Electronic Levitron...How the heck does this thing work?

[Pirate88179]

In my continued searching on the Levitron, I am reading more and more reviews where it breaks down after only a few days.  There are quite a few complaints of this nature.  They also make a levitating globe which is a little smaller device using the same approach, and I also read at least 3 reviews where that one quit working after just a few days.  If I paid $100 or so for this and it broke after a few days, I would be sending it back.

I have not yet found where anyone has taken the base apart and video taped it or took photos.

I will continue to search.

Bill

[pavqw]

It is not that hard to built one.
You will need hall sensor(s), coils A, B and some neodymium magnets.
There must be exact proportion between all these stuff to get the best results.
With microprocessor you can do it even more sophisticated.

It would be nice if permanent magnet can be replaced with electromagnet to change levitation height. With this you can make even cooler levitated platforms.

But if you want to really levitate things, I can see much higher potential in ion thrusters.

[Pirate88179]

I am now thinking that maybe...possibly, I can convert one of my one magnet, no bearing Bedini motors (Ala Johnnydavro) into one of these levitrons?  It has the electromagnetic coil placed vertically, and the circuit to pulse it....I think we need to find out a way to swap polarities on the electro mag and also add some stabilization perma mags around the base.

It might be easier to start from scratch but this idea hit me today and I am still thinking about it.

Bill

One of my videos of the Johhnydavro replication: https://www.youtube.com/watch?v=8RsFMyZbj1I&list=UU0bTBCRogMzrYTQT3pbhxwg

[TinselKoala]

Bill,  the way to do it is to use an H-bridge, or equivalently an op-amp circuit, that will switch output polarity in response to a sensor input. Two example "sketches" are below. Just substitute the coil for the motor M in the circuits. These are bare-bones sketches of course, the real circuit will have some more complexity depending on your sensors, power supplies, etc.
You'd need relatively highpower op-amps that can source and sink sufficient current on the outputs to the coil. Like maybe OPA549 from TI.

[TinselKoala]

Here's a more complete and simpler solution but requires a bipolar power supply, +/- voltage wrt a "zero" ground level. The 741 op amp is as common as sand and about as cheap.

If Vin to pin3 of the 741 is above the ground level the motor or coil runs one way, if the Vin is below the ground level the motor or coil runs the other way. The Vin comes from a potentiometer voltage divider (ends to Vcc+ and Vcc-, wiper to Pin3) or other sensor system.