PAIRED SIDE IMPACT CRASH TESTING of a 15 ? PAIRED SIDE IMPACT CRASH TESTING of a 15 PASSENGER VAN

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15PassengerVanSafetyReviewPhaseIII:TRANSPORTCANADAPAIREDSIDEIMPACTCRASHTESTINGofa15PASSENGERVAN&anMFABINTERNALRESEARCHREPORTASFB11 05October5,2012PAIREDCRASHTESTINGofa15PASSENGERVAN&MFAB ii DISCLAIMERThisresearchreportwaspreparedbyTransportCanadaandisnotmeanttocritiqueorendorseanycommercialvehicleorproduct.ItismeanttoinformTransportCanadasgeneralapproachtovehiclesafetyissuesandsuggestpolicyoptions.Thisisanunpublishedreportandanycitationofitshouldindicatethis. PAIREDCRASHTESTINGofa15PASSENGERVAN&MFAB iii TABLEOFCONTENTSTABLEOFCONTENTS....................................................................................................................................iiiTABLEOFFIGURES.......................................................................................................................................ivEXECUTIVESUMMARY..................................................................................................................................vINTRODUCTION.............................................................................................................................................1TESTMEHODOLOGY......................................................................................................................................2TestVehicles:............................................................................................................................................2Striking(Bullet)Vehicles:..........................................................................................................................2CrashConfiguration:.................................................................................................................................2CrashTestDummiesandPlacementInTestVehicles:.............................................................................3CAMERASandPLACEMENT:.....................................................................................................................4Instrumentation........................................................................................................................................5RESULTS........................................................................................................................................................6VehicleKinematics....................................................................................................................................6VehicleIntrusion.......................................................................................................................................9OccupantKinematics..............................................................................................................................10Frontrowkinematics:.........................................................................................................................12Secondrowkinematics:......................................................................................................................13Thirdrowkinematics:.........................................................................................................................15InjuryMeasures......................................................................................................................................19StrucksideOccupants.........................................................................................................................21Farside(nonstruck)Occupants.........................................................................................................22DISCUSSION.................................................................................................................................................23StrucksideOccupants.........................................................................................................................23NonStrucksideOccupants.................................................................................................................26CONCLUSION...............................................................................................................................................27FUTUREWORK............................................................................................................................................29REFERENCES................................................................................................................................................29 PAIREDCRASHTESTINGofa15PASSENGERVAN&MFAB iv TABLEOFFIGURESFigure1.Testconfigurationforthepairedcomparisonsideimpacttest....................................................2Figure2.Occupancyin15passengervan(4rowsofbenches)....................................................................4Figure3.Occupancyin12passengerMFAB(3rowsofdoubleseats).........................................................4Figure4.Approximatecameraplacement15passengervan(6).................................................................5Figure5.Approximatecameraplacementin12passengerMFAB(6).........................................................5Figure6.Sequenceofmotionofthetestandbulletvehiclesrecordedbyhighspeedvideocameras.......7Figure7.Timehistorytracesoftheaccelerationsrecordedineachtestvehicle........................................8Figure8.LocationofimpactpointandviewofimprintleftbytheF150ontheE350(left)andMFAB(right)............................................................................................................................................................9Figure9.ObliqueviewofintrusionobservedafterthetestsfortheE350(left)andMFAB(right).............9Figure10.OccupantseatingintheE350andMFABpriortothecrashtests.............................................10Figure11.RelativepositionsoftheheadandhiptargetsofthestrucksideoccupantswithrespecttobulletvehicleimpactfortheE350vanandMFAB......................................................................................10Figure12.ComparisonofinteriortrimandseatbeltanchoragesintheE350(left)andMFAB(right)......11Figure13.MotionduringthecrashoffrontrowoccupantsseatedintheE350(left)andMFAB(right)..12Figure14.MotionduringthecrashofthesecondrowoccupantsseatedintheE350(left)andMFAB(right)..........................................................................................................................................................13Figure15.PhotosoffinalrestingpositionoftheES2redummyfollowingthetest..................................15Figure16.MotionduringthecrashoftherearmostrowoccupantsseatedintheE350(left)andMFAB(right)..........................................................................................................................................................15Figure17.Photostakenafterthecrashoftherearmoststrucksidedummychestandsidestructures...16Figure18PhotosoffinalrestingpositionoffarsidedummyseatedinrearrowofE350(left)andMFAB(right)..........................................................................................................................................................17Figure19.ProfileoftheinteriortrimandwindowoftheE350van(black)andtheinteriorwalloftheMFAB(grey)................................................................................................................................................23 PAIREDCRASHTESTINGofa15PASSENGERVAN&MFAB v