Shape-changing metamaterial developed

Scientists have developed a new shape-changing metamaterial using Kirigami - the ancient Japanese art of cutting and folding paper to obtain 3D shapes.
Metamaterials are a class of material engineered to produce properties that do not occur naturally. Currently metamaterials are used to make artificial electromagnetic and vibration absorbers and high-performance sensors.
Kirigami can be applied to transform two-dimensional sheet materials into complex three-dimensional shapes with a broader choice of geometries than 'classical' origami.
The type of mechanical metamaterials using the Kirigami technique, developed by Robin Neville, PhD student at University of Bristol in the UK, changes shape seamlessly, exhibits large variations in mechanical performance with small geometry changes, and can be adapted to modify its configuration by using mainstream actuation mechanisms.

The Kirigami metamaterial can also be produced using off-the-shelf thermoplastic or thermoset composite materials, and different sensing and electronics systems can be embedded to obtain a fully integrated smart shape-changing structure.
"Mechanical metamaterials exhibit unusual properties through the shape and deformation of their engineered subunits," said Fabrizio Scarpa, Professor at Bristol's Department of Aerospace Engineering.

"Our research presents a new investigation of the kinematics of a family of cellular metamaterials based on Kirigami design principles.
"This technique allows us to create cellular structures with engineered cuts and folds that produce large shape and volume changes, and with extremely directional, tuneable mechanical properties," said Scarpa.

"By combining analytical models and numerical simulations we have demonstrated how these Kirigami cellular metamaterials can change their deformation characteristics," Neville added.
"We have also shown the potential of using these classes of mechanical metamaterials for shape change applications like morphing structures," he said.
In the future, this Kirigami metamaterial could be used in robotics, morphing structures for airframe and space applications, microwave and smart antennas.
The research was published in the journal Scientific Reports.