Harvard scientists have developed a new type of liquid

Harvard scientists have developed a metafluid that can adapt to the shape of a container. It has unique properties: its viscosity and transparency change depending on the form that its components take.

Info Apr 15, 2024 0 177 Add to Reading List

Harvard scientists have developed a new type of liquid, called a metafluid, whose properties can be programmed.

It consists of hundreds of thousands of microscopic elastic spheres (50 to 500 microns in size) floating in oil. The shape of these spheres changes depending on the pressure of the surrounding fluid. When the pressure increases, they deform and take on a crescent shape, and when the pressure decreases, they return to their original spherical shape.

“Unlike solid metamaterials, metafluids have the unique ability to flow and conform to the shape of their container.”
Katya Bertoldi, professor of applied mechanics at Harvard

Important characteristics of a metafluid, such as viscosity and opacity, are determined by the shape of its constituent spheres. They can be finely tuned by adjusting the number and size of these spheres, as well as their thickness.

To demonstrate the metafluid's capabilities, the team filled a hydraulic robotic gripper with it. This allowed the gripper to automatically adapt to objects of different shapes, such as a blueberry, glass or egg, without the need for additional sensors or programming.

The team also discovered that the metafluid can become more transparent when its constituents are compressed, whereas in a spherical state it becomes opaque. The compressed shape acts as a lens to focus the light, while the spherical shape diffuses the light.