There is a simple way to levitate magnets – and physicists are beginning to understand how it works. The technique could have applications for robotics in the future.
In 2021, – then at Göksal Aeronautics in Turkey – posted a YouTube video showing two magnetic spheres levitating on either side of a rapidly spinning bar magnet that was positioned with its north-south poles oriented vertically. Ucar also published a paper on the phenomenon, which attracted the attention of at the Technical University of Denmark.
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With a colleague, Bjørk decided to replicate Ucar’s levitation technique. “We sat down for half an hour and tried. I was like, it’s completely out of the question, it simply shouldn’t work. And then it just worked. We were completely baffled by this,” he says.
Now, Bjørk and several other colleagues, all at the Technical University of Denmark, think they understand what’s going on.
They started with Ucar’s setup, where a “floater” magnet levitates when placed on top of another magnet that is spinning hundreds of times every second. Then they tested a range of spinning frequencies and floater sizes while filming the magnets and measuring their magnetic fields. The researchers also developed a computer simulation of the experiment.
who worked on the project, says the rotation is key to the process. He says many people are familiar with the way two magnets repel one another when both north poles (or both south poles) are close together. But usually, one of the magnets will simply flip over, meaning that a north and south pole are close together – at which point they stick to each other.
Durhuus says the rotation counters this magnetic “flipping” and keeps the floater levitating. He compares it to the way a spinning top counters the downward pull of gravity and spins for longer than we might expect.
Ucar’s experiments show the effect can persist , rather than vertically like a spinning top. He disagrees with some details of the team’s numerical and theoretical models, but he says that their independent validation of this surprising effect is important.
“I don’t think we will be able to make any [magnetically levitating] trains with this anytime soon, but it will be interesting to see where it can be useful because it does not require very fancy equipment,” says who was also part of the team.
at No-Touch Robotics in Switzerland says that magnets are already used for suspension and transport of objects in some industries. He says using the rotation scheme could be a simpler alternative to systems that require their magnets to be constantly readjusted.
Physical Review Applied
