Researchers from the Harvard John A. Paulson School of Engineering and Applied Sciences have created a groundbreaking programmable metafluid that has the ability to change its springiness, optical properties, viscosity, and transition between a Newtonian and non-Newtonian fluid. The metafluid utilizes a suspension of small, elastomer spheres that buckle under pressure, altering the characteristics of the fluid. This innovative fluid could have a wide range of applications, from hydraulic actuators and robot programming to shock absorbers and optical devices.
Unlike traditional solid metamaterials, the metafluid flows and adapts to the shape of its container, providing a unique advantage. The team aimed to create a metafluid that not only possesses these adaptable characteristics but also allows for programmable viscosity, compressibility, and optical properties. By employing a scalable fabrication technique, the researchers produced spherical capsules filled with air and suspended them in silicon oil. When the pressure inside the liquid increases, the capsules collapse, changing the liquid’s properties, including viscosity and opacity, which can be adjusted by varying the number, thickness, and size of the capsules.
The programmability of the metafluid was demonstrated by loading it into a hydraulic robotic gripper capable of picking up a glass bottle, an egg, and a blueberry without crushing them. Unlike traditional hydraulic systems, the metafluid allowed the gripper to adjust its force without the need for external sensing or control. The metafluid also showcased its optical properties, transitioning from opaque to transparent when the capsules collapsed, forming micro lenses. Additionally, the metafluid switches between a Newtonian and non-Newtonian fluid, responding to temperature changes and shear forces.
The researchers plan to delve into the acoustic and thermodynamic properties of the metafluid to further explore its capabilities. With its scalability and ease of production, the potential applications for metafluids are vast. Harvard’s Office of Technology Development holds the intellectual property associated with this research and is considering commercialization opportunities. The study, supported by the NSF, was published in Nature and co-authored by a team of researchers from Harvard University, highlighting the collaborative effort behind the development of this groundbreaking metafluid.
