Introduction: A New Shape-Morphing Milestone
Researchers at North Carolina State University have unveiled a groundbreaking shape-morphing structure inspired by a traditional Chinese lantern. Published in Nature Materials, the design demonstrates how a single thin polymer sheet can transform into multiple stable three-dimensional shapes when triggered. By combining geometry, elastic energy storage, and magnetism, the team has taken a major step toward adaptive machines that can reconfigure themselves on demand for diverse tasks in robotics, filtration, and responsive materials.
The Lantern Design: From Flat Sheet to Hollow Sphere
The core idea begins with a diamond-shaped parallelogram of polymer. Evenly spaced slits carve the sheet into narrow ribbon patterns, linked by solid strips at the top and bottom. When the ends are joined, the sheet naturally folds into a hollow, spherical form reminiscent of a paper lantern. According to Jie Yin, a Professor of Mechanical and Aerospace Engineering at NC State, this lantern-like shape is bistable: it remains stable in its lantern form, but compressing it can snap it into a second stable shape that resembles a spinning top. When released, the structure rapidly returns to its original form, unleashing stored elastic energy in a process the researchers call snapping morphogenesis.
By combining twisting and folding, the team produced a family of configurations, some with as many as four stable states. This multistability is essential for reliable, repeatable actuation in real-world environments.
Remote Control: Magnetism Unlocks Motion
A thin magnetic film applied to the lantern’s lower strip enables noncontact actuation. An external magnetic field can induce twisting or compression, allowing precise manipulation without direct mechanical input. Demonstrations showcased the lanterns acting as gentle grippers that can catch and release live fish without harm, as well as fluid-control valves that open and close underwater. Other demonstrations captured the rapid reopening of a collapsed tube, all powered by the quick release of stored elastic energy.
Video footage of the devices in operation presents motion that feels almost lifelike. The lanterns snap and twist with a rhythm that resembles breathing, rather than a purely mechanical motion, highlighting the potential for smooth, adaptable interactions in soft robotics.
Programming Shape and Energy: A Predictive Model
To control the transformations, the researchers developed a mathematical model linking lantern geometry to stored elastic energy. This model enables designers to tailor a configuration’s stability and power output for a given task. Lead author Yaoye Hong of the University of Pennsylvania explains that the model makes it possible to program the exact shape, stability, and energy release characteristics needed for a desired action.
Geometry serves as the primary control knob in this system. By adjusting angles, folding patterns, and ribbon patterns, engineers can fine-tune how the structure stores energy and how rapidly it can convert that energy into motion.
Towards Shape-Morphing Machines: Implications for Robotics and Beyond
Each lantern unit is reprogrammable and remotely triggerable, suggesting a modular approach to building smart materials. According to Yin, these lanterns can be assembled into two- and three-dimensional architectures to underpin shape-morphing metamaterials and robotics. Potential applications include adaptive robots capable of crawling, swimming, or grasping with magnetically actuated limbs, as well as sensors and filtration systems that unfold to regulate flow or response to environmental conditions.
A New Generation of Smart Materials
Multistability is increasingly a central theme in smart materials research. By integrating physics and engineering principles, this lantern design demonstrates how a simple device can become a powerful platform for advancing adaptive technologies. Using a single polymer sheet, the NC State team shows how magnetism, geometry, and stored energy can work together to produce fast, repeatable motion. The research may lay the groundwork for an all-new generation of adaptive machines that respond to their surroundings with minimal energy input.
Conclusion: A Bright Path Forward for Adaptive Systems
The study, “Shape-Shifting ‘Chinese Lantern’ Structure Could Pave the Way for the Next Generation of Adaptive Machines,” marks a pivotal moment in shape-morphing materials research. By achieving controlled, multistable configurations powered by magnetism and nanoscale geometry, this work points toward practical, scalable solutions for soft robotics, smart membranes, and responsive devices. As researchers explore larger assemblies and real-world integrations, the lantern-inspired approach could redefine how machines sense, adapt to, and interact with their environments.
