From the dramatic snap of a Venus flytrap to the quick jump of a robot, snap-through instabilities— and the sudden shape changes they cause — are everywhere.
From the dramatic snap of a Venus flytrap to the quick jump of a robot, snap-through instabilities— and the sudden shape changes they cause — are everywhere. Yet harnessing them has remained a challenge. Now, Dr Mingchao Liu from the Department of Mechanical Engineering at the University of Birmingham, working with international partners, has found new ways to precisely control how these snapping motions unfold, opening the door to smarter, more reliable designs in technology and engineering.
In a breakthrough published in Science Advances, the team showed how tiny magnetic patterns embedded in soft materials can be used to guide the snapping process. By strategically designing where and how magnetism is introduced, researchers were able to create structures that snap symmetrically and predictably — a major advance over traditional systems that tend to buckle unpredictably to one side.
Another recently-published study in Physical Review Letters revealed that the speed of snapping also plays a critical role. Combining a series of experiments and a toy model, researchers discovered that moving slowly allows asymmetries to grow, while faster motions can suppress them, leading to perfectly even snaps. This insight points to a universal principle that could be used to control symmetry in a wide range of systems beyond snapping structures.
On these discoveries, Dr Mingchao Liu said:
These findings give us a powerful new toolkit. By combining material design and dynamic control, we can guide structures to change shape exactly as we want— whether it's a soft robot gripping gently or a deployable satellite unfolding in space.
Different snapping modes of a bistable beam made by the hard ferromagnetic soft elastomer.
The potential applications are vast - from robotics and aerospace to medical devices and smart materials - anywhere reliable and precise motion is critical.
This new research promises not only to make future technologies more efficient but also more robust and adaptable, changing the way we think about the design of morphing structures.
Assistant Professor
Staff profile for Dr Mingchao Liu, University of Birmingham
