Development of Aluminum Hood Structure for Pedestrian Protection

This paper presents a new type of aluminum hood structure that is suitable for pedestrian protection and weight reduction. With a pedestrian head impact, the energy absorption of an aluminum hood is smaller than of a steel hood, given the same structure and an increase in thickness to maintain stiffness. Therefore, an aluminum hood with a beam type structure, as is seen with steel hoods, needs a larger space between the hood and parts in the engine compartment to reduce head injury. Using finite element analysis, we confirmed that a new type of aluminum hood with a wave shaped cross section is able to absorb more energy in a smaller space than the beam-type aluminum hood. As shown in head impact tests, the HIC value of the new type of aluminum hood is improved by avoiding hard impacts with the parts in the engine compartment.