FIGURE 2.

A single-layer Yoshimura-ori structure and the theoretical strain change of the crease $\overline{P_1{B}_1}$. (A) A single-layer Yoshimura-ori structure. The shaded area represents a rectangle “unit” to be studied. (B) Top-down view of the structure. The origin of the O-xyz coordinate system locates at the centroid of the equilateral triangle $\overline{C_1{C}_2{C}_3}$, the x-axis is chosen to intersect vertex $C_1$, the z-axis is the rotational axis that is perpendicular to the plane $\overline{C_1{C}_2{C}_3}$, and the y-axis follows the right-hand rule convention. The reflectional and rotational symmetry of the structure is also indicated. (C) Theoretical strain in P ₁ B ₁ as a function of the height $h$.