Abstract

Many aerospace arrays have large flat profiles composed of regular polygonal panels. They need to be packaged into small volumes for launch, and subsequently deployed to seamless flat surfaces once in orbit. Examples of such structures include solar arrays and reflectarray antennas, which are made from rigid thick panels. It is always very challenging to package such arrays compactly without any voids, especially when they are composed of panels with uniform thickness and are designed to have bi-directional deployment with a small number of degrees of freedom. In this talk, I shall demonstrate a kirigami based approach that enables compact folding of such arrays without any voids.

Origami and kirigami have great advantages in folding large thin sheets into compact volumes. However, when thick panels are involved, origami based approaches often lead to large gaps along the hinges or uneven surfaces in deployed states. In the newly proposed approach, a thick-panel deployable kirigami element is first introduced using the Hamitonian circuit in which eight panels with shapes of isosceles triangles and parallelograms are connected together by revolute joints. It is effectively an eight-link closed kinematic chain, named as an 8R element, that can be folded compactly without any voids. After that, four such elements are coupled together to form a deployable structure with a single degree-of-freedom. More 8R elements can be added to tessellate a plane. Although slits are introduced in the tessellation to accommodate thick panels during the folding process, they are completely closed in the fully deployed states. Therefore, a completely flat array made from thick panels with uniform thickness is obtained that retains the compact folding property of its constituent elements.