Buckling-dominated irregular curved-wall origami for high-efficiency energy absorption

Curved-wall origami (CWO) structures exhibit intrinsic elastic behavior arising from coupled crease folding and panel bending and offer a lightweight route for energy absorption. However, conventional CWO designs rely on predefined crease patterns and often suffer premature global instability, limiting stable progressive collapse and energy-absorption efficiency. Inspired by the irregular walls of cuttlebone, this study introduces controlled geometric irregularity and proposes an irregular curved-wall origami (ICWO) that reprograms curvature distributions to regulate instability evolution. An analytical model is first developed to describe the entire compression process of ICWO, linking the load response to curvature features and instability evolution. Quasi-static experiments and finite element analyses show that ICWO suppresses premature collapse and activates local buckling modes, enabling a stable progressive deformation pathway in which energy dissipation is governed by buckling evolution. A buckling-load response surface quantifies curvature-driven transitions among dominant buckling modes. Machine learning is further leveraged to explore the ICWO design space and maximize energy-absorption efficiency, with experiments confirming a maximum increase of 108 % in specific energy absorption (SEA) over regular counterparts. Moreover, this work provides a new paradigm for metamaterial design based on curved-wall origami. The geometric regularity-breaking greatly expands the design space of origami, creating new opportunities for origami-inspired metamaterials.