Structural Optimization and Torsional Rigidity Analysis of an AISI 1018 Steel Space-Frame Chassis for SUPRA SAE Competitions

Objective: The primary goal of this study was the structural validation and torsional optimization of a tubular space-frame chassis for SUPRA SAE competitions. Methodology: Using Autodesk Fusion 360 for iterative CAD modeling and SimScale for cloud-native Finite Element Analysis (FEA), the design focused on integrating suspension hardpoints into a fully triangulated AISI 1018 steel structure. Results: Ten design iterations were performed, transitioning from a rectangular to a pentagonal roll hoop geometry. Torsional rigidity was quantified by applying a 275 Nm torque couple, resulting in a maximum vertical displacement of 0.58204 mm. This corresponds to a final torsional stiffness of 2,267.63 Nm/deg—a 22.7% improvement over the initial design—while maintaining a constant chassis mass of approximately 35.48 kg. Conclusion: Impact simulations (Front 6G, Side 4G, Rear 6G) confirmed structural integrity with a minimum Factor of Safety (FoS) of 1.602, ensuring compliance with global safety regulations.