Side Impact Vehicle Testing: Development of A Lateral ?· Side Impact Vehicle Testing: Development of…

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Side Impact Vehicle Testing: Development of A Lateral Test Procedure for Child RestraintsTaryn Rockwell, ACE Systems Technologies, Inc.2BackgroundTREAD Act Nov. 2000Mandated that NHTSA determine whether to:l Apply scaled injury criteria performance levels developed for FMVSS No. 208, to CRS covered in FMVSS No. 213l Include CRS in NCAP crash testsIn response, NHTSA:l Issued NPRM to address proposed changes to 213 (Docket No. 2002-11707-3) proposed 208 scaled injury performance levelsl Issued ANPRM for child protection in side & rear impactl Conducted frontal & side NCAP vehicle tests with CRABI 12MO & Hybrid III 3YO in CRS3Ongoing Research to Address Issues Raised in the ANPRMEvaluating real world side impact datal CHOP, NASS, FARS, SCIEvaluating different lateral test procedures for evaluating CRSsl ISO, Japan NCAP, Australia, Euro NCAPSled testingl Countermeasuresl Dummiesl Q3 vs. Hybrid IIIl IARVsVehicle testingl NCAP and R&D4Objectives of This ResearchAddress some of the issues raised in the ANPRM including:l Determining child injury mechanisms in side impact vehicle testsl Compare performance in vehicle tests to that of suggested 90o sled tests5Vehicle Selection8 vehicles selected:l 5 from list of vehicles to be selected for 2002 SINCAPl 3 vehicles piggy-backed to R&D tests with ES-2 dummyThe following considered when selecting vehicles:l Difficulty of correctly positioning rear SID dummy exempt from side NCAP testingl Popular modelsl Covered various vehicle classes (2-dr. pass. cars, 4-dr. pass. cars, SUVs, vans, pickups)l Vehicle availability* Did NOT attempt to get cross-sample from vehicle manufacturers6Vehicle ConfigurationFor any one particular vehicle, the following were identical for both outboard rear seating positions:l Model of CRSl CRS orientationl CRS belt configurationl Child dummy7Model of CRSSafety 1st Forerunnerl 5-point harnessl Convertiblel 5-35 lbs. rear-facingl 22-40 lbs. forward-facingl Equipped with lower anchorages & tether (LATCH)Evenflo On-My-Wayl 5-point harnessl Rear-facing only (Infant seat)l 5-20 lbs.l Equipped only with tether not used8CRS Belt Configuration & OrientationSafety 1st Forerunnerl VSB, no tether, RFl VSB, tether, FFl LATCH, FFl Lower anchorages, no tether, RFEvenflo On-My-Wayl VSB, no tether, RF9Child Dummy Selection & InstrumentationHybrid III 3YO dummy12MO CRABI dummyEquipped with:l Upper & lower neck load cellsl Tri-axial head, chest, and pelvis accelerometersl Chest lateral spring potentiometer for 3YO only10Side NCAP Test ProcedureMDBl 27o crabbed anglel 62.0 km/h (38.5 mph)Target vehiclel Positioned at 63o to the line of forward motionl Stationaryl Impacted on drivers sideSimulates car moving at 55 km/h hitting another car moving at 27 km/h11Video of Crash Test Vehicle B (Pickup)12Post-Test CRS ExaminationPost-test examinations showed:l No CRS damagedl No plastic (permanent) deformation of lower anchorages in vehicle or connection hooks on CRS l All vehicle seat belts intact and without damage13Injury CriteriaSuggested in ANPRM issued to address side impact protection for child occupants Docket No. 02-12151Examination of IARVs for side impact dummies only used as a baseline comparison3017Extension6843Flexion21201460Compression23401460Nij Intercepts: Tension3434Chest Deflection55503 ms Chest Clip570390HIC 153YO Hybrid III12MO CRABIINJURY CRITERION14Head Injury Criterion12MORFNLPickup3YOFFL4-dr car3YO3YO12MO12MO12MO12MOSUV2-dr car4-dr car4-dr carVanPickupFFFFFFRFRFRFNLLLLLNL0 .00 .20 .40 .60 .81 .01 .21 .41 .61 .82 .0Normalized HIC 15A B C D E F G HV e h i c l e sHead In ju ry Cr i t e r ion 15 mi l l i seconds (H IC 15 )N e a