EXECUTIVESUMMARYInJanuary2008,eightpassengersdiedafterthe15passengervantheyweretravelling inwasstruck, at highway speed, by a tractortrailer near Bathurst, N.B.. On September 30, 2010,formerTransportCanadaMinisterStrahlcommittedthedepartmenttoconductacrashtestofa15passengervanasrequestedbyalobbygroupofconcernedcitizenswithastrongpersonalinterestinvanandbussafetyforstudenttransportation(www.vanangels.ca).Theobjectiveofthetestwastocomparetheprotectionavailabletorestrainedoccupantsofa15passenger van to that available to restrained occupants in an MFAB (MultiFunctionalActivityBus)inaseveresideimpactcrashtest.Theseverityofthetests,asdeterminedbythesizeandimpactspeedofthebulletvehicle,wassubstantiallygreaterthantheseverityofteststhat are conducted for regulatory compliance and consumer safety rating side impactprotectionprogramsworldwide.Amodelyear2011,Girardinmultifunctionalactivitybus(MFAB)andamodelyear2011FordE35015passengervanwereeach impactedat90degrees inthe leftrearaxlebya2009FordF150pickuptrucktravellingat75km/h.Therearaxleswereselectedasthelocationofimpacttoensurethatthestrikingbulletimpactedstructuralelementsthatwerecommontobothtestvehicles.Sevencrashtestdummieswereplacedonboardeachvehicleincomparableseatinglocations.The dummies were representative in size to mid size men and small women. All wereinstrumented with stateoftheart sensors in the head, chest and pelvis. All were seateduprightandallwere restrainedwith theavailable lapshoulder seatbelt.Themotionsof thedummiesduringthecrashwererecordedwithseveralhighspeedvideocameras.The injurymeasuresobtained from thedummies thatwere seatedon the struck sideof theE350weregenerallygreaterthanforthesamedummiesseatedintheMFAB.Twoofthethreedummyheadswereejected from thewindowof theE350whileonlyanarmof thedummyseatedintherearmostrowoftheMFABbrokethroughthewindow.The distance between the struck side dummies and the sidewalls influenced the injurymeasures. The interior trim profile of the E350 created an irregular profile and gapwhichallowedthedummytoaccelerateandpivot,priortostrikingtheadjacentwindow.IntheMFAB,thedummieswererestingagainsttheflatprofileofthesidewallimmediatelypriortothecrash.The outwardmotions of the headswere stopped by the rigid frames centered across eachwindowintheMFAB.Ina real collision, thepositionsof theoccupantsat themomentof impactdependon theirinitial posture and the vehicle manoeuvres that take place just prior to the impact. Anyhttp://www.vanangels.ca/PAIREDCRASHTESTINGofa15PASSENGERVAN&MFAB vi behaviourorvehiclemotionthatcausestheoccupantstodistancethemselvesfromthesurfacetheywilleventuallycollidewithduringthecrash,increasestheirriskofinjurybyallowingthemtoacceleratepriortohittingthesurface.Also, sincethewindowframes intheMFABarenotprotectedwith energy absorbingmaterials, the risk of injury to the head during a collisioninvolvinghumanoccupantscannotbediscounted.Allof thedummiesplaced across the aisle from the impactpoint inboth the E350 and theMFABslippedoutoftheshoulderbelts. IntheE350spacingbetweenadjacentoccupantswassufficientlyconstrainedsothatthefarsidedummiescollidedwiththestrucksidedummies.IntheMFABthesmallfemaledummieseitherslidintotheaisleorwerecatapultedintotheaisle.Themid sizemale dummy in theMFAB crossed the aisle and collidedwith the struck sidedummy.Thedummyresponsessuggestthatforhumanpassengersexposedtotheseconditionstherewouldbeariskofmoderatetosevereheadinjuryandariskofseriousseatbeltrelatedinjuriesforallthoseseatedonthefarsideoftheimpact,inbothstruckvehicles.The results of the paired crash tests are comparable to side impact testing of othermotorvehicles conducted by Transport Canada.As previouslymentioned, the severity of the testswassubstantiallygreaterthantheseverityofteststhatareconductedforregulatorycomplianceand consumer safety rating side impact protection programs. The effects on the dummyoccupantsweresignificantinbothcasesandsotherewillbenofurthertestingatmoresevereconditions.Aknowncountermeasurethatcanreducetheriskofhead injury forstrucksideoccupants isinflatable curtain technology. The countermeasures to limit occupant ejection from theshoulderportionoftheseatbeltandpreventsubsequentoccupanttooccupantcontact inalltypes of passenger vehicles are still under development. Potential candidatemeasuresmayincludeimproveddesignsofrestraintsandseatsandtheintroductionofinboardsideairbags.Aspartof itsregulatoryprogram,TransportCanadawillcontinuetoassesstheapplicabilityofcountermeasuresfortheprotectionofoccupantsof lightdutyvehicles ingeneral,duringsideimpact collisions. This will be undertaken in the context of the CanadaU.S. RegulatoryCooperation Council and the activities thereunder.PAIREDCRASHTESTINGofa15PASSENGERVAN&MFAB 1 INTRODUCTIONInJanuary2008,eightpassengersdiedafterthe15passengervantheyweretravelling inwasstruck, at highway speed, by a tractortrailer near Bathurst, N.B.. On September 30, 2010,formerTransportCanadaMinisterStrahlcommittedthedepartmenttoconductacrashtestofa15passenervanasrequestedbya lobbygroupofconcernedcitizenswithastrongpersonalinterestinvanandbussafetyforstudenttransportation(www.vanangels.ca).The 15passenger van is a preferred mode of transportation for a broad spectrum ofapplicationsandpassengertypes including;schooland/orsenioroutings,communityevents,andvariousshuttleservices.Analternativemodeoftransportationforschoolrelatedactivitiesisthemultifunctionalbus(MFAB).Thestructureofthesebusesissimilartothatofsmallschoolbusesexceptthattheyarenotequippedwithcertainsafetyfeaturesthatarerequiredforthesecure embarkation and disembarkation of school children, for example, stop lamps andextendablestopsigns.The intentionofthecrashworthinesstestingwasnottoreplicatethetragicBathurstcollision.Becauseofthehighspeedatwhichthecollisionoccurred(theclosingspeedwasestimatedbythecollisioninvestigatorsasbeingabout160km/h)andtheextremedifferenceinsizebetweenthestrikingtransporttruckandthe15passengervaninquestion(themassofthetruckatthetimeofimpactwasestimatedbytheinvestigatorstobemorethanfivetimesthatofthevan),thecrashwaslikely,fartoocatastrophic,foranyknowncrashworthinesscountermeasurestohaveprevented the lossof life.Theobjectiveof the testprogram therefore,was instead, tocompare the protection available to restrained occupants of a 15passenger van to thatavailable to restrainedoccupants in anMFAB in a severe side impact crash test involving abulletvehiclethatisrepresentativeofthetypethathastypicallybeenassociatedwithcausingserious injury inside impactcollisions inthefield. Thebulletvehicleswereofsimilarmasstoboth struck vehicles. These collisions nevertheless exceeded the severity of regulatorycomplianceandconsumerfocussedvehicleratingprogramsusedworldwide.Thisreportdescribesthetestmethodologyforthepairedtestprogram,presentstheresultsofthecrashtestsanddiscussestheimplicationsofthefindingswithrespecttopossiblecountermeasures. http://www.vanangels.ca/PAIREDCRASHTESTINGofa15PASSENGERVAN&MFABTESTMEHODOLOGYTestVehicles:1. 2011FORDE350van 15passengercapacity testmass:3382kg2. 2011GIRARDINMFAB 12passengercapacity testmass:3642kgStriking(Bullet)Vehicles:1. 2009FordF150 testmass:2814kg2. 2009FordF150 testmass:2813kgCrashConfiguration:The crash configuration consistedofaperpendicular impact (90degrees) into the stationarytestvehicle.Two identicalFordF150pickuptruckswereusedasbulletvehiclestostrikethesideofthestationaryE350vanandthestationaryGirardinMFABataspeedof75km/h.ThecenterofthefrontbumperoftheFordF150wasalignedtostriketheleftrearaxle(driverside)oftheE350,asshowninFigure1a&c;andtheleftrearaxle(driverside)oftheMFAB,showninFigure1b&d.Theimpactpointswereselectedtoensurecomparableimpactcharacteristics. 