2001 SAE Government Industry Meeting

Vehicle Compatibility Research Program

National Highway Traffic Safety Administration U.S. Sales and Registrations of Light Trucks and Vans

60.0

50.0

40.0

30.0

Percentage (%) 20.0

10.0

0.0 1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 Year LTV Sales LTV Registrations Fatalities in Vehicle-to-Vehicle Collisions

7,000

6,000

5,000

4,000

Fatalities 3,000

Car-Car Collisions 2,000 LTV-Car Collisions LTV-LTV Collisions

1,000

0 1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 Aggressivity Metric

Fatalities inCollision Partner Aggressivity = Numberof Crashesof SubjectVehicle

Using 1995-1999 FARS for fatality counts 1995-1999 NASS GES number of crashes

2 vehicle crashes, both vehicles < 10,000 lbs GVW Both vehicles must be model year 1990 or newer Count only driver fatalities between 25 and 55 years old Aggressivity Metric – All Crashes

Large Van 3.12 Large Pickup 2.89 Large SUV 2.01 Small SUV 1.51 Compact Pickup 1.34 Minivan 0.95 Large Car 0.83 Midsize Car 0.75 Subject Vehicle Compact Car 0.59 Minicar 0.46 Subcompact Car 0.41

0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 Deaths in other Vehicle / 1000 Police Reported Vehicle- Vehicle Crashes with Subject Vehicle Frontal-Frontal crashes

Large Pickup 69.27 Large Van 55.51 Large SUV 30.62 Small SUV 20.58 Compact Pickup 18.54 Minivan 17.77 Large Car 14.09

Subject Vehicle Compact Car 11.89 Midsize Car 11.28 Subcompact Car 5.99 Minicar 5.45

0 20 40 60 80 Deaths in other Vehicle / 1000 Police Reported Frontal-Frontal Crashes with Subject Vehicle Frontal-Side crashes Large Pickup 4.02 Large Van 3.88 Large SUV 3.52 Small SUV 2.40 Compact Pickup 1.82 Minivan 1.33 Large Car 1.22

Striking Vehicle Midsize Car 0.76 Compact Car 0.59 Subcompact Car 0.48 Minicar 0.33

0 1 2 3 4 5 Deaths in Struck Vehicle / 1000 Police Reported Side Impact Crashes with Striking Vehicle Vulnerability Metric, Frontal-Side crashes

Large Pickup 0.02 Large SUV 0.19 Large Van 0.33 Minivan 0.53 Compact Pickup 0.76 Small SUV 0.98 Large Car 1.01

Struck Vehicle Midsize Car 1.53 Compact Car 1.68 Subcompact Car 1.92 Minicar 6.79

0 2 4 6 8 Deaths in Struck Vehicle / 1000 Police Reported Side Impact Crashes with Any Vehicle Development of Test Methods to Evaluate Compatibility • Goals: – Evaluate occupant protection in a crash with average or most likely crash partner • Self protection – Evaluate other vehicle crash severity with average or most likely crash partner • Partner protection Loadcell MDB Testing

• LCMDB can be designed to represent the crash partner vehicle – Height, width, stiffness, depth of crush to be determined based on fleet survey data – Delta V of test vehicle will depend upon its weight • Loadcells intended to measure distribution of force during crash – Aggressivity estimates may be derived from data • Baseline research was presented as 2001 SAE Congress, 2001-01-1167 Research Goals

• Use Frontal-Frontal to evaluate feasibility – Collinear, 35 mph each vehicle – Full frontal engagement – 1996 Plymouth Neon, 1997 Dodge Caravan – Baseline 214 MDB face • Compare LCMDB-to-vehicle and vehicle-to- vehicle responses – MDB weight was adjusted to simulate collision partner Summary of previous Test Results • Bumper element on LCMDB face diffused the measured force distribution – Distribution of force was not measured • Insufficient energy absorption, 214 face bottomed out early in the test – LCMDB crashes were more ‘severe’ than vehicle-to- vehicle crashes • Significant energy transfer occurred outside the loadcell face Extended Test Matrix

