Numerical assessment of the impact of vehicle body stiffness on handling performance

This paper investigates the problem of how to use Computer-Aided Engineering (CAE) tools to properly assess the influence of vehicle body stiffness on handling performance. One of the challenges in this context is related to the accuracy of the Body-In-White (BIW) model. The amount of degrees of freedom should be minimal without losing the necessary accuracy, especially for local stiffness modifications. A technique for this is proposed that uses Component Mode Synthesis (CMS) methods to reduce a Finite Element (FE) model of a BIW. The resulting reduced model of the BIW is then used in flexible Multibody (MB) simulations of handling manoeuvres in order to investigate the influence of a changing body stiffness. For the objective handling evaluation, conventional metrics are assessed. However, because these metrics only show small differences for various body stiffnesses, also other quantities, such as body deformation, are proposed as a clearer indicator of the influence of vehicle body stiffness on handling performance.