2 a) F150alignedwithE350vanimpactpoint b) F150alignedwithMFABimpactpointc) TopviewofF150alignmentwithE350 d) TopviewofF150alignmentwithMFABFigure1.Testconfigurationforthepairedcomparisonsideimpacttest.PAIREDCRASHTESTINGofa15PASSENGERVAN&MFAB 3 CrashTestDummiesandPlacementInTestVehicles:Atotalofsevenanthropomorphictestdummies(dummies)wereseatedandrestrainedbytheavailableseatbeltsineachofthetestvehicles.Thetypesofdummieswereasfollows:1. WS50thRibEye: Midsizemalewithmultipointopticalchestdeflectionmeasurements; 2. WS50thIRTRACC:Midsizemalewithuniaxialchestdeflectionmeasurements;3. ES2re: Midsizemalewithuniaxialchestdeflectionmeasurements;4. WS5thIRTRACC: Smallfemalewithuniaxialchestdeflectionmeasurements;5. WS5thIRTRACC: Smallfemalewithuniaxialchestdeflectionmeasurements;6. SIDIISRibEye: Smallfemalewithmultipointopticalchestdeflectionmeasurements;7. SIDIIS: Smallfemalewithuniaxialchestdeflectionmeasurements;TheWorldSID (WS) dummies are newly developedworld harmonized side impact dummies.There are 25midsizemale (WS 50th) and only 7 small femaleWorldSID dummies (WS 5th)currently inuseby governments and industry researchprograms inAsiaPacific, Europe andNorthAmerica.Thesedummies represent the latest stateof theart technologyavailable forside impact crashworthiness evaluation. The ES2re and SIDIIs are the dummies that arepresently used for side impact regulatory testing by the National Highway Traffic SafetyAdministration (NHTSA) intheUnitedStates.Sevencrashtestdummies wereseated ineachtestvehicle.The seating locations, identified in Figure 2 and Figure 3, were selected to optimize thecomparisonbetweenthetwotestvehicletypes.Forexample,theleftsidewasselectedasthestrucksidebecausethereisagapbetweentheendofthebenchseatandthesidewallontherightsideofthe15passengervanthatisnotpresentintheMFAB.Allcrashtestdummieswererestrainedwiththeavailable lapandtorsobeltsoftherespectivevehicles.Duetothe limitednumber of available dummies, the driver seatwas not occupied. Occupant protectionwasevaluatedonlyforthepassengersseatedintherear.TheseatinglocationforeachdummyisidentifiedinFigure2andFigure3.Thelayoutisshownin table format for illustrative purposes only and is not to scale. The 15passenger vanillustrated in Figure 2 contains four rows of bench seats equippedwith threepoint lap andtorso belts. The three darkened columns represent spacing between the seats; the seatinglocationsareseparatedbythedottedlines.Thereardoorsarelocatedontherightsideofthe15passengervanadjacenttotheaisle,which isrepresentedbythedarkenedrow,abovethefirstthreerowsofbenchseats.TheMFABlayoutshowninFigure3consistsofthreerowsofdoubleseatsequippedwiththreepointlapandtorsobelts.ThedarkestcolouredcolumntotheleftisanuprightpaddedbarrierPAIREDCRASHTESTINGofa15PASSENGERVAN&MFABlocatedjustaheadofthefrontrow.Theshadedrowpassingthroughthecenterrepresentstheaisle. WS5th WS5th ES2re SIDIIs SIDIIsRibEyeWS50thRibEyeWS50thFigure2.Occupancyin15passengervan(4rowsofbenches) WS5thWS5th ES2re SIDIIsSIDIIsRibEyeWS50thRibEyeWS50thFigure3.Occupancyin12passengerMFAB(3rowsofdoubleseats)CAMERASandPLACEMENT:Theoccupantmotionandinteractionwiththevehicleinteriorandwithotheroccupantsduringthecrasheventwererecordedwithsixonboardhighspeedcameras.Theframeratesforthecameraswerebetween500and1000frames/sdependingontheluminosityachievedaboardthebus.ThewindowsintheMFABwereleftopentoimproveinteriorluminosity. 4 Theinteractionsbetweenthetwovehicleswererecordedwithsixhighspeedcameraslocatedonthecrashpadandabovethecrashpadtoprovidemultipleviewsoftheevent.Exteriorhighspeedcamerasrecordedtheeventsat1000frames/s.Twostandardvideocamerasrecordedthecrasheventinrealtimefromtwoexteriorviews.PAIREDCRASHTESTINGofa15PASSENGERVAN&MFAB Smallfemale Smallfemale Midsizemale Smallfemale SmallfemaleMidsizemaleMidsizemaleFigure4.Approximatecameraplacementin15passengervan(6) SmallfemaleSmallfemaleMidsizemale SmallfemaleSmallfemaleMidsizemaleMidsizemaleFigure5.Approximatecameraplacementin12passengerMFAB(6)InstrumentationTriaxialaccelerometerswereinstalledattheapproximatecenterofgravityofthetestvehicles.Allcrashtestdummieswereinstrumentedwithaccelerometersinthehead,chestandpelvis,andloadcellsintheneck,lowerspineandpelvis.TwooftheWSdummieswereequippedwithrotationalaccelerometersinthehead.Inadditiontothestandarddummyinstrumentation,anopticalmultipointchestdeflectionsensingdevice(RibEye)wasinstalledinonesmallfemaledummy(SIDIIs)andinoneaveragesizemaledummy(WS50th).TheprocessingofthedatawascarriedoutfollowingtheprotocolsestablishedbytheSocietyofAutomotiveEngineers(SAEJ211). 5 Thepositionsofthedummyheadswererecordedbyusinga3DFaroarm.ThepointoforiginforallmeasurementswaslocatedatthecenterofthefrontbumperatgroundlevelforeachoftheE350andtheMFAB.Headtargetlocationswererecordedforthepassengersinbothvehicles.HiptargetswerenotobtainedintheMFABduetospaceandrestraintconstraints.ThehiplocationsintheMFABwereestimatedonthebasisofdummyposture.PAIREDCRASHTESTINGofa15PASSENGERVAN&MFABRESULTSVehicleKinematicsTheF150bulletvehiclesstruckthedesignatedimpactpointabovetheleftrearaxleoftheE350ataspeedof75.36km/handabove the leftrearaxleof theMFABataspeedof75.6km/h.Figure6,showsfreezeframesobtainedfromthehighspeedvideosto illustratethemotionofeachvehicle. InFigure6athebulletvehiclehas impactedthesidestructureoftheE350.Thefrontendofthepickuphasdeformedandispushingthevanalongitspathtowardsthetopofthe image.Thearrowpointstothesidewindowsofthevanastheyarebeingblownoutandthecircleidentifiestherightrearwheelthatisbeingdisplacedoutward.InFigure6btheMFABisalsobeingpushedalongthepathofthebulletvehiclebutthewindowsarestillintactandtheright rearwheel is not visible. Both the E350 andMFAB remained engagedwith the bulletvehicleforadistanceofseveralmeterspriortorotatingcounterclockwise,outofthepathofthebulletvehicle(Figure6c&d). 6 a) ImpactofF150intotherearaxleofE350 b) ImpactofF150intorearaxleofMFABc) CounterclockwisemotionofE350at238ms d) CounterclockwisemotionofMFABat238msPAIREDCRASHTESTINGofa15PASSENGERVAN&MFABe) SideviewoftheE350motionat238ms f) SideviewoftheMFABmotionat238msg) RotationofE350istemporarilyhalted. h) RotationoftheMFABistemporarilyhalted.Figure6.Sequenceofmotionofthetestandbulletvehiclesrecordedbyhighspeedvideocameras.Figure6c isa freeze frameobtainedas theE350begins to rotateaway from thepathof thepickuptruck.TheredcircleidentifiestheejectionoftheheadanduppertorsooftheWSmaledummythatwasseated intherearmostrowonthestrucksideofthevan.Theorangecirclehighlights theejectionof theheadand left shoulderof theWSRibEyedummy seated in themiddlerowonthestrucksideofthevan.Figure6disafreezeframeoftheMFABobtainedatthesamemomentintimeasthatshownin6c.Theredcircleindicatesthelocationwherethedummyarmwasejectedthroughthewindow. Figure6eand6fpresentthesideviewofthemotionatthesameinstantintimeshowninFigure6candd.BoththeE350andtheMFABtiptowardstherespectivebulletvehicle. 