Safety-critical Optimization of Vehicle Parts

Abstract

In recent years, automotive weight reduction has attracted considerable attention due to its benefits in fuel consumption, emissions, material usage, and vehicle dynamics. For unsprung masses, these effects are particularly pronounced, directly influencing vehicle stability, maneuverability, and road safety. Conventional engineering optimization is typically based on static load cases; however, such "simple" optimization is insufficient for safety-critical components operating under real service conditions.
In practice, automotive components are exposed to dynamically varying, stochastic loads originating from road excitation, and their failure is therefore predominantly governed by fatigue rather than static strength. Current engineering optimization tools do not yet enable direct optimization with respect to fatigue life. To address this limitation, a dynamic factor is introduced to represent time-dependent loading effects within the optimization framework. The optimization problem is reformulated with the explicit constraint that the original safety factor must not decrease, ensuring that the expected service life of the component is preserved.
The results indicate that, although the achievable mass reduction is smaller than that obtained by purely static optimization, it remains significant while maintaining fatigue-related safety margins. The applied approach is restricted to geometry modifications compatible with conventional manufacturing, ensuring industrial relevance.