r - S i d eFa r -S ide*4 .42 - Va lue o f f cha r t15Head Injury Criterion Vehicle E (4-dr. car)16Intrusion Vehicle E (4-dr. car)17Intrusion at Window SillVehicle Intrusion at Window Sill-200-1000100200300400-1500 -1000 -500 0 500 1000 1500 2000 2500 3000 3500Distance From Impact (mm)Intrusion (mm)ABCDEFGH18Thoracic Criteria Chest Acceleration0 .00 .51 .01 .52 .02 .5Normalized Chest Acceleration (G's)A B C D E F HV e h i c l e sC h e s t A c c e l e r a t i o nN e a r - S i d eFa r -S ide12MORFNLPickup3YOFFL4-dr car3YO12MO12MO12MO12MOSUV4-dr car4-dr carVanPickupFFFFRFRFRFNLLLLNL19Intrusion Vehicle F (4-dr. car)Dummys chest at approx. window sill level20Intrusion at Window SillVehicle Intrusion at Window Sill-200-1000100200300400-1500 -1000 -500 0 500 1000 1500 2000 2500 3000 3500Distance From Impact (mm)Intrusion (mm)ABCDEFGH21Dummy PositioningCBGAHDEFVanPickup2-dr. carPickupSUV4-dr. car4-dr. car4-dr. carChild Dummy Closer to DoorRankings 1-81 = closest to door8 = farthest away from door20215712322720Total46123874Ranking2221E1112F6645G4457H3333D8888C7776B5564AHDADCDHSVehicle22Thoracic Criteria Chest Deflection3YO dummy onlyl 3 vehicles F, G, & HDummy readings normalized to 34 mm All recorded injuries well below IARVl Negligible for far-side dummyHighest recorded value: 0.58 near-side dummy in vehicle F23Neck Criteria - Nij Faxial = Fz Fcritical = Max. force in z-direction (tens./comp.) Moc = My + (correction factor)Fx Mcritical = Max. moment about y-axis (flex./ext.)Nij = max[Faxial/Fcritical + Moc/Mcritical]* Development of Improved Injury Criteria for the Assessment of Child Restraint Systems. Docket No. 2002-11707-18-3068-212023403YO-1743-1460146012MOExtension (N-m)Flexion (N-m)Compression (N)Tension (N)DummyIN-POSITION LIMITS - Nij INTERCEPTS24Neck Criteria - Nij0 .00 .20 .40 .60 .81 .01 .21 .41 .61 .8Maximum NijA B C D E F G HV e h i c l e sM a x i m u m N i jN e a r - S i d eFa r -S ide12MORFNLPickup3YOFFL4-dr car3YO3YO12MO12MO12MO12MOSUV2-dr car4-dr car4-dr carVanPickupFFFFFFRFRFRFNLLLLLNL25Nij Failure Modes for 12MO CRABIMaximum Nij Moment and Force Levels for Near Side and Far Side 12-Month-Old CRABI Dummies in Side NCAP CRS Tests-2500-2000-1500-1000-50005001000150020002500-40 -30 -20 -10 0 10 20 30 40 50 60Moment (N-m)Force (N)Near Side DummyFar Side DummyTension-FlexionCompression-FlexionCompression-ExtensionTension-ExtensionDiamond formed by Nij interceptsMy & Fz injury values at time of max. Nij foundExceed 1 of 4 modes of neck motion if recorded moment/force combination falls outside diamondEDCBA12MORFNLPickup12MO12MO12MO12MO4-dr car4-dr carVanPickupFFRFRFRFLLLNL26Nij Failure Modes for 12MO CRABI Tension/ Extension in vehicle C (van)Neck tension head up relative to neck or chest down relative to neckNeck extension chin up, away from sternum, forcing head back27Nij Neck Motion for 3YO Hybrid IIIMaximum Nij Moment and Force Levels for Near Side and Far Side 3-Year-Old Hybrid III Dummies in Side NCAP CRS Tests-2500-2000-1500-1000-50005001000150020002500-40 -20 0 20 40 60 80Moment (N-m)Force (N)Near Side DummyFar Side DummyTension-FlexionCompression-FlexionCompression-ExtensionTension-ExtensionVehicle FHGF3YOFFL4-dr car3YO3YOSUV2-dr carFFFFNLL28Nij Neck Motion for 3YO Hybrid IIITension/Extension in vehicle G (2-dr. car)Tension/ Flexion in vehicle F (4-dr. car)Neck tension head up relative to neck or chest down relative to neckNeck flexion chin down toward sternum & head curls forward 29Resultant Pelvis Acceleration0204060801 0 01 2 01 4 01 6 0Resultant Pelvis Acceleration (G's)A B C D E F G HV e h i c l e sResu l tan t Pe lv is Acce le ra t ionN e a r - S i d eFa r -S ide12MORFL4-dr car12MORFLVan12MORFNLPickup3YOFFL4-dr car3YO3YO12MO12MOSUV2-dr car4-dr carPickupFFFFFFRFNLLLNL30Summary of InjurySeveral vehicles exceeded