7 Thecounterclockwisemotionistemporarilyinterruptedbythebodyofthepickuptruck.Thetwovehiclesbecomealignedalongtheirlongitudinalaxis(Figure6g&h).Eachtestvehiclecontinuesitsrotationtothefinalrestingpointasthebulletcontinuesitsforwardtrajectory.PAIREDCRASHTESTINGofa15PASSENGERVAN&MFABTheaccelerometersmountedtothecenterofgravityofeachtestvehiclerecordedsimilarpeaklateralaccelerations.ThetopgraphshowninFigure7ashowsthatthepeaklateralaccelerationfortheE350showninbluewas24.7goccurringat35.1mswhilethepeaklateralaccelerationfortheMFAB,showninredwas25.6goccurringat33.4ms.Bothaccelerationtracesindicateveryrapidonsetsof lateralaccelerationwiththepeaksoccurringwithinthefirst35msoftheimpact.TheMFABappearstohaveexperiencedalongersustainedlateralaccelerationthantheE350.Figure7billustratestheverticalcomponentoftheaccelerationrecordedatthecenterofgravityof the test vehicles.TheMFAB shownby the red traceappears tohaveexperiencedslightlygreaterverticalimpulsethantheE350.a) Timehistoryoflateralaccelerationrecordedatthecenterofgravityofthetestvehiclesb) Timehistoryoftheverticalaccelerationrecordedatthecenterofgravityofthetestvehicles 8 MFABE350MFABE350Figure7.Timehistorytracesoftheaccelerationsrecordedineachtestvehicle. PAIREDCRASHTESTINGofa15PASSENGERVAN&MFABVehicleIntrusionFigure8and9presentthelocationoftheimpactpointandtheintrusionthatresultedfromthecollisionwiththeE350andtheMFAB.Theintrusionwaslimitedtotheareasurroundingtheleftrearwheels inbothtestvehicles.There issomewhatmoredeformationobserved intheE350thanintheMFAB.Note that theheightof thewindowopenings issimilar inboth theE350and theMFAB.Twoprincipaldifferencesarethesizesofthewindowopeningsandtheframes.TheE350windows,locatedoverthewheelarewiderthanintheMFABandcannotbeopened.ThewindowsintheMFAB consistof two sections that slide vertically toopen.Thewindowedgeactsasa crossmemberthatextendshorizontallyacrosseachwindow.Theeffectthatthesewindowdesignshave on occupant kinematicswill be discussed in the section describing the results of theoccupantkinematics.Figure8.LocationofimpactpointandviewofimprintleftbytheF150ontheE350(left)andMFAB(right).Figure9.ObliqueviewofintrusionobservedafterthetestsfortheE350(left)andMFAB(right). 9 PAIREDCRASHTESTINGofa15PASSENGERVAN&MFABOccupantKinematicsThereweresevencrashtestdummiesrestrainedwiththevehicleseatbeltsineachtestvehicle.Threedummieswereseatedonthestruckside,threedummieswereseatedonthenonstrucksideandonewasseated intherearmostrowadjacenttothestrucksideoccupant.Figure10displaystheinteriorphotostakenfromthefrontoftheE350andMFABpriortothecrashtests.Figure10.OccupantseatingintheE350andMFABpriortothecrashtests.02004006008001000120014001600180020003000 3500 4000 4500 5000 5500 6000VERTICALDISTANCE(mm)HORIZONTALDISTANCE(mm)headtargetE350VAN HeadtargetMFABE350VANHpoint MFABHpointF150bumperwidthalignedwithE350 F150bumperwidthalignedwithMFABF150longitudinals/E350 F150longitudinals/MFABFigure11.RelativepositionsoftheheadandhiptargetsofthestrucksideoccupantswithrespecttobulletvehicleimpactfortheE350vanandMFAB. 10 Figure 11 is a plot documenting the dummy head and hip locations relative to the bulletvehicles.Theheadandhiptarget locationsfortheoccupantsseatedonthestrucksideoftheE350 van are represented by the solid blue circles and solid blue triangles respectively andPAIREDCRASHTESTINGofa15PASSENGERVAN&MFABrepresentactualmeasurements.ThesolidredcirclesaremeasuredvaluesfortheheadtargetsofthestrucksideoccupantsintheMFAB,whiletheredtrianglesareestimatesofthehippointlocations.Thecoordinateslocatedatthebottomofthegraphrepresenttherelativelocationoftheimpactingbulletvehicles.ThetwoblueoutlinedcirclesrefertotheouterlimitsoftheF150bumperthatstrucktheE350whilstthetworedoutlinedcirclesrefertotheouterlimitsoftheF150bumperthatstrucktheMFAB.TheblueandredsquaresrefertothelocationsoftheF150longitudinalmembersoftheE350andMFAB,respectively.ThestarsrefertothecenterpointsofeachstrikingF150bumper.Generally, the dummy placement in theMFABwasmore spread out than in the E350. Thedummies intheMFABareseated further forwardrelativetothe frontendoftheF150whencomparedtotherelativepositionsofthedummiesintheE350.Thestrucksidedummiesseatedin theMFABwere located further forward than the dummies seated in the E350with thegreatestdifferencebeingobservedbetweenthetwoforemostoccupants. Infact,theheadoftheforemostoccupantintheMFABwaslocatedapproximately535mmforwardofthecloseststriking longitudinalwhereas thehead of the dummy seated in the E350was only 114mmforwardofthestrikinglongitudinal.Thedistancebetweendummyoccupantsofthesamerowwasalsogreater in theMFAB.Forexample, thedistancebetween thehead targetswereonaverage,500mmgreaterintheMFABthanintheE350.TheinteriorprofilesofthestrucksidewallsweredifferentintheE350andtheMFAB.Figure12isafrontviewoftheoccupantseatedinthesecondrow.TheE350hasasteppedinteriorplastictrimwhichextendstotheupperchest,belowtheaxilla(underarm)ofthe50thmaledummy;theMFABhasnointeriortrim;theflatwallextendstothelowerwindowframe.IntheleftsidephotoofFigure12,thereisagapbetweentheshoulderandthewindowintheE350whereasthe dummy shoulder is in full contactwith thewindow of theMFAB seen in the right sidephoto.TheupperbeltanchorsaremountedinthepillaroftheE350butintegratedintheseatoftheMFAB. 11 Figure12.ComparisonofinteriortrimandseatbeltanchoragesintheE350(left)andMFAB(right).PAIREDCRASHTESTINGofa15PASSENGERVAN&MFABThemotionof thedummieswillbedescribedbypresentingasequenceof twovideo imagescapturedatthemomentofimpactandapproximately100mslaterinthecrashevent.Thetwoimages are shown for the E350on the left and for theMFABon the right, for each rowofoccupants. The imagesbeginwiththe frontrowandprogressrearward inFigure13throughFigure16.Descriptionsoftheobservedmotionfolloweachfigure.Frontrowkinematics:a) Strucksidedummystrikeswindow b) Strucksidedummystrikeswindowframec) Occupanttooccupantcontact d) FarsidedummyslidesoffseatFigure13.MotionduringthecrashoffrontrowoccupantsseatedintheE350(left)andMFAB(right)The front row contained two dummies representing smallwomen, struck side SID IIs, nonstrucksideWS5th.TheheadofthestrucksidedummyintheE350showninFigure13aandcfirststrikes thewindow then rolls forward from left to rightstriking the forwardpillarof thewindow.Thethoraxandpelvisareinfullcontactwiththeinteriortrimastheuppertorsopivotsaboutthewindowframe.Basedonthekinematicsobserved,thereisapotentialforheadandfacial injuriesaswellas chestandpelvic injuries.Chest injuriesmaybe compoundedby theoccupanttooccupantcontact. 12 PAIREDCRASHTESTINGofa15PASSENGERVAN&MFABTheheadofthestrucksidedummyintheMFABshowninFigure13banddstrikesthewindowframethat isadjacenttoherseatingposition.Theshoulderandarmcomplex issupportedbythe sidewall; this eliminates outward rotation and appears to reduce the contactwith thethorax.Thekinematicssuggestapotentialforheadandfacialinjuries.ThefarsidedummyintheE350isprojectedlaterallyalongthebench,flexesovertheseatbeltand collideswith the struck side occupant. The seat beltmigrates and penetrates into theabdominalregionastheWS5thdummyheadimpactsthestrucksidedummy.Thereispotentialforseriousabdominal injuryand lowerribfracturesfrom interactionwiththeseatbelt.Theremayalsobepotentialforheadinjuryresultingfromthecollisionwiththeotheroccupant.ThefarsidedummyintheMFABisprojectedlaterally,offtheseatandissuspendedbytheseatbelt.There ispotential for seriousabdominal injuryand lower rib fractures from interactionwiththeseatbelt.Secondrowkinematics: 13 a) WSdummyheadisejectedthroughthewindow,dummiescollideb) WSdummystrikesthewindowframec) NonstrucksidedummypivotsstrikesWSdummyandlosesheadskind) Nonstrucksidedummypivotsandstrikesstrucksidedummy.Figure14.MotionduringthecrashofthesecondrowoccupantsseatedintheE350(left)andMFAB(right)PAIREDCRASHTESTINGofa15PASSENGERVAN&MFAB 14 Twodummiesrepresentingaveragesizedmenareseatedinthesecondormiddlerow.OnthestrucksideistheWS50th,onthefarornonstrucksideistheES2re.IntheE350,theheadoftheWS50th isejected through thewindowand strikes the crumpledhoodof theF150.Thelettering that is seenbeneath thedummyhead inFigure14a is thePMGTechnologies labelaffixedtothehoodclosesttothewindshield(seeFigure6a).Theshoulderbeltistwistingandpenetratingintotheneck.Theshoulderappearstobelodgedbetweenthecrumplinghoodandthewindow