Kirigami-Inspired Magnetic Device Promises Precise Manipulation for Fragile Objects

Innovative metasheet design combines magnetic fields and kirigami to remotely move delicate objects in challenging environments.

Researchers at North Carolina State University (NC State) have developed a new device that could revolutionise how delicate materials are handled in confined spaces. This technology, which utilises magnetic fields and kirigami-inspired design, offers a novel way to move objects without the need for direct contact, making it particularly useful for fragile items, liquids, or any other materials that might be damaged by conventional robotic grippers.

Kirigami, the Japanese art of cutting paper to create intricate designs, plays a crucial role here. The principles of kirigami allow a material to maintain flexibility while retaining enough structural stiffness to perform mechanical tasks. In the new device, researchers applied these principles to create a flexible ‘metasheet’ capable of adaptive dynamic movement.

The Science Behind the Metasheet

The metasheet consists of an elastic polymer embedded with magnetic microparticles, which has been intricately cut into a specific pattern based on kirigami design principles. These cuts amplify the deformation of the sheet, enabling complex shapes and wave-like motions, without sacrificing the mechanical strength of the metasheet. By controlling a magnetic field underneath this metasheet, researchers can make different sections bulge or sink, effectively turning the surface into a programmable manipulator.

“Controlling the surface movement of the metasheet makes it possible to move many types of objects resting on the surface – whether they’re drops of liquid or a flat piece of glass,” explains Joe Tracy, co-corresponding author and professor of materials science and engineering at NC State. “The design of cuts on the metasheet are an example of kirigami, or paper-cutting.”

The magnetic control also enables the metasheet to move like a wave, depending on the direction and intensity of the applied magnetic field. “You can actually cause the surface of the metasheet to move like a wave by controlling the direction of the magnetic field,” says Jie Yin, co-corresponding author and associate professor of mechanical and aerospace engineering at NC State. “And adjusting the strength of the magnetic field determines how much the wave rises or falls.”

This ability to precisely adjust the movement of the metasheet has a significant implication for soft robotics, allowing researchers to manipulate objects that would typically be too fragile for robotic grippers or located in confined spaces that traditional robotics might struggle to access.

Applications and Future Prospects

The versatility of the metasheet makes it an exciting development in the field of material manipulation. As highlighted by Yin, the team aimed to address two key challenges: moving objects that are fragile or cannot be grasped easily, and developing a system capable of remotely controlling non-magnetic objects. The metasheet technology addresses both challenges by providing a non-invasive way to manipulate various types of materials, including gels, liquids, and delicate solid objects.

The research team is already considering how to extend their work. Yinding Chi, the study’s first author and now a postdoctoral researcher at the University of Pennsylvania, noted the potential for scaling the metasheets down to manipulate smaller objects or volumes of liquid with precision. In addition, Chi mentioned potential applications in haptic technologies, which could span from gaming devices to accessibility solutions. This adaptability and responsiveness are thanks to the metasheet’s rapid response time, as fast as two milliseconds.

“There’s been rather little work done on how magnetic actuation can be used in conjunction with kirigami, and what we’ve done here suggests that there’s a tremendous amount of potential for combining these approaches in fields from soft robotics to manufacturing applications,” says Tracy.

The paper detailing these findings, titled “Magnetic kirigami dome metasheet with high deformability and stiffness for adaptive dynamic shape-shifting and multimodal manipulation,” was be published in Science Advances.