Fig. 2: The designed origami element and constructed functional group.
a The crease pattern and 3D schematic of designed origami element. The base with three classes of facets is displayed in the left red dashed box. Each kind of creases are displayed in the right red dashed box. The black arrow points the axial direction of the element. Symbols φi represent the independent angle parameter of the origami element, and i corresponds to the crease 1, 2, 3, and 4. Hmax represents the maximal height of the designed origami element. b The physical demonstration of expansion and contraction tendency of crease segments under different initial dihedrals (example: crease 4). The facets with high stiffness are manufactured using photosensitive resin by light curing three-dimensional (3D) printing technique for mechanical testing. Creases with representative angles are produced through fused deposition modeling 3D printing technique of thermoplastic polyurethane (TPU) with a hardness of 95 A. See Supplementary Movie 9 and “Methods” for the details about origami element fabrication and assembly. c The snapshots and mechanical responses of the CI, CII, CIII, and R elements. The deformable modes of origami elements from left to right are full-length tension (CI), partial-length tension and compression (CII), full-length compression (CIII), and full-length compression with a static bifurcation behavior (R). The snapshots display the physical prototypes of origami element in stable state and maximum deformation state. The selected initial dihedral angle for creases of the physical prototype is listed in Supplementary Fig. 13b and the side length l of the physical prototype is 110 mm. The error bars present the upper and lower limits of stress for multiple experimental subjects testing. Hstable represents the structural height of designed origami element at stable state. Source data are provided as a Source Data file. d The prototype demonstration and transformation schematic of CI, CII, CIII, and R functional group constructed by one C (CI, CII, or CIII) element and one R element shown in (c). The white arrow indicates the deformable direction of the functional group.
