Why Build a Magnetic Levitation Device?

Wacko Sales Pitch

Want to amaze and impress your friends?

Can something be held in mid-air with nothing touching it?

Do flying saucers use electrogravitics?

How does a maglev vehicle work?

Need a super accurate force/weight measurement?

Want to measure small changes in gravity?

Who says gravity cannot be beaten?

Want to see a simple coil levitate a steel ball in a magnetic field?

As long as you're building a coilgun, and have: magnet wire, power supply, breadboard, voltmeter, resistors and capacitors, switches, hookup wire, and other miscellaneous parts, why not?!

Maglev for Science Fair

I started this project with my 2nd grade son for a science project. The science fair was on March 16th, 1999, at an elementary school in Washington state. This was a fair, not a competition, where the emphasis is on having fun. Most sane parents would not design a closed-loop feedback control system with a second-grader, but as it turned out we didn't enter the project in the fair after all. It didn't work quite well enough, and the coil would overheat after a few minutes.

The benefits of doing this project were many, but not where I expected. I somehow expected to relate some ideas about electronic design. In reality the benefits were probably of more lasting effect. I worked together with my 7-year old and we had a great time. This was a chance for him to cut boards with a saw, drill holes, handle a screwdriver, measure and mark with a square, cut wires, and plug in chips and resistors. We handled parts, learned their names and looked at their symbols in schematics.

Some other things we accomplished were:
- To play with a cool gadget that we made ourselves.
- To experiment with magnetism, and see and feel how it works.
- To be challenged by designing a closed-loop control system.
- To use what I learned from my first coilgun, and learn more that might help with my next one.
- To refresh my knowledge of op-amps and analog circuits.
- To use up part of a mile of 24ga magnet wire.
- To buy new tools, in this case a dual-tracking 30v 5a lab bench power supply bought cheap at an auction.
- To learn how IR emitters and phototransistors work.
- To help fill my garage with electromagnet toys.

Okay, enough yackity marketing material, let's get on with the technical details you really want.