Side Oblique Injury Criterion

Previous analysis of CIREN and NASS data indicate the prevalence of anterior lateral loading to the occupant in side impact crashes. Numerous studies have examined the post mortem human subject (PMHS) response to pure lateral loading; however, the biomechanics of anterior lateral loads to the thorax are not well understood. The goal of this study is to develop a side oblique injury criterion and biofidelity requirements for modern side impact anthropomorphic test devices (ATD). The surrogates were seated on a side impact buck with angled thorax and abdomen plates. Lateral acceleration to the buck was applied using either a deceleration-rebound sled or acceleration servo-sled with a 6.7 m/s deltaV. Chestbands placed at the axilla, mid-sternum, and lower sternum/abdomen were used to calculate the magnitude and direction of chest displacement. The direction of maximum displacement was quantified as an angle relative to a vector between the spine and sternum to yield a measure of the obliquity of applied force. PMHS Displacement data were mass scaled to 50% male subject and compared to ES2-re, Thor NT, and WorldSID. The average maximum deflection for the PMHS oblique tests was 84.0 mm (38.0% higher than pure lateral) and an increase in the average number of rib fractures (9.3 vs. 7.0) and MAIS (3.5 vs. 2.0). The average maximum chest deflection response angle for the oblique tests was 73.1 degrees. For the ATD’s the ES-RE had an average maximum deflection of 48.5 mm and response angle of 90.6 degrees, WorldSID was 83.3 mm and 87.8 degrees, and Thor NT was 60.0 mm and 91.5 degrees. Results indicate the potential for more severe injuries with anterior oblique loads and the varied response of ATD’s to this input.