Abstract: Novel mechanical metamaterial structures usually consist of a number of simple cells combined by three-dimensional regular arrays. Due to their extraordinary physical properties, these mechanical metamaterial structures often have the advantages of light weight, high strength, multi-stability, excellent energy absorption capability, etc., and are becoming a research focus in many fields. In order to further enrich metamaterial structures, more high-quality cellular structures need to be explored. Origami structure has the advantages of simple structure and easy folding, which provides an important way to construct metamaterial cells. In this paper, a twofold-symmetric kirigami (Twofold-sym Kiri) pattern with good symmetry is adopted, and a cell with negative Poisson's ratio and single degree of freedom folding is proposed. By analyzing the influence of the geometric parameters of the cell structure on the folding motion, it is found that the cell has a stretching characteristic, namely negative Poisson's ratio. When the variable γ of the kirigami pattern approaches 0, the cell tends to the classical reentrant honeycomb structure. Compared to the classical reentrant honeycomb structure, the proposed cell has the advantage of single DOF which will benefit to construct large deployable energy-absorption structures quickly. With the usage of the self-locking function caused by the physical interference during folding, the cellular structure in the folding limit state has the load capacity. Through the static compression test, it is found that the Twofold-sym Kiri structure has better load capacity than the reentrant honeycomb structure, which is an excellent origami metamaterial structure. The proposed cell provides the possibility for exploring more new metamaterial structures and lays the theoretical analysis foundation for it.

Key words: kirigami pattern, twofold-symmetric Bricard 6R linkage, negative Poisson's ratio, metamaterial structure