Predictions of occupant injury using explicit finite element crash simulations may be enhanced by including numerical representation of materials that are not normally included within the structural model. Intuitively, it makes sense that the carpet would be useful to predict the tibia index during frontal crash events; however, there appears to be little published on the topic. The tibia index is an injury criteria that needs to be predicted during the Insurance Institute for Highway Safety (IIHS) frontal offset occupant simulations, but may also be looked at during unbelted Federal Motor Vehicle Safety Standard (FMVSS) 208 simulations. Since carpet behaves quite differently during compressive and tensile loading, a numerical representation that can stably capture both regimes during occupant modelling is needed.This paper outlines a method to model the carpet using a specific meshing method and two material models. Shell elements in combination with a piecewise linear plasticity material model are used to model the tensile load carrying capacity of the carpet, while brick elements and a foam material model are used to represent the compressibility of the carpet. Validation of using this modelling method with test data is presented, as well as the application of the carpet model in larger occupant models.
Article of Honda R&D Technical Review Vol.20 No.1 (163 - 170)