Experiments and design of a kirigami-based multi-stage energy absorption structure subjected to axial impact

As a typical energy-absorbing structure, the thin-walled structure dissipates impact energy through the formation of plastic hinges and material failure. The geometric configuration of the energy-absorbing structure deeply influences its response to impact loads. For a certain load curve required by collision scenarios, this study proposes a novel design method for approximating a continuous impact load curve with discretized ones. Based on kirigami structures, the conceptual framework integrates multi-module and multi-stage designs to regulate segmental stiffness through theoretical analysis, thereby achieving the desired curve approximation. The effectiveness of the proposed kirigami-based multi-stage energy absorption structure (KMS) is validated by drop-weight impact tests and numerical simulations. Findings demonstrate that the KMS effectively dissipates impact energy in a progressive manner, aligning with the desired load curve and inducing stable and orderly structural deformation under axial impact. Through appropriate parameter design, the deformation mode and the inducing effect of the kirigami structure can be managed, enabling the structure's adaptability to diverse collision scenarios.