In this study, we first present a comparison between pelvis/upper leg injuries observed in real-world accidents as recorded in the database of the Medical University of Hanover, and the EEVC test results of corresponding cars as published by EuroNCAP. The fact that modern cars with rounded hood edges cause very few pelvis/upper leg injuries is discussed against the findings of the EEVC tests, where these cars do not perform significantly better than their older counterparts with sharper hood leading edges. This discrepancy could be due to the fact that the radius of the hood edge is not accounted for in the current version of the test protocol. In a second step, various impacts against several different simplified hood shapes were simulated using a detailed finite element model of a 50th percentile male pedestrian. The finite element model (THUMS) has been extensively validated against PMHS experiments in previous studies. The validated model affords detailed insight into pelvic and femoral deformations and loading patterns, and reveals, as expected, that the shape of the hood leading edge plays a critical role in the resulting biomechanical loading patterns. Based upon the results of this study, recommendations are offered for a more appropriate characterization of the hood shape with regard to pelvis/upper leg injury risk. (Author/publisher)
Abstract