethods............................................762.4.2.2Super-CollapsibleBeam................................................782.4.2.3Thin-WalledFiniteBeamElement.................................802.4.2.4StructuralProgramming.................................................812.5VehicleFrontStructureDesignforDifferentImpactModes..........842.5.1VehicleFrontStructureDesignforCurrentStandards...........852.5.1.1FMVSS208..................................................................852.5.1.2NCAPTest....................................................................852.5.1.3IIHSTest.......................................................................872.5.2Vehicle-to-VehicleFrontalCollisions....................................882.5.2.1PreliminaryRelationshipsinHead-onFrontalCollision..892.5.2.2StrategiesforDesigningFrontStructuresforHead-onImpact............................................................................932.5.3AssessmentofAnalyticalTools............................................982.5.4Conclusion.........................................................................1002.6References...............................................................................1023.1HistoricalBackground................................................................1113.2OverviewofExplicitFETechnology...........