Incredible Video Shows Flubber-Like 'Magnetic Slime' That Can Grasp Objects

Researchers have created incredible "magnetic slime" robots that have been compared to the eponymous substance from 1997 sci-fi comedy "Flubber."

The dark, magnetic slime is capable of navigating narrow spaces and grasping solid objects, according to the team of researchers who developed it.

The researchers have described the magnetic slime, which has a custard-like consistency, in a study published in the journal Advanced Functional Materials. A video of the "magnetic slime" can be seen here.

The authors wrote in the study that magnetic, miniature, soft-bodied robots allow "non-invasive access to restricted spaces" and could have potential medical applications, providing "ideal solutions" for minimally invasive surgery and targeted drug delivery.

However, the researchers said existing elastomer-based and fluid-based, magnetic, soft robots have their limitations. Elastomers are rubbery materials composed of long, chainlike molecules known as polymers.

Owing to their limited deformability, elastomer-based soft robots cannot navigate through highly restricted environments, although they can manipulate objects. In contrast, fluid-based soft robots, while more capable of deforming themselves and navigating tight spaces, are also limited by the unstable shape of the fluid itself.

A magnetic slime robot
Screenshot taken from a video of a “magnetic slime” robot that can navigate tight spaces and grasp objects. Dr. Mengmeng Sun/The Chinese University of Hong Kong

To try and address this problem, the researchers created a magnetic slime robot combining the properties of both elastomer-based and fluid-based soft robots.

"The robots can negotiate through narrow channels with a diameter of 1.5 [millimeter; a little over 1/32 inch] and maneuver on multiple substrates in complex environments," the authors wrote in the study.

They said the slime robot has several capabilities, including grasping solid objects, swallowing and transporting harmful things, and even fixing broken electrical circuits.

"This study proposes the design of novel soft-bodied robots and enhances their future applications in biomedical, electronic, and other fields," the authors wrote.

The slime is made from a polymer called polyvinyl alcohol, mixed with a powdery, white substance known as borax and magnetic particles made from the rare Earth metal neodymium.

Li Zhang, a co-creator of the slime and one of the authors of the study from the Chinese University of Hong Kong, told The Guardian that the slime has "visco-elastic properties," meaning that sometimes it behaves like a solid, and other times like a liquid. In fact, the viscosity of the substance changes under force.

"When you touch it very quickly it behaves like a solid. When you touch it gently and slowly it behaves like a liquid," Zhang said.

The magnetic particles in the slime can be manipulated using external magnets to make the robot move, rotate or form "C" and "O" shapes.

In the future, such a magnetic robot could be used for medical applications, for example, to remove objects that have been accidentally swallowed.

"We are thinking that one potential application of the slime robot is for digestive system-related diseases or issues," Zhang told Newsweek. "Or perhaps, it can be applied for the quick repairing or connection of electrodes in hard-to-reach locations."

"The ultimate goal is to deploy it like a robot," Zhang told The Guardian, noting that, for now, the slime lacks autonomy. "We still consider it as fundamental research—trying to understand its material properties."

Currently, the magnetic particles in the slime are toxic so the researchers covered the robots in a layer of silica to create a hypothetically protective layer.

"The safety [would] also strongly depend on how long you would keep them inside of your body," Zhang said.

Several users on social media compared the magnetic slime to the imaginary substance portrayed in the film Flubber. "You call it 'a robot made of magnetic slime' I call it 'Flubber,'" said one Twitter user.

Update 04/04/22, 8:14 a.m. ET: This article was updated to include comments from Li Zhang and to add a new image.

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