Moving Deformable Barrier Test Procedure for Evaluating Small Overlap/Oblique Crashes 2012-01-0577

In September 2009 the National Highway Traffic Safety Administration (NHTSA) published a report that investigated the incidence of fatalities to belted non-ejected occupants in frontal crashes involving late-model vehicles. The report concluded that after exceedingly severe crashes, the largest number of fatalities occurred in crashes involving poor structural engagement between the vehicle and its collision partner, present in crashes characterized as corner impacts, oblique crashes, impacts with narrow objects, and heavy vehicle underrides. By contrast, few if any of these 122 fatal crashes were full-frontal or offset-frontal impacts with good structural engagement, excepting crashes that were of extreme severity or the occupants that were exceptionally vulnerable.

The intent of this research program is to develop a test protocol that replicates real-world injury potential in small overlap impacts (SOI) and oblique offset impacts (Oblique) in motor vehicle crashes. Previous work towards this goal has led to the development of a Research Moving Deformable Barrier-to-Vehicle (RMDBtV) test protocol, which is further evaluated in this paper. While there were some inherent differences in the Vehicle-to-Vehicle (VtV) and RMDBtV test results, the overall agreement of vehicle and occupant responses proved promising enough to perform another VtV to RMDBtV comparison. As in the previous study, the first step is to compare the RMDBtV to VtV test for the same vehicle. This comparison focuses on the target vehicle crash metrics (pulse shape, average deceleration, slope of the velocity time-history, total change in velocity, exterior crush profile, and interior intrusion) as well as occupant kinematics and injury assessment values.

The second step of this research program is to assess the performance of new vehicles in the SOI RMDBtV and the Oblique RMDBtV test procedures. This research will provide insight on the ability of these two test procedures to replicate vehicle and occupant response as seen in the field. This paper presents the results of 7 different 2010-2011 model year vehicles tested in both the SOI and the Oblique test procedures. In these tests the overlap and RMDB closing speed was held constant for both procedures. The vehicle response demonstrated a decreasing trend of delta-V and longitudinal acceleration with increasing vehicle mass, but the trend did not hold for lateral acceleration. Aside from the lightest vehicle showing the largest magnitude of intrusion, there was no apparent trend of vehicle mass with intrusion. The occupant kinematics demonstrated head contact locations that are common in the field, torso loading of the restraint system and steering wheel, and a distribution of injury assessment values that is representative of the field injury risk.