Sensitivity of the WorldSID 50th and ES-2re Thoraces to Loading Configuration

Abstract

An ideal injury criterion should be predictive of the risk of injury across the range of loading conditions where it may be applied. The injury risk curve associated with this criterion should be applicable to all loading conditions. With respect to side impact, the injury risk curve should apply to pure lateral or oblique loading by rigid and padded walls, as well as airbags. Trosseille et al. (2009) reported that the number of fractured ribs was higher in pure lateral impact than in forward oblique interaction with an airbag. A good dummy criterion should be able to account for this difference. To evaluate various injury criteria with the WorldSID 50 th and ES-2re dummies, the dummies were exposed to the same airbag loadings as the PMHS. The criteria measured in the dummy tests were paired with the rib fractures from the PMHS tests. Regarding the effect of configuration, results of sled tests with the 50 th percentile WorldSID (Petitjean, 2009) and ES-2re (Kuppa, 2003) have been paired with injuries found in the PMHS tested in the same conditions. The relationships obtained were compared with the relationships established in the same way for the subjects loaded in the airbag tests. Comparing the lateral and oblique lateral loading conditions, both the WorldSID and the ES-2re exhibited differences in peak lateral deflection of their ribs that were consistent with the different number of rib fractures for PMHS subjected to these loading conditions. For each dummy, the risk of rib fractures could be assessed from one injury risk curve, regardless of the loading angle. Furthermore, the same injury risk curve can be used to assess the risk of rib fractures from sled tests and airbag loading. However, because the WorldSID deflection measurements differed in the rigid and padded sled tests, it is recommended that the dummy's sensitivity to padding be further assessed prior to adopting injury risk curves for WorldSID. Rib deflections of the ES- 2re were not sensitive to padding. Finally, VC should not be considered as a valid criterion to assess the risk of rib fractures.