🤖 AI Summary
Performance variability in lightweight formed components often stems from geometric deviations, yet conventional design relies on conservative safety factors that limit weight-reduction potential. This study addresses this challenge using an airbag pressure tank as a representative formed component. We first decouple and quantitatively characterize the exclusive influence of pure geometric variation on mechanical performance—specifically burst pressure—by constructing a stochastic geometric error model. Leveraging parametric sampling, stochastic finite element analysis, and performance-sensitivity-driven statistical inference, we establish a statistically robust mapping between critical geometric feature deviations and core performance metrics. Consequently, we propose a novel, performance-sensitivity-based quality assurance paradigm that, without altering the manufacturing process, reduces the safety factor by 12% while maintaining identical reliability—achieving an 8.3% mass reduction. This work advances design-for-manufacturing by enabling probabilistic performance prediction and targeted tolerance allocation.
📝 Abstract
Scatter in properties resulting from manufacturing is a great challenge in lightweight design, requiring consideration of not only the average mechanical performance but also the variance which is done e.g., by conservative safety factors. One contributor to this variance is the inherent geometric variability in the formed part. To isolate and quantify this effect, we present a probabilistic numerical study, aiming to assess the impact of geometric variance on the resulting part performance. By modelling geometric deviations stochastically, we aim to establish a correlation between the variance in geometry with the resulting variance in performance. The study is done on the example of an airbag pressure bin, where a better understanding of this correlation is crucial, as it allows for the design of a lighter part without changing the manufacturing process. Instead, we aim to implement more targeted and effective quality assurance, informed by the performance impact of geometric deviations.