Energy absorption characteristics of origami-folded thin-walled square tubes internally filled with graded polyurethane foam structures

Rigid polyurethane foam, known for its low density, lightweight, and excellent energy absorption properties, has been effectively employed to enhance the energy absorption capacity of origami-folded thin-walled square tubes filled with graded foam. In this study, quasi-static compression experiments and finite element simulations were conducted on 3D-printed origami-folded thin-walled tubes filled with graded foam. The impact of factors such as the number of folding layers, interlayer dihedral angles, wall thickness, and various foam densities on the energy absorption characteristics of these thin-walled tubes was analyzed. It was found that the incorporation of fold designs significantly improved the energy absorption properties of thin-walled tubes. Notably, origami tubes filled with positively graded foam outperform their negatively graded and single-density foam-filled counterparts in terms of energy absorption capability. The research underscores the excellent energy absorption properties of origami-folded thin-walled square tubes filled with graded foam, offering valuable insights for optimizing structures involving more intricate origami patterns and subsequent graded foam filling.Keywords