frameofthevan,whilethethorax is in fullcontactwiththetrimanddeformingsidepanel.ThekinematicsoftheWS50thsuggestahighriskofheadandfacial injuries.Chestinjuriesintheformofmultipleribfracturespossiblyaccompaniedbyinternalorgantraumaarelikely.Chestandorganinjurieswouldbecompoundedbytheoccupanttooccupantinteraction.TheheadoftheWS50th intheMFABstrikesthewindow frame.Thisrigidstructurepreventsthe ejection of the dummy head. The shoulder belt penetrates into the neck region. Theshoulder is supportedby thewindowand thusappears toactasablockerpreventingdirectimpact to the thorax. The right side of theWS 50th is struck by the head of the far sideoccupant.Thereispotentialforheadinjurycausedbytheimpactwiththewindowframe.Chestandinternalorgantraumamayresultfromtheimpactwiththeotheroccupant.TheES2relocatedonthenonstrucksideoftheE350vanisprojectedlaterallyintothestrucksidepassenger.Thedummyslipsoutoftheshoulderbeltearly intheeventandpivotsaboutthe lapandshoulderbelt.Theseatbeltpenetrates into theabdominalcavitywhile theheadcollides with the lower thorax of theWS 50th. The flesh skin of the dummy is dislodged.Expectedinjuriesresultingfromtheobservedkinematicsincludeheadinjury,ribfracturesandinternalorganinjury.TheES2reseatedintheMFABdisplayssimilarkinematics.Thedummytranslateslaterally,offtheseat then rotatesabout theseatbeltandstrikes theWS50thwithhishead.The lapandshoulderbeltpenetratesdeeplybetweenthepelvisand lowerribs.Expected injuriesresultingfromtheobservedkinematicswouldincludeheadinjury,ribfracturesandinternalorganinjury.ThefinalpositionsoftheES2reintheE350vanandtheMFAB,asshowninFigure15arequitesimilar.PAIREDCRASHTESTINGofa15PASSENGERVAN&MFAB 15 a) NonstrucksidedummyinE350posttest b) NonstrucksidedummyinMFABposttestFigure15.PhotosoffinalrestingpositionoftheES2redummyfollowingthetest.Thirdrowkinematics:a) MotionofthreerearmostoccupantsoftheE350atimpactb) MotionofthethreerearmostoccupantsoftheMFABatimpactc) Ejectionofstrucksidedummyhead d) Impactofhead&chestintowindowframeFigure16.MotionduringthecrashoftherearmostrowoccupantsseatedintheE350(left)andMFAB(right)PAIREDCRASHTESTINGofa15PASSENGERVAN&MFABThreedummiesrepresentingoneaveragesizedmaleandtwosmallwomenwerepositionedinthefinalrow. TheSIDIIsshown inbluewasadjacenttothestrucksideWS50th. TheWS5thwasseatedinrightoutboardpositiononthenonstruckside.At impact,theheadoftheWS50thseatedonthestrucksideoftheE350 isprojected intotherearwindow.AscanbeseenintheupperrightcorneroftheimageinFigure16a,theheadoftheWS 50th strikes the upperwindow edge as it is ejected through the backwindow. Thedummypivotsaboutthebottomwindowedge,suchthatboththeheadand leftshoulderareoutside thevehicle.Theheadcanalsobe seen from theexterior.The redcircle inFigure6chighlights theejectedheadas thevehiclebegan itscounterclockwise rotation.Theshoulderbelt,whiletautagainsttheneck is ineffectiveatrestrainingtheuppertorso.Thechestmakesfullcontactwiththeinteriortrimandsidestructureofthevan.ThiscanbebettervisualizedintheposttestphotosshowninFigure17.Thekinematicsofthisoccupantsuggestthatthereisahighriskofhead injury,riskof lacerationtotheheadandneckaswellasanelevatedriskoforgantrauma,chestandupperextremityinjury. 16 a) Chestcontactwithtrim&sidestructureinE350 b) ExposedsideedgeinMFABFigure17.Photostakenafterthecrashoftherearmoststrucksidedummychestandsidestructures.TheheadoftheWS50thseatedintheMFABstruckthewindowframecrossmemberatimpactasshowninFigure16b.InFigure16donecanobservethedistortionofthewindowframeandthe impactof thedummy shoulder and arm shattering thewindows.Contactwasobservedbetween thechestof thedummyand the loweredgeof thewindow. Impactoccurredatanangle.Thestandard twodimensionaldummyrib instrumentationcontained in thisversionoftheWS50thcannotdeflect in thisdirection.Ascanbeseen inFigure17babove, thebottomedgeofthewindowintheMFABisunprotectedandcontainsahandletoreleasethewindowinemergencysituations. Thekinematicsforthisoccupant indicatethattherewouldbeariskofhead injury, a risk of head and/or neck lacerations and a possibility of chest and or organtrauma. Upper extremity injuries involving fractures and/ or lacerations to the arm andshouldermayoccur.PAIREDCRASHTESTINGofa15PASSENGERVAN&MFABTheadjacentoccupantseatedintheE350collideswiththestrucksideoccupantandisstruckbythefarsideoccupant.ThereisarathersevereimpactbetweentheheadofthefarsidefemaleandthechestoftheSIDIIs.Witnessmarks,identifiedbytheyellowsmearonthebluejacketareseeninFigure16c.Theinjuryriskforthisdummymayincludetheheadandwouldverylikelyinvolvethechest.TheadjacentoccupantseatedintheMFABcollideswiththestrucksideoccupantbutisnotstruckbythefarsideoccupant.TheSIDIIsappearstobeshieldedfromtheimpactforcesbythelargerdummyseatedonthestruckside.Theremaybeariskofheadinjuryfromcontactwiththestrucksideoccupant.InboththeE350andtheMFABthefarsideoccupantisnoteffectivelyrestrainedbythelapandshoulderbelt.Inbothcrashesthedummyisobservedtoslipoutofthebeltassheisprojectedtowardstheimpactzone.ThedummyrotatesabouttheseatbeltstrikingthechestoftheSIDIIsin thecaseof theE350. Ifone lookscloselyat the images inFigure16c&d it ispossible toobserve theextremepenetrationof the seatbelt into theabdominalcavity. In fact, the twocrash tests severed the dummy lower spine. In theMFAB she cannot reach the SIDIIs butessentiallyendsupwithherheadon the floorbetween the seatsas shown in thepost testphotosbelowinFigure18.Inbothvehiclesthereishighriskofheadinjury,ahighriskofchestfracturesandinternalorganinjuryaswellapotentialforlowerspineinjuries.Figure18PhotosoffinalrestingpositionoffarsidedummyseatedinrearrowofE350(left)andMFAB(right). 17 Table1presentsasummaryofthepotentialfor injuryforeachoccupantthat isbasedonthekinematicanalysispresented.Itisimportanttonotethatthekinematicanalysiscannotbeusedtoquantify thedegreeof risk. Forexample, in the caseofahead impactwe recognize thatthere isariskof injurybutwecannotforexample,readilydiscriminatebetweena10%riskofseriousinjuryanda50%riskofseriousinjury.Theredshadedboxesinthetableserveasflagstosignalthepotentialfor injury.Basedonthis initialoverviewthe injurypotentialappearstobecomparableforbothvehicles.PAIREDCRASHTESTINGofa15PASSENGERVAN&MFAB 18 Thenextstep istousethisanalysisinconjunctionwith injuryresponsemeasuresrecordedbytheonboarddummyinstrumentationtoconfirmthevalidityofmeasuredresponsesanddefinetherisks.Sinceeventhelateststateoftheartdummiescannotdetectallsourcesofinjurywerely on available measures, the kinematic response and best engineering judgement todetermineacomprehensiveassessmentofprotection.Table1.Summaryofinjurypotentialbasedonkinematicanalysis STRUCKSIDE NONSTRUCKSIDELOCATION DUMMY BODYREGION E350 MFAB DUMMY BODYREGION E350 MFABROW1SIDIIs HEAD WS5th HEAD NECK NECK CHEST * CHEST ORGAN ORGAN UPPEREXT. UPPEREXT. SPINE SPINE LACERATION facial facial LACERATION ROW2WS50th HEAD ejection ES2re HEAD NECK ejection NECK CHEST * * CHEST ORGAN * * ORGAN UPPEREXT. UPPEREXT. SPINE SPINE LACERATION facial head LACERATION ROW3WS50th HEAD ejection SIDIIs HEAD NECK ejection NECK CHEST CHEST *ORGAN ORGAN *UPPEREXT. UPPEREXT. SPINE SPINE LACERATION face/neckhead/neckLACERATION WS5th HEAD LEGEND NECK IMPACTwithinteriorofvehicle CHEST EJECTIONfromwindow ejection ORGAN IMPACTwithadjacentoccupant UPPEREXT. CONTACTwithexposedsurface SPINE STRUCKbyfarsideoccupant * LACERATION PAIREDCRASHTESTINGofa15PASSENGERVAN&MFAB 19 InjuryMeasuresInjury risk is estimated by comparing measured values obtained from the dummyinstrumentation to established injury reference values or injury risk