Experimental validation of an automotive subframe stiffener plate design obtained from topology optimisation

High performances are indispensable elements for automotive subframe design to improve automotive ride comfort and handling stability. In view of its multiple functions, the essential performances for subframe design include stiffness, natural frequency as well as weight, especially stiffness referred to as the fundamental target. This paper presents a validation process for an automotive subframe stiffener plate with innovated design obtained from topology optimisation through both numerical simulations and experimental measurements. An optimised configuration of the stiffener plate is proposed through structural topology optimisation that improves the stiffness and lightweight requirement. The final detailed geometry is reconstructed in consideration of manufacturing requirements including welding procedure and assembly layout. The natural frequencies of the optimised model are analysed through experimental measurement and numerical simulation. The results demonstrate that the proposed approach is an efficient and effective methodology for subframe stiffener plate design to improve its stiffness, and with the conclusion that the numerical simulation can to some extent replace the experimental measurement for modal analysis.