In the field of metamaterials, many have taken inspiration from the Japanese art of folding, origami. It is a great way to strengthen the material, but can be labour intensive. Taking another approach, researchers at Harvard John A. Paulson School of Engineering and Applied Sciences have drawn inspiration from another Japanese paper craft, that of kirigami, to change the structure and function of materials quickly and easily.

Instead of folding, kirigami relies on cuts to change the structure and function of materials. By doing so, a thin, perforated, flat sheet can be transformed into a foldable 3D structure by simply stretching the cut material.

The researchers found that when applying sufficiently large amount of stretching, buckling is triggered. This results in the formation of a 3D structure comprising a well-organised pattern.

If the material is stretched more, the temporary deformations become permanent folds. The pop-up pattern and resulting mechanical properties of the material can be controlled by varying the orientation of the cuts.

Photos: Ahmad Rafsanjani/Harvard SEAS