Injury analysis of real-world small overlap and oblique frontal crashes

Recent research has indicated poor injury outcomes for front row occupants of passenger vehicles equipped with frontal air bags when the longitudinal frame rail(s) are missed by the struck object. The objective of this research was to establish key factors for injury causation from a uniform manual analysis of real world crashes where very limited or no engagement of the longitudinal structures occurred. A multidisciplinary team of experts at the National Highway Traffic Safety Administration NHTSA) was assembled to review the available real-world cases matching this crash profile. The NHTSA team utilized a uniform process to review all cases to ensure the same data points were evaluated by each team member. Regular meetings were held by the team to discuss cases and to keep the reviews uniform. More than 380 cases were extracted from the National Automotive Sampling System-Crashworthiness Data System (NASS-CDS) and the Crash Injury Research and Engineering Network (CIREN) for analysis. Injuries to the thorax and pelvis were the most prevalent, and oblique loading played a role in thoracic and head injury causation. The cases reviewed demonstrated possible issues with air bag coverage of contact points, intrusion contributing to injury, and occupant lower extremity kinematics associated with crash obliquity influencing pelvic fractures. The final result of the reviews was to initiate a vehicle crash research plan to test the feasibility of recreating the real-world crash and kinematic responses seen during the case reviews. The results of these case reviews indicate opportunities for improved anthropomorphic test device (ATD) response to duplicate the crash outcomes seen in this research.