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Impact and injury patterns in side crashes of vehicles with good ratings for side crash protection. SAE Government Industry Meeting Washington, DC ● January 25, 2012. Becky Mueller Research Engineer. Side impact crashworthiness evaluations. Moving deformable barrier crash tests
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Impact and injury patterns inside crashes of vehicles with good ratings for side crash protection SAE Government Industry Meeting Washington, DC ● January 25, 2012 Becky Mueller Research Engineer
Side impact crashworthiness evaluations Moving deformable barrier crash tests 3,300 lb. barrier at 50 km/h M vehicles tested are rated GOOD ACCEPTABLE MARGINAL POOR head protection injury measures from SID IIs dummies G A P structure
Side impact crash protection ratings Improvements: 2003 to 2011
Risk of dying in a side crash based on rating Drivers in good rated vehicles were 70% less likely to die in a left side crash than drivers in poor rated vehicles*. (Teoh and Lund, 2011) * Of vehicles with standard head and torso airbag protection
How are people being seriously injured in vehicles designed for good side crashworthiness? NASS Query: • Side crashes with designation: L (8,9,10) or R (2,3,4) • Case years 2000-2010 • AIS 3+ or fatally injured occupants • All vehicles with good IIHS side rating • 51 vehicles met these criteria • 56 total occupants (multiple qualifying occupants in 5 case vehicles)
Occupant location relative to impact 19 occupants 37 occupants Farside Nearside Direction of Impact
Farside occupant characteristics 19 farside occupants are not evaluated in any current crashworthiness evaluation test • High levels of occupant compartment intrusion • Occupant motion inboard toward intruding structure Ford 4 point safety belt concept
Center airbag Control occupantkinematics infarside crashes Also address headinjuries from other occupant contact (seen in 4 cases) center airbag will debut in 2013 ChevroletTraverse/GMC Acadia/Buick Enclave
Nearside case vehicles 2004 -10 model year vehicles 27% of all vehicles rated Good
Crash scenario – vehicle-to-vehicle 25 intersection style crashes Average occupant age: 49 years old 6 (24%) fatally injured occupants Two large truck partner vehicles excluded
Crash scenario – stationary object 12 loss of control crashes Average occupant age: 27 years old 9 (75%) fatally injured occupants
Stationary object crash test NHTSA side pole test • 32 km/h impact with rigidnarrow pole • Rating based on dummy sensors
Crash severity Percent of cases by lateral delta V (km/h) IIHS side impact test delta V
Crush values Percent of cases with by maximum crush (cm) IIHS Good rated side impact test maximum crush NHTSA pole test maximum crush
Airbag non-deployment Lower severity with loading primarily forward of occupant compartment 48 year old male driver Struck by 2006 Honda Accord Delta V: 35 km/h Facial fractures from b-pillar Rib fractures from door interior trim
Airbag late deployment – seen in tests At higher severities, curtain airbags may not have time to properly deploy for adequate protection
Airbag late deployment – seen in real world 2007 Nissan Versa Max crush: 19 cm 29 year old male belted driver Lost control and struck light post Fatal head injuries from direct contact with post Difficult to identify in crash reconstructionsince airbag does eventually deploy
Summary • Farside occupants (33% of cases) not addressed by crash testing • IIHS and NHTSA tests are addressing relevant crash modes • Twice as many vehicle-to-vehicle crashes as stationary object • Vehicle-to-vehicle crashes: lower severity, involved older occupants • Fixed object crashes: higher severity, involved younger occupants • LTV underrepresented in case vehicles, overrepresented in striking vehicles • Airbag deployment issues contributing to injuries
Future work Investigate further how occupants are getting injured in cases with similar severity to IIHS and NHTSA tests
Airbag late deployment – torso airbag At higher severities, torso airbags may not have time to properly deploy as door trim intrudes