Assessment of the pedestrian protection performance of a sandwich hood with architected lattice cores

Pyramidal lattice composite structure possesses an excellent behaviour of ultra-low density, high stiffness and strength together with the advantage of multifunctionality, which could be promising for vehicle lightweight applications. In this study, a sandwich structured engine hood was proposed which comprises outer and inner steel panels together with a composite pyramidal lattice structure core (Fig.1). The pyramidal lattice core could be manufactured by slot assembly of strips cutting from flax fibre reinforced laminates. The pedestrian protection capability of engine hood was evaluated in finite element method. The architected pyramidal lattice sandwich structure in this study is proven to be feasible for a sandwich engine hood that could meet the Euro-NCAP HIC threshold of 1000. Moreover, the present study provides a good reference of lattice structures to similar application on car body panels with complex curvature.