curves. Injury referencevalues are generallydevelopedby subjecting a smallnumberof cadavers toprescribed testconditionsandcomparingthemeasuredresponsestothoseofadummyexposedtothesametest conditions. Since cadaverdataare rareand costly toobtain, thedataarequite limited.Injury reference values are available only for certain body regions and are valid for only alimited number of injurymechanisms. The resulting estimate of risk remains just that, anestimatewithawidemarginoferror.Thecurrentregulatorydummies,ES2reandSIDIIshaveestablishedinjuryreferencevaluesforthebodyregionsthataremandatedbytheregulation,forexamplethehead,chestandpelvis.ThenewlycreatedWorldSID50thhasproposedvaluesforthehead,neck,chest,pelvisandlegs,thoughthestatisticalmethodsusedtodefinetheriskcurveshaveyettobefinalized.TheinjuryreferencevaluesfortheWS5thhavenotbeendeveloped,sowhileanestimateofriskcannotbeestablishedatthistime,itisneverthelesspossible,tocompareresponsesandevaluatetherelativeseverityofanimpact.Afinalnoteofcautionisofferedontheorientationoftheinstrumentationwithinthedummies.With the possible exception of multiaxial accelerometers most sensors in a dummy aredesigned and aligned tomeasure in themost likelydirectionof impact. Since a side impactdummyisalmostalwaysseateduprightinatestvehiclethesensorsarecalibratedtomeasureperpendicular impacts.Thecapabilitytomeasureoblique loading isnotpossible ineithertheES2re or the SIDIIs due to themechanical design of the ribs. TheWorldSID dummies aremechanicallycapablebutthesensorstomeasureobliqueandotheroutofplanemotionsarestill under development. Therefore, in a severe collision such as the E350 andMFAB, thedirection of force may not be detectable. Specifically, there are no sensors capable ofaccuratelytrackingtheimpactexposureforthenonstruckdummyasthedummytumblesoutoftheseattowardsthefloor.Table2, summarizes the injury responses. Shaded cells represent injury responses forwhichthereareknown injuryriskvalues.Theredshadedcellsrefertoanominal25%riskofsevereinjury(AIS4+),theblueshadedboxesrefertoanominal25%riskofseriousinjury(AIS3+)andtheyellowboxesrefertoanominal25%riskofamoderateinjury(AIS2+).Severityofinjuryisdescribedby theAbbreviated Injury Scale (AIS) and represents the 'threat to life' associatedwith the injury. Injuries are ranked from 1 to 6,where 1 is consideredminor and 6 is notsurvivable.The scale isnotameasureofdisability.Thereforeamoderate injury to theheadwhichisanAIS2canhaveseriouslongtermconsequencesthatarenotreflectedinthethreattolife.PAIREDCRASHTESTINGofa15PASSENGERVAN&MFAB 20 Table2:Summaryofinjurymeasuresandinjuryriskswhereapplicable. STRUCKSIDE NONSTRUCKSIDELOCATION DUMMY BODYREGION E350 MFAB DUMMY BODYREGION E350 MFABROW1SIDIIs HEADpeakg1 74 66 WS5th HEADpeakg 140 70HIC36 405 270 HIC36 1793 520NECKforce 1631 1075 NECKforce 1666 1183THORAXDy 46 THORAXDy 7 41T1g 46 27 T1g 42 66T12g 1442 31 T12g 35 51PELVISforce 6080 2456 PELVISforce 463 837PELVISpeakg 100 27 PELVISpeakg 47 43ROW2WS50th HEADpeakg 77 65 ES2re HEADpeakg 204 144HIC36 578 343 HIC36 7524 2486NECKforce 2908 1143 NECKforce 4025 2947THORAXDy THORAXDy T1g 35 28 T1g 43 35T12g 54 45 T12g 44 53PELVISforce 1745 880 PELVISforce 6120 4267PELVISpeakg 75 47 PELVISpeakg 60 73ROW3WS50th HEADpeakg 162 71 SIDIIs HEADpeakg 120 74HIC36 1604 519 HIC36 3285 678NECKforce 3080 2282 NECKforce 4168 2203THORAXDy 56 42 THORAXDy T1g 88 40 T1g 108 53T12g 69 45 T12g 3222 55PELVISforce 1400 974 PELVISforce 72742 4175PELVISpeakg 104 48* PELVISpeakg 81 50 WS5th HEADpeakg 115 75HIC36 >2000 974NECKforce 5427 2595LEGEND NECKMx/My 36/104 44/33SEVERE THORAXDy SERIOUS T1g 161 58MODERATE T12g 78 435%Moderate * PELVISforce DL 347DATA OSSL PELVISpeakg 79 54 1Peakresultantheadacceleration3msclip2CausedbycollisionwithotheroccupantPAIREDCRASHTESTINGofa15PASSENGERVAN&MFAB 21 StrucksideOccupantsFrontRowThepeakresultantheadacceleration(3msclip)andtheheadinjurycriterion(HIC)forthesmallfemaledummyseatedinthefirstrowwerebelowthelevelsnormallyassociatedwithariskofinjurytothehead.TheSIDIIsheadresponsesrecorded inboththeE350andtheMFABwerebelow the regulatory injury threshold levels. The chest deflection and pelvic accelerationresponsesfortheSIDIIsseatedintheE350indicatea25%riskofmoderateinjury.Theseinjuriesmight include forexample,oneor two rib fractures and apelvic fracture.TheT12or lowerspineaccelerationresponse is indicativeofa25%riskofseverethoracicorabdominaltraumaforthedummyseated intheE350anda25%riskofseriousthoracicorabdominaltraumaforthedummyseatedintheMFAB.TheelevatedspinalaccelerationswerecausedbytheheadofthefarsideoccupantcollidingwiththechestoftheSIDIIsinboththeE350andMFABtests.MiddlerowThepeakresultantheadacceleration(3msclip)andtheheadinjurycriterion(HIC)forthemidsizemaledummyseatedinthesecondrowsuggestariskofmoderateinjurytotheheadfortheWS50thseated intheE350. IntheMFAB,theWS50thheadstruckanddeformedthewindowframebutwascontainedwithinthevehicle;theheadinjuryassessmentvalueswerelow.Theriskofribfracturescouldnotbeassessedineithertestvehicleduetodataloss.ThepelvicresponseofthedummyseatedintheE350suggestsariskofmoderateinjuryorfracturetothepelvis.RearmostrowThepeakresultantheadacceleration(3msclip)andtheheadinjurycriterion(HIC)forthemidsizemaledummyseatedinthethirdorrearmostrowsuggestariskofsevereinjurytotheheadfortheWS50thseated intheE350. IntheMFAB,theWS50thheadstruckanddeformedthewindowframebutwascontainedwithinthevehicle;therewasariskofmoderateheadinjuryforthisseatingpositionintheMFAB.The deflectionsmeasured in the chest suggest a risk of serious injury (three ormore ribfractures) for theWS seated in the E350 and a risk ofmoderate injury (two ormore ribfractures) for theWS seated in theMFAB. Peak resultant acceleration clips obtained at theupper(T1)andlowerspine(T12)arequiteelevatedfortheWSseatedintheE350comparedtotheMFAB.Whilenodefinitive risk curveshavebeendefined thismagnitudeof accelerationcould lead to serious thoracic or internal organ injuries. Finally, the elevated peak resultantaccelerationsrecorded inthepelvisoftheWSseated intheE350areconsistentwithariskoffractureormoderateinjury.PAIREDCRASHTESTINGofa15PASSENGERVAN&MFAB 22 Farside(nonstruck)OccupantsFrontRowThepeakresultantheadacceleration(3msclip)andtheheadinjurycriterion(HIC)forthesmallfemaledummyseatedinthefirstrowsuggestariskofsevereheadinjuryintheE350andmoderateinjuryintheMFAB.Theupperandlowerspineaccelerations(T1andT12)wereelevatedfortheWS5thseatedintheMFAB.However,sinceinjuryriskassessmentthresholdshavenotbeendevelopedforthisdummyitisnotpossibletoestimatethelikelyseverityofinjuryatthistime.MiddlerowThepeakresultantheadacceleration(3msclip)andtheheadinjurycriterion(HIC)forthemidsizemaledummyseated inthesecondrowsuggestariskofsevere injurytotheheadfortheES2reseatedintheE350andseatedintheMFAB.Theneckresponsespointtoariskofsevereneck injury, possibly involving neurological injury, for the ES2re seated in the E350 and amoderateneckinjury,possiblyinvolvingvertebralfracture,forthedummyseatedintheMFAB.The upper and lower spine accelerations are indicative of serious chest and or abdominaltrauma forboth thedummies in theE350andMFAB.There isalsoa riskofmoderate injury(fracture,forexample)tothepelvis.RearmostrowThepeakresultantheadacceleration(3msclip)andtheheadinjurycriterion(HIC)forthesmallfemale dummy seated in the middle seat position adjacent to the struck side male, areconsistentwithariskofsevereheadinjuryintheE350andmoderateheadinjuryintheMFAB.Theneckforcesrecorded intheSIDIIsrepresentariskofsevereneck injurywithneurologicalinjuryforthedummyseated intheE350andariskofseriousneck