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This paper demonstrates how to use advanced finite element modeling techniques such as airbag modeling, material plasticity with consideration of failure and effects of temperature and strain rates, surface to surface sliding contact treatment, nonlinear transient dynamics, and so on, to perform structural analysis of airbag modules. A technique to calculate the transient dynamic loads on the structure of an airbag module is first demonstrated. The dynamic transient loads on the structure are calculated by an integrated airbag modeling and sliding contact treatment with the structural model of the airbag module. Other techniques for modeling special design features of the airbag module, such as tear seam, tear tie, and hinge on a cover, press fit of a gas defuser, housing, connections of each component, and so on are also illustrated and discussed. All modeling techniques are illustrated by analysis examples in product development.

The FMVSS 201 regulation requires that interior components in upper compartment of a passenger vehicle pass a head impact test using a Free Moving Head (FMH) model with a HIC(d) limit. In this type of test, most interior components themselves do not generate high HIC(d) numbers but the steel structures underneath these components do. In addition to normal functions, interior components need to absorb the kinetic energy of the FMH model such that the acceleration response of the FMH model does not generate a high HIC(d) number in the test. This paper first reviews the existing work on the principles for the head impact protection and identifies limitations of the existing theory for the design of the interior components that are mounted on flexible structures. This paper discusses and proposes a design methodology for automotive interior components to ensure that they comply with FMVSS 201 head impact requirements.