Clever "Active Matter" Could Give Future Robots Soft, Flexible, Shape-Shifting Capabilities

Two physicists and a chemist, from the Universities of Bath and Birmingham respectively, have come up with a new method for creating soft robots capable of shifting their shapes based on programming — using "active matter."

"Active matter makes us look at the familiar rules of nature – rules like the fact that surface tension has to be positive – in a new light," explains first author Jack Binysh, PhD, of the team's work. "Seeing what happens if we break these rules, and how we can harness the results, is an exciting place to be doing research."

"This study is an important proof of concept," adds corresponding author Anton Souslov, PhD, "and has many useful implications. For instance, future technology could produce soft robots that are far squishier and better at picking up and manipulating delicate materials."

Proven through theory and microscopic simulations, the team's work describes a 3D soft solid with a stressed surface. The fight between the stresses allows for "snap-through transitions," morphing the material into new shapes on-demand.

"These phenomena offer robust principles for programming shape change and functionality into active solids," the team explains, "from robotic metamaterials down to shape-shifting nanoparticles."

The work, the team proposes, could lead to soft machines with flexible arms driven by surface-embedded robotics, or drug delivery capsules with tailored sizes and shapes.

The next phase of the project: Putting the theory to the test with specific soft-robotic designs, as well as examining the collective behavior of many active solids packed into a small space.

The team's work has been published under open-access terms in the journal Science Advances.