injuryalso involvingsomeneurologicaltraumaforthedummyseatedintheMFAB.Elevated spinal accelerations and high pelvic forces resulting from impactwith the adjacentdummiescouldcauseseverethoracicandorabdominaltraumaandpelvicinjuryforthedummyseated in theE350.Whilenotnegligible, theaccelerationsandpelvic forces recorded in theSIDIIsseatedintheMFAB,wereneverthelessbelowtheregulatoryinjurythreshold.TheWS5thseatedintheoutboardlocationhadheadresponsesthatwereconsistentwithariskof severe head injury in the E350 and serious head injury in theMFAB. Since injury riskassessmentthresholdshavenotbeendevelopedforthisdummy it isnotpossibletoestimatethelikelyseverityofinjuryatthistime.PAIREDCRASHTESTINGofa15PASSENGERVAN&MFABDISCUSSIONStrucksideOccupantsEffectoftheinteriortrimonloadingexposureandinjuryriskFigure19comparestheinteriortrimoftheE350vantothesidewallsoftheMFABwithrespecttotheoutboardstrucksidedummyprofile.Thetwoprofilesareverydifferent.ThesidewallsoftheE350illustratedbytheblacklinearecoveredwithaplastictrim.Thetrimextendsinboard,approximately 120mm from the bottom of thewindow and forms two stepped horizontalsurfaces,eachapproximately60mmwide.The lowerhorizontal surfaceor ledgeappears toserveasanarmrest.Thewindow,alsoshowninblackhasaslightcurvaturewithanupperedgethatisinlinewiththelowerinteriortrim.TheinterioroftheMFABillustratedbythegreylineisaflatwallwithnointeriortrim.Thewindowsarealmostvertical.10001100120013001400150016001700180019002000100 200 300 400 500 600 700 800 900 1000 1100headshoulderhipE350windowMFABwindow frame 23 Figure19.ProfileoftheinteriortrimandwindowoftheE350van(black)andtheinteriorwalloftheMFAB(grey).PAIREDCRASHTESTINGofa15PASSENGERVAN&MFAB 24 Ofsignificance intheoutlineviewsshownabove isthedistancebetweentheoutboardstrucksidepassenger,outlinedinblueandthetrimorsidewalloftherespectivevehicles.Thegreaterthedistancebetweenanoccupantandtheinteriorsurface,thegreaterthevelocitywithwhichthebodyoftheoccupantwillimpactthatsurface.Irregularsurfacescreatedbysomearmrestsorinteriortrimsasobservedforexample,intheE350,canexacerbatetherelativedisplacementofbodysegmentsandcan increasetheriskof injury. IntheE350theheadandshoulderareprojected intothetriangularshapedvoidthat is formedbythewindowand interiortrimandshown inFigure19.Thismeansthattheheadandupperthoraxcanpivotaboutthetrim.Thehead strikes thewindowwith increased speed and the ribs are in direct contactwith theintrudingtrim.IntheMFAB,thekinematicsaredifferentbecausetheflatwallsurfacepreventsthestrucksidedummyfrompivoting.Sincethesideofthedummyisalreadyincontactwiththesidewallpriortothecrash,thereisverylittlespaceforthedummytoaccelerate.TheWorldSIDtranslateslaterallycompressingtheshoulder,whilethehipsarerapidlyblockedbythesidewallandtheheadstrikesthewindowframe.Thebonyprotuberanceoftheshoulderrepresentedinthiscasebythehardwareinthedummyshoulderandpelvisreducetheextentofdirectcontactwiththeribs.Table3.DistancesfromWS50thdummylandmarkstothesidewallasafunctionofvehicleLandmarks E350(mm)MFAB(mm)headshoulderpelvis25017075140045It is important tonote that thekinematicsandassociated injury risksdescribedhereinapplyonlytothespecificcrashconfigurationthatwastested,thesize(includingshape)ofthestrucksideoccupantsandtheirplacementrelativetothesidestructure.Furthermore,sincetheMFABand E350 were stationary when impacted, themotion of the occupants did not take intoaccount theeffectsofprecrashmotion, typicallyassociatedwithavoidancemanoeuvresandbraking.Theheadofashorterstaturedoccupantforexample,couldhavestruckthewindowoftheMFABinsteadofthestiffframe,resultinginashatteredwindowandejectionofthehead.Ashorter occupant in the E350may not have extended as far out of thewindow. Similarly,outcomeswould have been different had the occupantsnot been seated upright. Since thewindowframeandpillarsoftheMFABarenotprotectedwithenergyabsorbingmaterialthereisariskofheadinjuryshouldimpactoccur.Thefurthertheheadtravelspriortotheimpactthegreaterthevelocityofimpactandthegravertheriskoftraumaticheadinjury.PAIREDCRASHTESTINGofa15PASSENGERVAN&MFAB 25 Aknowncountermeasuretooptimizeoccupantprotectionandreducetheriskofheadinjuries,isthesidecurtainairbag.InthecaseoftheE350,acurtainthatcoulddeployfromtheroofrailjustabove thewindowandextenddown to the trimmighteliminate the triangulargapandcreateacushionedwall.While it isnotknownhow thismightperform insuchaseveresideimpactsuchasystemcangenerallymitigateagainstejection,reduce impact to theheadandprotect occupants from shattered glass. Similarly for theMFAB, while it is not known howeffectiveasidecurtainairbagmaybeinsuchasevereimpactcollision,aninflatablecurtaincangenerallymitigateagainstejectionandreducetheseverityofpotentialheadimpactswiththewindow frame. The addition of energy absorbing material to exposed interior structuralelementsoftheMFABmayalsoreducetheseverityofheadstrikesinlessseverecollisionsandenhancetheprotectionprovidedbyaninflatablecurtainThekinematicsandinjurymechanismsobservedinboththeE350andtheMFABareconsistentwith the dummy motions and responses that are observed in other passenger vehiclessubjectedtosideimpactcrashtesting.Sideimpactregulationsandconsumersafetyratingtestprogramsemploytestspeedsthataresubstantiallylessseverethanthe75km/hbulletvelocityinthispairedtesting.Forexample,theAmericanNewCarAssessmentProgram(NCAP)andtheFMVSS 214 regulation accelerate a crabbed deformable barrier at 62km/h and 54 km/h,respectively into the side of passenger vehicles. The Insurance Institute forHighway Safety(IIHS)usesamovingdeformablebarrierthatisintendedtosimulatethefrontendofapickuptruck.Thisbarrierhasagreatersurfaceareaandhas100mmmoregroundclearancethantheU.S. compliance barrier. The IIHS test which has been instrumental in motivating theautomotive industry to introduce head curtain technology and other side impactcountermeasuresemploysa test speedof50km/h.Vehiclemanufacturershave spentmanyyears examining the effects of side structures and interior trim architecture in an effort tomitigatetraumacausedbysideimpactcollisions.Theintroductionofaircurtaintechnologyhasproventobepossibly,themosteffectivecountermeasuretoreducehead injuries insideandrollovercollisions.EffectofseatspacingonloadingexposureTheheadofthe foremostdummyoccupant intheMFABwas locatedapproximately400mmfurtherforwardofthecloseststriking longitudinalthantheheadofthedummyseated intheE350.Thismeansthatforthisspecificcrashconfiguration,anoccupantseatedinthefirstrowwouldhavebeenfurtherfromtheimpactregionintheMFABthanintheE350andexposuretocollisionforceswouldhavebeensomewhatlesssevere.Thedifferenceinspacingofthecenterandrearseatsbetweenthetwovehicleswasnotasgreatasforthefrontrowseat.PAIREDCRASHTESTINGofa15PASSENGERVAN&MFAB 26 NonStrucksideOccupantsAlldummiesseatedonthenonstrucksideofboththeE350andtheMFABhadhead impactsthatwereconsistentwithmoderate to severehead injuries. Inbothvehicles the threepointbeltswere ineffective inrestrainingtheuppertorso. IneachofthethreerowstheforcefromtheimpactcausedthesmallfemaleWorldSID5thandthelargerES2rerepresentativeofamidsizedmaletopivotaboutthelapportionofthethreepointbelt.IntheE350thenonstrucksidedummieswereprojectedacrossthebenchseat.Theheadsofallthree dummies collided with the dummy seated on the struck side of the bench. In therearmostrowtheWS5thcollidedwiththeSIDsseatedadjacenttotheWS50th.Thelapportionoftheseatbeltspenetratedeachofthedummyabdomens.InthecaseoftheWS5thseatedintherearmostrowthebeltloadscombinedwiththemotionofthedummyweresevereenoughtotearthelowerspine.SincethisdummyhadbeensubjectedtosimilarloadsintheMFABtestitmaybethatsomepreexistingdamagecontributedtotheseveringofthelowerspine.IntheMFABthenonstrucksidedummieswereprojectedacrossthecentreaisle.Theheadsofthe