Inspired by "Traditional Patterns"... SeoulTech Develops 4D-Printed Metamaterials and Soft Robots

Realizing 4D-Printing-Based Robot Actuation Mechanisms
"Collaborative Research Proposals from Researchers Overseas"

Seoul National University of Science and Technology said on November 11 that a research team led by Professor Park Geun of the Intelligent Robotics major in the Department of Mechanical System Design Engineering had developed 4D-printed metamaterials inspired by traditional Korean patterns and successfully applied them to various soft-robot mechanisms.

Professor Geun Park of Seoul National University of Science and Technology (left), who developed 4D-printing metamaterials and soft robot mechanisms, and researcher Euihyeon Kim. Seoul National University of Science and Technology

The team developed a kirigami metamaterial structure based on dissimilar materials, using the geometric patterns of traditional dancheong designs. Kirigami is an extension of origami that allows cuts to be made along lines in a flat material, in addition to folding, to create patterns and structures. It can be seen in everyday items such as pop-up books and three-dimensional cards.

In particular, the team established a design method that enables precise control of bistable deformation and thermally induced shape recovery by optimizing structural design parameters. By combining multiple structures, the method can also program multistable deformation and sequential 4D shape changes. The team further demonstrated the potential of the developed 4D kirigami metamaterial for use in a range of soft-robot mechanisms by fabricating, with a material-extrusion (MEX) 3D printer using PLA and TPU, a multimodal bridging mechanism, a soft gripper capable of both inward and outward grasping, and a bio-inspired robot that changes size underwater to collect waste.

Examples of applications of multistable 4D deformation technology based on heterogeneous kirigami metastructures developed by a SeoulTech research team, and soft robotic mechanisms. Seoul National University of Science and Technology

Researcher Kim Euihyun, who participated as the first author, said, "Kirigami is a structure that originated in Japan's paper-cutting culture. Recently, it has drawn attention as a metamaterial that can achieve auxetic deformation, characterized by a negative Poisson's ratio, and bistability. This study is significant because it developed a new kirigami structure inspired by traditional Korean dancheong patterns and achieved multistable deformation and thermally induced 4D shape recovery by combining active and passive materials."

Professor Park, who participated as the corresponding author, said, "As a Korean researcher, I feel great pride that research inspired by traditional Korean dancheong patterns has been featured on the cover of a world-renowned academic journal. We have filed two patent applications related to this technology. As researchers from around the world have proposed collaborative research, we plan to expand our work to various metamaterials and soft-robot mechanisms."

The study was published in the internationally renowned journal Advanced Science and, in recognition of its excellence, was selected as the front-cover article for Volume 13, Issue 62, published on November 9. Kim Euihyun, a master's student in the Department of Mechanical Design and Robotics at Seoul National University of Science and Technology, participated as the first author. Researcher Kim Minseong of the same department and Professor Yoon Hyunsik of the Department of Chemical and Biological Engineering participated as co-authors.

This content was produced with the assistance of AI translation services.