Rigid origami is a special type of origami, which has attracted more and more attention from mathematicians, scientists and engineers as there is no deformation of panels during the continuous folding process. Mathematicians concur that it is impossible to fold the sealed polyhedron rigidly, and the recent research is about the box-shaped structure without top cover. Therefore, one of the challenges is to compactly fold flat a sealed polyhedron made from rigid facets with a single degree of freedom. It is possible to solve this challenge by introducing one diagonal incision on the facet of the polyhedron.
       Dr. Yuanqing Gu and Prof. Yan Chen of the Department of Mechanical Engineering, Tianjin University, proposed a new method, namely by adding diagonal creases and one incision to the non-rigid crease pattern, to design origami cubes with rigid foldability, flat foldability, and one degree of freedom (DOF). A total of four cases of crease patterns that enable origami cubes with distinct folding performances have been designed, which covers all possible layouts of the diagonal creases on the square facets of origami cubes. Based on the kinematic equivalence between the rigid origami and the spherical linkages, the corresponding spherical linkage loops are introduced and analysed to reveal the motion properties of four origami cubes. The newly found method can be readily utilized to design deployable structures for various engineering applications including cube-shaped cartons, small satellites, containers, etc.

4R-5R-4R-5R Origami Cube

4R-4R-5R-5R Origami Cube

4R-4R-4R-6R Origami Cube

5R-4R-5R-4R Origami Cube

        The work was accepted by International Journal of Solids and Structures on Sept. 8, 2020 and published online on Oct. 6.

Yuanqing Gu, Yan Chen, 2020, Origami cubes with one-DOF rigid and flat foldability, International Journal of Solids and Structures, 207, 250-261.
(https://doi.org/10.1016/j.ijsolstr.2020.09.008)