Pedestrian Protection in US Vehicles: An Evaluation Using the TRL & Flex GT Legforms

Transcription

1 Pedestrian Protection in US Vehicles: An Evaluation Using the TRL & Flex GT Legforms Ann Mallory Transportation Research Center Inc. Jason Stammen NHTSA Vehicle Research and Test Center Government/Industry Meeting May 2008

2 Overview TRL Legform - tested 9 US vehicles FLEX/GT Legform - tested 2 US vehicles Global Technical Regulation Lower Legform Test Procedures Experience with legforms and test procedures Evaluate US vehicle performance

3 GTR Lower Legform Procedure 40 km/h Within GTR test zone on vehicles TRL Lower Legform Static and dynamic certification every 20 impacts 25 mm (1 ) above ground reference level Flex-GT Legform Dynamic certification after every test 75 mm (3 ) above ground reference level

4 TRL Flex GT Knee Injury Measures Knee Shear/Bending Ligament Elongation Fx Measures Tibia Acceleration Bending Moment

5 TRL Legform Testing

6 Vehicles Tested TRL Legform Testing 2 Passenger Cars (PC) 3 Sport Utility Vehicles (SUV) 2 Pickup trucks (PU) 1 Minivan (MV) 1 Full-size van (VAN) 2006 VW Passat 2002 Mazda Miata 2006 Dodge Durango 2002 Jeep Wrangler 2005 Honda CR-V 2005 Chevy Silverado 2006 Toyota Tacoma 2006 Toyota Sienna 2003 Ford E350 Van

7 Test Locations TRL Legform Testing Up to 5 impacts Evenly spaced from centerline to zone edge Tested on both sides for multiple tests per bumper Test Zone

8 RESULTS TRL Legform Testing

9 35 Bending Angle (degrees) GTR Limit 19 TRL Legform Testing Out of alignment limits Out of speed range Bumper height - >50 cm ` Passat Miata Durango Wrangler CR-V Silverado Tacoma Sienna E-350 Pass. Cars SUVs Pickups Minivan Van

10 Shear Displacement (mm) GTR Limit 6 mm TRL Legform Testing Out of alignment limits Out of speed range Bumper height - >50 cm Passat Miata Durango Wrangler CR-V Silverado Tacoma Sienna E-350 Pass. Cars SUVs Pickups Minivan Van

11 Tibia Acceleration (g) GTR Limits 170g and 250g TRL Legform Testing Out of alignment limits Out of speed range Bumper height - >50 cm Passat Miata Durango Wrangler CR-V Silverado Tacoma Sienna E-350 Pass. Cars SUVs Pickups Minivan Van

12 2005 Honda CR-V Passed 4/5 A B C D B A E C (Pass) TRL Legform Testing C D B A E Pass / Fail Peak bending angle (degrees) Peak shear displacement (mm) E (Fail) Peak tibia acceleration (g) / 250

13 2002 Mazda Miata Passed 1/5 TRL Legform Testing C D B A E C D B A E Pass / Fail Bending angle (degrees) Shear displacement (mm) Tibia acceleration (g) / 250 C (Pass)

14 2002 Jeep Wrangler Passed 1/5 TRL Legform Testing C D B A E C D B A E Pass/ Fail Bending angle (degrees) Shear displacement (mm) E (Pass) Tibia acceleration (g) / 250

15 Comments on TRL Tests TRL Legform Testing No vehicle passed all impacts CR-V came closest with excellent performance in 4 of 5 tests All other vehicles tested performed poorly relative to GTR limits Energy-absorption and support above/below knee appear to be key for good performance. Worst performers had little deformation and applied forces over small area.

16 FLEX GT Legform Testing

17 Vehicles Tested FLEX GT Legform Testing Selected from impact locations that passed GTR requirements Honda CR-V (A & C): - Worst and Best of the passed impacts Mazda Miata (C): - Center impact location A C C

18 RESULTS FLEX GT Legform Testing

19 Fracture Measures Proposed limit Nm FLEX GT Femur 3 Femur 2 Femur 1 Tibia 1 Tibia 2 Tibia 3 Tibia 4 FLEX GT Legform Testing Miata Center CR-V Outboard CR-V Center Bending Moment (N-m) TRL Upper tibia acceleration (g) TRL Upper Tibia Acceleration (g)

20 Knee Bend Measures Proposed limit mm FLEX GT Legform Testing FLEX GT MCL Miata Center CR-V Outboard CR-V Center Flex Ligament Elongation (mm) Bending Angle (Degrees) TRL Bending Angle (degrees)

21 Shear Measures FLEX GT Legform Testing FLEX GT PCL ACL Miata Center CR-V Outboard CR-V Center Elongation (mm) TRL Shear displacement (mm) TRL Knee Shear

22 FLEX GT Legform Testing Comments on Flex GT Tests Flex GT only used at friendliest impact locations Flex GT indicated higher severity relative to proposed limits Flex GT ranked severity of the three impact locations similarly to TRL

23 Summary Lower leg test performance generally poor relative to GTR requirements Small number of individual test points passed, some with wide margin No vehicle passed across test zone Energy-absorption and distributed support are most effective solutions When tested on friendliest impact locations, Flex GT indicated higher severity than TRL, but ranked impact locations similarly to TRL

24 Pedestrian Protection in US Vehicles: An Evaluation Using the TRL & Flex GT Legforms Ann Mallory Transportation Research Center Inc. Jason Stammen NHTSA Vehicle Research and Test Center Government/Industry Meeting May 2008

25 TRL Legform Testing Lower Bumper Reference Line (LBRL) Height Across Bumper Test Area LBRL < 425 mm Lower leg test required 425 LBRL< 500 mm Manufacturer s choice LBRL 500 mm Upper leg test required LBRL Height (mm) 2006 Dodge Durango SUVs 2002 Jeep Wrangler 2005 Honda CRV 2005 Chevy Silverado PU 2006 Toyota Tacoma MV 2006 Toyota Sienna Van 2003 Ford E350 Van 2006 VW Passat PC 2002 Mazda Miata Minimum Height Max. Height

26 TRL Flex GT Honda CR-V Mazda Miata