Asymmetric Zipper-Coupled Tubes and Smooth Sheet Attachments in the Design of Deployable Space-Filling Mechanisms

Zipper-coupled tubes constructed from Miura-ori cells are a unique structure consisting of two tubes which, when coupled in a zipper fashion, resist compression in the normal direction. A wider application of zipper-coupled tubes, however, is precluded by their angular form and symmetry. We demonstrate the construction of asymmetric zipper-coupled tubes based on an asymmetric degree-four vertex, along with a smooth sheet attachment that is flat when the asymmetric zipper-coupled tubes are fully deployed. Furthermore, we provide a mathematical model of the motion of the resulting mechanism, thereby demonstrating the rigid-foldability of the entire mechanism.