Mathematical design of electric vehicle impact attenuators: Metallic vs composite material

Electric vehicle energy consumption may be minimized redesigning specific car parts in order to not compromise crashworthiness aspects. Although more challenging compared with metallic counterparts because of their microstructural heterogeneity and behavioral sophistication, composite materials seem to be the best solution due to high specific strength and energy absorption. Differently from traditional shape, electric vehicle may be equipped with frontal impact attenuator whose geometry is very similar to the square frusta adopted for racing cars. The paper aims at developing an analytical procedure in order to capture the energy absorption capability of square impact attenuators with a square frusta geometry. Both metallic and composite materials are analysed in order to save the body weight. An energetic approach is addressed taking into account the energy contributions responsible for the absorption during crushing. Comparing the metallic and the composite model introduced, the best configuration of an electric vehicle specific frontal impact attenuator able to absorb a fixed impact energy is obtained.