Recessed pyramid origami module and its tessellation

Origami is a technique of folding a sheet along patterns, allowing the shape, size, or mechanical properties to be changed. Its ability to compactly fold and then deploy into a large size is widely exploited in space structures, including solar panels, space architecture, and so on. Especially, for 3D foldable structures like space shelters, thick materials are essential for structural robustness and excellent radiation shielding. However, interference due to the thickness of panels restricts the folding mechanism, and avoiding the interference makes the pattern and folding sequence complicated. In this study, we propose a Recessed Pyramid Origami (RPO) module which can be folded into a pyramidal shape with a recessed center from a single flat plane. Although it has an open-loop pattern with a separation in a partial sector, it can achieve a simple one degree-of-freedom (DOF) folding motion by additional internal patterning. Its final shape is defined by panel-to-panel contact, eliminating the need for extra end-stoppers. Moreover, the RPO is rigid-foldable, enabling the use of thicker panels, and it can be designed in various shapes according to design parameters. The RPO also can create various 3D structures including approximated dome, prism, arch, corrugated panel, tube, and polyhedron by tessellating. It is anticipated that a wide range of foldable structures can be designed by utilization of the proposed RPO and its derivatives.