Test Vehicle 1 Vehicle 2

3362 LCMDB 1996 Plymouth Neon 56.2 kmph, 2051 kg 55.9 kmph, 1382 kg 3413 LCMDB 1997 Dodge Caravan 56.2 kmph, 1377 kg 56.8 kmph, 2138 kg 3414 1997 Dodge Caravan 1996 Plymouth Neon 56.5 kmph, 2060 kg 55.9 kmph, 1378 kg

3608 LCMDB Bumper Removed 1996 Plymouth Neon 58.0 kmph, 2050 kg 57.1 kmph, 1382 kg 3609 LCMDB Bumper Removed 1997 Dodge Caravan 56.2 kmph, 1377 kg 56.8 kmph, 2139 kg Modified LCMDB Occupant Injury

• Belted 50th male driver • Belted 5th female passenger • LCMDB tests without bumper produced higher HIC15 measurements – All injuries higher than baseline test – Other injuries were comparable between baseline and modified LCMDB Caravan Driver Injury

2.5

2

1.5

1

Normalized Injury 0.5

0 HIC15 Nij Chest G Chest L Femur R Femur Disp

Baseline LCMDB Mod LCMDB Neon Driver Injury

2.5

2

1.5

1

Normalized Injury 0.5

0 Hic15 Nij Chest G Chest L Femur R Femur Disp

Baseline LCMDB Mod LCMDB Loadcell Measurements

• Neon Loadcell measurements improved without the MDB bumper – Reduced bending of the honeycomb face for the Neon test • Caravan measurements matched overall force, but changed distribution • Existing MDB has insufficient energy absorption for this test configuration Neon / LCMDB Neon / Modified LCMDB Estimate LCMDB 3362 Neon

Modified Estimate Mod LCMDB 3608 Neon

50

25

0

-25 K I LO M ETE R S / HOUR

-50

0.00 0.01 0.02 0.03 0.04 0.05 0.06 0.07 0.08 0.09 0.10 0.11 0.12 0.13 Time in Seconds

TotalForce Estimate = MassMdb Estimate LCMDB 3413 Caravan

Modified Estimate Mod LCMDB 3609 Caravan

50

25

0

-25 K I L O M ETE R S / HOUR

-50

0.00 0.01 0.02 0.03 0.04 0.05 0.06 0.07 0.08 0.09 0.10 0.11 0.12 0.13 Time in Seconds Neon / Modified LCMDB

Test 3608, Neon / Mod LCMDB

3000 315.0

2500 2500 2000

1500 2000 1000

500 I m pu l se ( N - s)

1500 0

400 -500

1000 500 Height in mm -0

600 500

500 Distance from Center 0 700 Neon / LCMDB

Test 3362

1500 315.0

2500

2000

1000 1500

1000

500 I m pu l se ( N - s)

0

500 400 -500

500 Height in mm -0

600

0

500 Distance from Center 700

Presence of the LCMDB bumper substantially shifted the load distribution Caravan / Modified LCMDB

Test 3609

1000 315.0

1250

750 1000

750

500

250 I m pu l se ( N - s) 500 0

400 -500

500 250 Height in mm -0

600

0 500 Distance from Center 700 Caravan / LCMDB

Test 3413

1250 315.0

1250 1000 1000

750

500 750

250 I m pu l se ( N - s)

0

500 400 -500

500 Height in mm -0

250 600

500 0 Distance from Center 700

Even for the Caravan tests, the LCMDB bumper substantially changed the load distribution Conclusions

• Compatibility continues to be a concern for US fleetwide safety • MDB crash tests can reasonably replicate vehicle to vehicle crashes • Load distribution is sensitive to the design of the MDB face – Still need to establish the relationship, if possible, between load distribution and compatibility – Work in progress to reevaluate MDB design to represent average or most likely collision partner