Deployable architected instability-based metamaterials through thickness-accommodating kirigami folding method

• Integrate thick-panel kirigami to fold and deploy AIMs. • Enable compact stowage and reversible large deformation. • Demonstrate the folding method on AIMs consist of regular polygon units. • Preserve mechanical performance after deployment. Conventional energy absorption devices dissipate impact energy through irreversible plastic deformation, limiting them for single use. While architected instability-based metamaterials (AIMs) offer reusability by using reversible multistable mechanics, they require larger surface footprint than conventional absorbers when designed to dissipate the same impact. This makes compact stowage a critical challenge, especially for space and aerospace systems with tight space constraints. We therefore present foldable AIMs using kirigami-inspired rigid folding strategies, enabling both reusability and deployability. They are folded into a compact volume for transportation and expanded into a functional metamaterial for energy absorption and impact mitigation at the destination. Foldable AIMs are constructed from tessellations of identical regular shapes, such as equilateral triangular, square, and regular hexagonal unit cells, connected using a Hamiltonian circuit approach and locked at the hinges in their deployed states. The mechanical performance of the deployed AIMs is evaluated using finite element analysis and experiments. The deployable AIMs exhibit mechanical behavior comparable to that of conventional AIMs fabricated as monolithic structures. This study introduces a generalizable approach that incorporates deployability to metamaterials without compromising their original exceptional functions.