Designing for head impact safety using a combination of lumped parameter and finite element modeling

Abstract

Abstract The current paper describes an improved lumped parameter model with a mass and a nonlinear spring that can be useful in vehicle crash safety design. The area of vehicle upper interior headform impact is chosen here for the purpose of illustration. The improvement in lumped parameter modeling stems from the piecewise linear representation of unloading force vs. displacement curves of arbitrary shapes. Available test results and responses from a finite element model with a featureless Hybrid 3 headform that has been developed for the current study are used for ascertaining the efficacy of the lumped parameter model with modified unloading behavior. The comparisons indicate extremely good predictability of test and finite element-based headform responses and HIC (d) with the present improved lumped parameter model. Finally, a new hybrid approach is illustrated for obtaining an optimized head impact countermeasure design using a combination of finite element and lumped parameter modeling.