Expandable structure: objects that transition from a compact state to an expanded state, from the backyard to Mars everywhere. However, it is sometimes a challenge to convert a two-dimensional form into a three-dimensional structure.

Now, researchers at Harvard University's John A. Paulson School of Engineering and Applied Sciences (SEAS) and Harvard Graduate School of Design have developed a deployable system that is light, compact, inexpensive, easy to manufacture, and most importantly The thing is, easy to deploy. By taking advantage of the mechanical instability in the curved beam, the system can transform objects into detailed and customizable 3D configurations of all sizes, from large furniture to small medical equipment.

By taking advantage of the mechanical instability of curved beams, researchers have developed a system that can transform objects into fine and customizable 3D configurations. Above, the researchers showed a lampshade that can be opened and closed with simple actions.

By taking advantage of the mechanical instability of curved beams, researchers have developed a system that can transform objects into fine and customizable 3D configurations. Above, the researchers showed a coffee table, which can be folded flat and popped out with a simple motion.

Most deployable structures caused by buckling, such as folding chairs, are activated by the compressive force generated by the linear displacement of the element. Saurabh Mhatre, a research assistant at GSD and the first author of the paper, said that our method is different. It is produced by rotational movement, which in turn causes buckling, which acts as a trigger for the 2D to 3D conversion.

An interdisciplinary research team of designers and engineers uses a combination of experiment and numerical analysis to understand the geometry of curved slender beams and what happens when these beams rotate and bend. By taking advantage of buckling, a phenomenon that is generally undesirable in design and engineering, researchers are able to design deployable structures with simple rotational motions.

To demonstrate the system, the team made a lampshade that can be rotated to allow more or less light to enter, and a coffee table that can be folded flat and popped out with a simple action.

This new platform can be extended to use a variety of different materials to achieve functional structures and equipment from millimeters to meters. The senior author of the study and Professor Katia Bertoldi of SEAS Applied Mechanics William and Ami Kuan Danoff said that these structures can be used as medical Equipment, optical equipment, such as camera focusing mechanism, deployable wheels and turbines, furniture or deployable shelters.

The research was recently published in Advanced Materials. It is co-authored by Elisa Boatti, David Melancon, Ahmad Zareei, Maxime Dupont and Martin Bechthold. It was partly supported by the National Science Foundation through the Harvard University Materials Research Science and Engineering Center with funding from DMR2011754 and DMR-1922321.