Exploration of the stiffness profiles of modern cars in pedestrian impacts

Abstract

Consumer and regulatory tests for improvement in pedestrian protection are now firmly established. A change in the vehicle frontal stiffness profiles as a result of these tests is less well established. The purpose of this paper is to contribute to the knowledge base on the vehicle frontal stiffness in pedestrian impacts. Using data recorded as part of the European New Car Assessment Programme, a series of 139 impact tests using headform and legform impactors were used to calculate the vehicle frontal stiffness profile of eight cars manufactured between 2006 and 2010. To account for one of the limitations of the legform as a device for measuring the stiffness of a surface, a methodology for determining a correction factor using the multi-body modelling software MADYMO is presented. Comparison with previous published work showed that the stiffness of the windscreen was unchanged, but that the stiffnesses of the bonnet and front bumper were reduced.