Dragonfly wings-inspired deployable structures

Maintaining the overall shape of a flat structure while increasing its surface area is a nontrivial challenge when designing soft structures. When the wing of an emerging dragonfly deploys in a couple of minutes, the expansion is guided by a network of veins, in which hemolymph is injected and subsequently solidifies to generate rigidity. During the deployment stage, the looping patterns of the edge of the wings are characteristic of differential growth. Inspired by this insect, we build a model experiment of the inflatable deployable structure composed of a tubular network of the veins. We first characterize the response of a unique looping tubular structure under pressure. We then characterize the in-plane expansion of the structure and study its correlation to the network geometry and the pressure applied in the system. A systematic variation of the geometric and elastic parameters allows us to search for an optimal design and operational conditions for maximal extension, while minimizing the input pressure.