Effect of Sinusoidal Double-Curvature Geometry on Axial Crushing and Energy Absorption of Crash Box

Abstract
This study conducts a comprehensive parametric analysis of the new origami-inspired feature with sinusoidal double curvature (SDC) to identify the most effective geometric variables for enhancing the crashworthiness of the vehicle's crash box. To achieve this, two identical crash boxes were removed from a small car and tested under compressive loading to determine their energy absorption (EA) and establish realistic boundary conditions for the finite element analysis (FEA).
The verification study demonstrates a strong correlation between the numerical analysis and experimental findings, with minimal deviation in energy absorption. Hence, the validated FE boundary conditions were used in the parametric study for further analysis at different velocity impact tests. It was concluded that the number of sinusoidal creases on the SDC’s cross-section increased EA by up to +21.13%. Also, adding sinusoidal folds along the height of the SDC crash box (Z-axis) produced the largest positive deviation in EA, with a difference of +21.97% compared with the experimental benchmark. The crash behaviour of the symmetric features showed a modest 10.7% improvement over the asymmetric sinusoidal shape along the length (X-axis) of the SDC, confirming that the symmetric SDC exhibits uniform deformation and reduces stress concentrations of the SDC’s crash box.