No matter how its done, with whatever level of fakery, magnetic levitation just looks cool.  We don’t know about you, but merely walking past the tackiest gadget shop, the displays of levitating and rotating objects always catches our eye. Superconductors aside, these devices are pretty much all operating in the same way; an object with a permanent rare-earth magnet is held in a stable position between a pair of electromagnets one above and one below, with some control electronics to adjust the field strength and close the loop.

But, there may be another way, albeit a rather special case, where a magnet can not only be levitated, but locked in place using a rotating magnetic field. The video shows a demonstration of how the mass of a magnet can be used to phase lock it against a rotating field. In essence, the magnet will want to rotate to align with the rotating magnetic field, but its mass will mean there is a time delay for the force to act and rotation to occur, which will lag the rotating magnetic field, and if it is phased just so, the rotation will be cancelled and the magnet will be locked in a stable position. Essentially the inertia of the magnet can be leveraged to counteract magnet’s tendency to rapidly rotate to find a stable position in the field.

Whilst the idea is not new, Turkish experimenter [Hamdi Ucar] has been working on this subject for some time (checkout his YouTube channel for a LOT of content on it), even going as far as to publish a very detailed academic paper on the subject. With our explanation here we’re trying to simplify the subject for the sake of brevity, but since the paper has a lot of gory details for the physicists among you, if you can handle the maths, you can come to your own conclusions.

Thanks [keith] for the tip!

[Stoppi] always has exciting projects and, as you can see in the video below, the latest one is a very simple magnetic levitator design. The design is classic and simple: a 5 V regulator IC, a Hall effect sensor, a 741 op amp, and a MOSFET to turn the electromagnet on and off.

Sure, there are a few passive components and a diode, too, but nothing exotic. The sensor normally presents 2.5 V of output. The voltage rises or drops depending on the polarity of the magnetic field. The stronger the field, the more the voltage changes away from the 2.5 V center.

The op amp acts as a comparator with a potentiometer setting the trip point. As the ball moves up towards the coil, the voltage increases, triggering the comparator, which turns off the FET. With no current through the coil, there’s no more electromagnet, and the ball starts to fall.

Of course, as the ball falls, the voltage from the sensor also drops, and this eventually turns on the electromagnet. The ball eventually reaches a relatively stable position.

This is one of those cases where a simple analog circuit might work better than a digital one. Or make it hard on yourself and use an FPGA.

One of the problems with laser cutting projects is that while they look good, they often look like they were laser cut. [Timber Rough] has a wooden desk lamp that not only looks good but has one of the most unusual dimming features we’ve seen.

One thing that stands out is the lamp is made of different kinds of wood, and that helps. But the dimmer is a magnet and Hall effect sensor that levitates. It is hard to explain, but a quick look at the video below will clarify it.

The lamp software borrows from another project so it has animated effects and WiFi control with little effort. A custom “usermod” handles the custom levitating dimmer.

If you decide to duplicate the lamp, the instructions are very detailed, and any questions you may have will probably succumb to the video. The project is a fusion of woodworking, laser skills, and electronics. Overall, it is a beautiful and well-documented project.

Of course, you could go the simple route. If you want to add more features, there’s plenty of brainpower in the lamp.

Magnetic levitation has not quite revolutionized the world of transit the way some of us might have hoped. It has, however, proven useful to [mrdiytechmagic], who has put the technology to grand use in making his levitating snail lamp.

The build is actually relatively complicated compared to some levitating toys you might have seen before. It uses a number of coils to produce a magnetic field to levitate the 3D printed plastic snail which contains the lighting element itself.

The actively controlled levitation base uses a magnetic sensor to detect the changing field as the snail moves above it. It then varies the current going to the various coils to keep the snail balanced and in place. Power is transmitted with a further larger coil, much as in a wireless phone charger. This is picked up by a circuit in the snail, and used to power the LEDs inside.

It might not have been our first choice, but having seen it in action, we can’t deny a levitating 3D printed snail is pretty impressive. If you’d prefer something slightly more befitting such a high-tech looking presentation, perhaps a hovering SpaceX Starship would be more your speed.