numerous injury criteria 3YO3YO3YO12MO12MO12MO12MO12MODummy Type0.470.840.14Near-SideSUVH0.350.470.05Far-Side0.84N/A0.55Near-Side2-dr. carG0.70N/A0.66Far-Side0.601.520.53Near-Side4-dr. carF0.470.410.10Far-Side1.601.881.74Near-Side4-dr. carE0.850.710.56Far-Side0.972.074.42Near-Side4-dr. carD1.330.731.04Far-Side1.63N/A0.45Near-SideVanC0.600.330.14Far-Side1.290.770.28Near-SidePickupA0.550.470.09Far-SidePickupVehicle TypeFar-SideNear-SideDummy Position1.000.460.110.76N/A0.18BNijChest GsHIC 1531Comparison of Sled Tests to Vehicle Tests32Suggested Lateral Sled Tests to Be Added to 213ANPRM suggested 2 Options:l 90o, no rigid walll 20 mphl sine pulse or upgraded 213 pulsel Tethered CRSl Impose 20 head excursion limit l 90o, rigid-walll 15 mph l Grand Am pulse derived from pulse of Pontiac Grand Am when tested both under 214 (15 mph w/ 21g peakaccel.) & side NCAP (21 mph w/ 26 g peak accel.)l No head excursion limit necessary33Comparison of 90o (No wall) TRC Sled Tests to SINCAP Vehicle Tests Near-side dummy readings for HIC 15 & chest G in sled tests (no wall) much lower than in vehicle testsHead & Chest Injury for Near-Side Dummies - Side NCAP Tests Vs. TRC 90o Sled Tests (No Wall)0.00.51.01.52.02.53.03.54.04.55.00.0 0.5 1.0 1.5 2.0 2.5Normalized Chest GNormalized HIC 15TRC 1/2 Sine Pulse (3YO)TRC 213 Pulse (3YO)SINCAP (3YO)SINCAP (12MO)34Comparison of 90o (No wall) TRC Sled Tests to SINCAP Vehicle TestsInconclusive whether HIC 15 & chest G readings for far-side dummy in vehicle tests greater than in sled tests (no wall)Head & Chest Injury for Far-Side Dummies - Side NCAP Tests Vs. TRC 90o Sled Tests (No wall)0.00.20.40.60.81.01.20.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0Normalized Chest GNormalized HIC 15TRC 1/2 Sine Pulse (12MO)TRC 213 Pulse (12MO)SINCAP (3YO)SINCAP (12MO)35Comparison of TRC 90o Rigid Wall Sled Tests to SINCAP Vehicle Tests90o Y-acceleration on rear floorpan for five vehicles-10-505101520253035-0.02 -0.01 -0.00 0.01 0.02 0.03 0.04 0.05 0.06 0.07 0.08 0.09 0.10Right Rear Floorpan 90 degrees (Y)G'STime in SecondsRSX Impreza Wagon Santa Fe Sentra TundraG (2-dr. car) F (4-dr. car) H (SUV) E (4-dr. car) A (Pickup)36Average acceleration curve in y-direction for 5 vehicles (v = 17.38 mph) vs. pulse for 15 mph rigid wall sled testComparison of TRC 90o Rigid Wall Sled Tests to SINCAP Vehicle Tests-5051015202530-0.02 -0.01 -0.00 0.01 0.02 0.03 0.04 0.05 0.06 0.07 0.08 0.09 0.10G'STime in SecondsVRTC 15 mph Rigid Wall Sled Test Pulse Avg. Accel. from Rear Floorpan of SINCAP Tests~ 0.01 sec.~ 8 GsNote different shape37Comparison of TRC 90o Rigid Wall Sled Tests to SINCAP Vehicle TestsIn general, near-side dummy readings for HIC 15 & chest G in 15 mph rigid wall sled tests are similar to readings in SINCAP vehicle testsHead & Chest Injury for Near-Side Dummies - Side NCAP Tests Vs. TRC 90o Rigid Wall Sled Tests at Various Speeds0.01.02.03.04.05.06.07.00.0 0.5 1.0 1.5 2.0 2.5Normalized Chest GNormalized HIC 15TRC (10 mph)TRC (15 mph)TRC (20 mph)SINCAP (17.4 mph)38Preliminary ObservationsBased on limited test series:l CRSs withstand severity of side impact crash conditionsl Near-side dummy readings generally greater than far-side dummy readingsl Contributors: Intrusion & lower anchorage locations changes relative position of dummy39Preliminary ObservationsSled tests vs. vehicle tests:l Sled test (no wall)l Near-side dummy - readings for HIC 15 & chest G much lower than in vehicle testsl Far-side dummy inconclusive l Sled test (rigid wall)l Near-side dummy readings for HIC 15 & chest G for test at 15 mph similar to dummy readings for vehicle tests 40Next StepsEvaluation of countermeasuresEvaluation of biofidelity of dummies for side impactAdditional vehicle testingPossible development of lateral impact test procedure for CRS