Retractable Structures

This work is patent protected. Please consult Z. You if you want to use it.

The latest development in a series of new structures that I have developed is a new general concept for foldable roof structures. These retractable frames are based on special, two-dimensional tiling of parallelograms. It is possible to design structures of any shape, e.g. circular or elliptical, consisting of multi-angulated rods connected by "scissor" hinges at the kink positions. Although these structures contain many hinges, they retain a single internal degree of mobility. Their motion is similar to the operation of the diaphragm in a camera lens. In the fully-open configuration all rods overlap along the outer edge.

These two-dimensional solutions can be extended to curved structures, by projecting any two-dimensional solution onto a surface with the required shape. Thus, each rod becomes curved out of plane; however, all connectors between rods are perpendicular to the plane of projection. With this technique, double layer structures can be built, and bracing elements can be added between the upper and lower cords, to increase the stiffness of the structure.

This page is created by Zhong You, who is a university lecturer in the Department of Engineering Science of Oxford University. This is a link to his current address. You may e-mail zhong.you@eng.ox.ac.uk for further infomation.

Zhong was an EPSRC advanced fellow based at Cambridge University before moving to Oxford.