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Numerical investigation on automotive bumper structure improvements for pedestrian protection

ABSTRACT Vehicle bumper design remains a key automotive engineering design challenge for ensuring pedestrian safety in car accidents. In this study, a three-dimensional finite-element lower legform is simulated and validated using static and dynamic tests according to three main criteria, namely, the upper tibia acceleration, knee shearing displacement and bending angle. Important design parameters such as material, thickness and location of different parts of the front vehicle structure were studied. The lower legform and dynamic impactor were simulated in LS-DYNA according to European commission (EC) regulation No 631/2009. Then, the legform and a Class-B car front bumper were used in collision tests at three different distances from the bumper centre point. Finally, the design was optimised in order to meet all requirements of the EC regulation related to vehicle pedestrian collision tests, and an improved bumper model which guarantees complete pedestrian protection is presented and discussed along with guidelines which can have significant applications in the design of pedestrian-friendly bumper structure components.