Scientists have developed what social media users have dubbed the ‘magnetic turd’ and they hope the medical field will one day employ to retrieve foreign objects from inside the body.
The Chinese researchers responsible for the slimy creation say the brownish, slug-shaped substance, immediately compared to the 1997 sci-fi film Flubber, can reportedly make ‘C’ and ‘O’ shapes and is electroconductive.
Calling it a magnetic slime robot, co-creator Professor Li Zhang, working out of The Chinese University of Hong Kong, described the substance in the journal, Advanced Functional Materials.
Zhang stressed that his work was indeed real and grounded in reality, despite the reaction in social media and the rather unfortunate publishing date of 1 April.
While the slime does not have autonomy and needs to be controlled by magnets, the team’s main objective was to deploy the substance like a robot, said Zhang.
The magnetic turd is made-up of polyvinyl alcohol, borax (a household cleaning agent) and neodymium magnet particles, which give it a unique set of properties that Zhang says he is still trying to fully understand.
Robotic slime has visco-elastic properties, sometimes behaving like a liquid and sometimes a solid, according to the research paper. Materials that possess this rare characteristic are called dilatant non-Newtonian fluids and are defined by their viscosity reaction when interacting with varying amounts of force.
Zhang said that the substance could be imitated by mixing corn starch and water to the correct consistency. When pressed gently, the mixture behaves like a liquid. When struck with enough force, the liquid stiffens, acting more like a solid material.
Other dilatant non-Newtonian fluids include silly putty and quicksand. Interestingly enough, tomato sauce is a pseudoplastic non-Newtonian fluid and behaves inversely to dilatants, losing viscosity with increased forces. This explains why shaking the bottle can lead to a disastrous mess if one isn’t too careful!
The slime’s malleability allows it to navigate 1.5mm wide passages, making the substance an ideal candidate for non-invasive surgeries such as retrieving accidentally swallowed Lego bricks and targeted drug delivery, according to the team.
There is still work to be done though. Zhang said the slime’s neodymium charge makes it too toxic to be introduced to the human body for an extended period. The Chinese-based scientists discovered some success coating the substance in a protective silica coating but found the toxicity was only partially contained.
https://interestingengineering.com/slimy-turd-like-magnetic-robot