two small femaleWS5thdummies struck the seat thatwas located in the same rowbutacross the aisle. The spacing between the small female and struck side dummieswas largeenoughintheMFABtopreventdummytodummycontact.TheheadoftheES2recollidedwiththeWS50thdummyseatedonthestrucksideoftherow.AsintheE350theshoulderportionofthethreepointseatbeltfailedtorestraintheuppertorsoandeachdummypivotedaboutthelapbelttowardstheaisle.ThepelvisoftheWS5thseatedinboardinthefrontrowslidintotheaisleas thedummyabdomenandpelviswere restrainedby theseatbelt.TheWS5thseatedoutboardintherearmostrowslidacrosstheinboardseatandwaspitchedheadfirstintotheaisle.Inallcasespenetrationoftheseatbeltintotheabdominalregionwasobserved.Since the dummies are not designed tomeasure responses from such severe out of planemotion it isnotpossible toquantify the riskof injuryon thebasisofdummy response. Forinstance,thereistodate,noinstrumentcapableofmeasuringorindeeddetectingtheextentofbeltintrusionintotheabdominalcavity.Basedonvisualanalysisofthevideostherewouldbeastrong likelihoodofsevereabdominal injury including liver,spleenandbowelcontusionsandlacerations.LowerribfracturesandseriousspinaltraumacouldnotberuledoutforanyofthenonstrucksideoccupantsineithertheE350ortheMFAB.Theprotectionofnonstrucksideoccupantsisachallengeinallpassengervehiclesinvolvedinsideimpactcrashes.Theproblemisbynomeansuniquetoeither15passengervansorbuses.Untilvery recentlyattentionhas focussedalmostexclusivelyon theprotectionofstrucksideoccupants.InfactcurrentworldregulationsandconsumerprogramssuchasNCAPandIIHSforside impact protection include only struck side occupants. As a result, there has beenPAIREDCRASHTESTINGofa15PASSENGERVAN&MFAB 27 comparatively littleemphasisdirectedtowardsthedevelopmentofcountermeasures.Certainmanufacturersare introducingorexploringthefeasibilityofsideairbagsthatwoulddeploy inthecentreofthevehicle,betweentwooccupants,whileothersareinvestigatingtheroleofbeltpretensioners and seat designs. Clearly, in severe side impact crashes the challenges ofoccupant protection are so great that theywill likely require a comprehensivemultisystemapproach that combines structural, seat and restraint designs as well as supplementaryrestraintsystems,quitepossiblyintheformofsideairbagtechnology.CONCLUSIONApairedcrashtestprogramwasconducted,tocomparetheprotectionavailabletorestrainedoccupants of a 15passenger van to that available to restrained occupants in anMFAB in aseveresideimpactcrashtest.Amodelyear2011,Girardinmultifunctionalactivitybus(MFAB)andamodelyear2011FordE35015passengervanwereeach impactedat90degrees intheleftrearaxlebyamodelyear2009FordF150travellingat75km/h.Two of the three crash test dummies seated on the struck side of the E350were partiallyejected through the shattered window. Based on the injury responses obtained from theWorldSID 50th dummies seated at these locations it is anticipated that a human occupantexposedtothesameconditionsasthistestconfigurationwouldhavehadariskofmoderatetoseverehead injuryandmoderatetoseriouschestandabdominaltrauma.ThearmoftherearmostWorldSID50thpositionedonthestrucksideoftheMFABwasejected.ThemotionoftheheadwasstoppedbythewindowframeforallthreedummiesseatedonthestrucksideoftheMFAB. Therewasariskofmoderatehead injuryfortherearmoststrucksideoccupant.Thesmallfemaledummyseated inthefrontrowoftheE350hadresponsesthatwereconsistentwithariskofsevereabdominal injury,whichwasexacerbatedbyan impactfromthefarsidedummy seated in the same row; and a riskofmoderate chest andpelvic injuries causedbycontactwiththeinteriortrim.ThesameoccupantintheMFABdemonstratedariskofseriousinjurytotheabdomenfromcontactwiththesidewallofthebus.The injurymeasuresfortheoccupantsoftheMFABwerelessseverethanfortheE350becauseoftheircloseproximitytothe flatwall surface of the interior sidewall.A difference in initial occupant position in theMFABwherebytheoccupantwouldbeseatedfurtherinboard,slouchedontheseatorleaninginboardwouldlikelyincreasetheriskofinjury.The lapand shoulderbelts inboth theE350and theMFABwere ineffectiveat restraining theupper torso of all the nonstruck side occupants. The closer proximity of the small femaleoccupantsseatedinthesamerowcontributedtomoresevererisksofheadandneckinjuriesintheE350.TheES2reandWorldSIDdummiesseated inthesecondrowdidcollide.ForthemidsizemaledummiesseatedonthenonstrucksideofboththeMFABandtheE350therewasariskofsevereheadinjury,seriouschestandabdominaltrauma.Alldummiesseatedonthenonstrucksideofbothvehiclesexhibitedkinematicsthatsuggestahighriskofseriousbeltrelatedinjuries.Theoutcomeof thispairedcrash testing iscomparable toother side impactcrash tests thathavebeenpreviouslyconductedwithpassengervehicles.Aknowncountermeasuretoreducethe risk of head injury for struck side occupants is inflatable curtain technology. ThePAIREDCRASHTESTINGofa15PASSENGERVAN&MFAB 28 countermeasuresto limitoccupantejection fromthe seatbeltsandsubsequentoccupanttooccupant contact in all types of passenger vehicles are still under development. Potentialcandidatemeasuresincludeimproveddesignsofrestraintsandseatsandtheintroductionofinboardsideairbags.The testing conductedbyTransportCanada represents very specific combinationsof vehiclemodels,speedattimeofimpact,dummiesused,seatingconfiguration,etc.Theresultsdonotlend themselves to generalization on how the same vehicle models would behave underdifferent testing conditions or how different vehicles (othermodels of 15 passenger vans,MFABs)wouldbehaveunder thesame (ordifferent) testingconditions.Therefore,TransportCanadadoesnotdrawanygeneralconclusionsconcerningthecrashworthinessof15passengervansnortheMFABtypesofvehicles.The resultsof thepairedcrash testingprojectdonotsupport theneed for further testingatevenmoresevereconditions(eg.heavierbulletvehicle,higherspeedof impact,bothvehiclesinmotion,obliqueangleofimpact),wherethecasualtieswouldbeexpectedtobeexacerbated.Hence,noadditionalcrashtestingwillbeconducted. PAIREDCRASHTESTINGofa15PASSENGERVAN&MFAB 29 FUTUREWORKAspartof itsregulatoryprogram,TransportCanadawillcontinuetoassesstheapplicabilityofcountermeasuresfortheprotectionofoccupantsof lightdutyvehicles ingeneral,duringsideimpact collisions. This will be undertaken in the context of the CanadaU.S. RegulatoryCooperationCouncilandtheactivitiesthereunder.REFERENCESKuppa,S.,(2004)InjuryCriteriaforSideImpactDummiesNationalTransportationBiomechanicsResearchCenterNationalHighwayTrafficSafetyAdministrationPetitjean,A.,Troseille,X.,Petit,P.,Irwin,A.,Hassan,J.,Praxl,N.(2009)InjuryRiskCurvesfortheWorldSID50thMaleDummy.StappCarCrashJournal,Volume53,November2009,SocietyofAutomotiveEngineers,Warrendale,PA.Tylko,S.,Charlebois,D.,OptimizingtheProtectionofSchoolBusOccupantsTransportCanadaDraftInternalReportASFB201003,May2010.TABLE OF CONTENTSTABLE OF FIGURESEXECUTIVE SUMMARYINTRODUCTIONTEST MEHODOLOGYTest Vehicles:Striking (Bullet) Vehicles:Crash Configuration:Crash Test Dummies and Placement In Test Vehicles:CAMERAS and PLACEMENT:InstrumentationRESULTSVehicle KinematicsVehicle IntrusionOccupant KinematicsFront row kinematics: ////Second row kinematics: Third row kinematics: Injury MeasuresStruck side OccupantsFar-side (non-struck) OccupantsDISCUSSIONStruck side OccupantsEffect of the interior trim on loading exposure and injury riskEffect of seat spacing on loading exposureNon-Struck side OccupantsCONCLUSIONFUTURE WORKREFERENCES

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