Robustness Optimization of a Vehicle Suspension Durability Using Multibody Simulation

Product designers worldwide are confronted with highly competitive though conflicting demands to deliver more complex products with increased quality in ever shorter development cycles. Optimizing design performance with purely test-based approaches is no longer an option and numerical simulation methods are widely used to model, assess and improve the product design based on virtual prototypes. However, variability in design parameters and in operating conditions leads to scatter in actual performances and must be incorporated in the simulation process to guarantee the robustness of the design.

This paper presents the application of state-of-the-art robust design techniques to a vehicle suspension system. A multibody model of a vehicle with a virtual test ground has been created to predict the durability response of three main components of the suspension system. These components have been made flexible to assess the effect of variability in geometrical and material characteristics on the robustness of the durability performance. The results of the robustness assessment have been used to improve the durability performance of the suspension and reduce the scattering in the output quantities of interest.

With the robust design methodology, engineers can obtain a better understanding of the effect of variability sources by including noise, signal and control factors directly into the design loop. Based on the analysis results, the robustness of the design can be assessed and improved if needed.