robhogg.com » Float something!

Float something!

stellanova_blue_and_silver_8_inch_magnetically_levitating.jpg

A friend of mine has a Stellanova floating globe that I got to play with. After fooling around with it a bit it became clear that they are using a little feedback system to control the electromagnetic force – some variant of a PID controller. Maybe they use some hall effect sensor for input to control their electromagnet?

It was pretty cool, I could grab the globe and pull it down a little bit and feel the pull get stronger instantly, and then go the other way and feel it let off a bit. The control is very tightly done with a small but very strong magnet (probably rare-earth) that is embedded at the top of the globe.

So basically you could pull the magnet out of the globe (or find an equivalent magnet) and embed it at the top of any object that weighs about the same as the globe, and you’d have yourself a floating [insert object name]!

Ideas anyone?