Biomimetic Deployable Canopy
- Giulia Fenci
- Neil G. R. Currie
- Laura Civetti
Drawing inspiration from the floral world, the design of a freestanding, biomimetically inspired, deployable canopy is proposed.
Nature inspires the structure in terms of mechanism and shape, allowing for the creation of a lightweight and efficient deployable awning. With the desire of creating a temporary and multifunctional space that could be used as a shelter from the rain or the beating sun, inspiration was found in the biological world, in particular among flowers.
Different species of flowers exist, each one with their own distinguishing characteristics, for example, Venus Flytraps that close around their victims through to flowers that create large attractive blooms such as Allium. After reviewing blooming topologies for numerous species, the blooming of the Morning Glory flower (Ipomea Violacea) presented an advantageous morphology for the creation of the deployable awning as it moves from a tight rod like bud to an open conical based flower.
The observation of fast motion videos showing the blooming of a Morning Glory flower allowed a more precise understanding of the governing movement to be established. Physical and digital models of the deployable structure with three distinct degrees of mechanical freedom were created using Grasshopper, Rhino and Autodesk ROBOT, reproducing the motion synthesized by the flower’s unfolding process.
The choice of four struts was based on research by Kobayashi, Daimaruya, and Fujita. While the structure could have been designed with a greater number of ribs to help reduce the working stresses, this would come at the cost of hindering the density of packing during the folded state. Furthermore, there need to be enough struts to ensure structural stability, but not too many that would make the structure too bulky in the packed state.
Three degrees of freedom were identified, each one controlled independently. The degrees of freedom are: the rotation of the lower level plate, its elevation along the central mast, and the extension of the higher level pistons.
Through careful control of each degree of freedom the geometry was frozen at specific deployment stages to create a time-stepped analysis based on pseudo-static principles, showing the structure at various stages of deployment. The freezing of the structure allowed a parametric investigation of the most suitable deployment sequence to minimise the deployment forces and associated quantities of steel refining the structure to a minimum, just as nature does.
The flower model can deploy in almost infinite ways, due to its degrees of freedom and how these control and refine the motion of the structure during deployment.
The transformable structure mimics nature’s beauty and elegance behaving just as the flower does, opening from compact to voluminous, but equally it has been made efficient through the application of optimisation techniques to engineer the most favourable deployment sequence to reduce the stresses and forces during deployment.