Design optimization by response surface methodology : application to crashworthiness design of vehicle structures

Standards imposed by certification regulations are very strict and the requirements of the customer in terms of vehicle safety are always increasing. It is often necessary to redesign several vehicle components in order to achieve a global better performance. Design optimization by response surface methodology has been effectively used to improve the mechanical behaviour of several automotive components in impact load conditions. An iterative optimization algorithm based on a multipoint approximation scheme and on the steepest descent method has been used to identify the best geometrical configuration of several energy absorbing devices. Load uniformity parameter LU defined as the ratio between the maximum and the mean crushing forces has been used as objective function. Three design cases have been analysed and the results of the optimization process are shown.