Intro: Serenity Motor or Magnetic Levitating Armature Motor (Bedini Motor?)
Seems there are several version of this motor out there. It uses parts of the Levitron, floating pencil trick, the Mendocino motor, Bidini Motor, Robert Adams electromagnetic pulse motor, Lidmotor,... So I decided to just call mine the Serenity Motor in honor or Kaylee the verse's best Firefly class mechanic. Hey, it's all just geekdom.
This motor uses a levitating axle or armature constructed with a dowl (fishing pole section in my case), 12 magnets, an electromagnetic coil and driving circuit to pulse the armature and assorted wooden mounting stuff.
I used the electromagnet circuit described here: http://www.trainelectronics.com/Pendulum/article.h...
and that is a great little project in itself and is best told by the author how to construct so I won't show that here.
This is a fun little project that is simply amazing in it's simplicity of construction, it's mesmerizing function, and it's ability to stimulate the imagination.
Hope you like it.
Update: I tried using an Arduino rather than the two transistor circuit kicker but the Arduino doesn't supply enough current to the coil though it senses the approach of a magnet just fine. Then I tried a motor shield with the Arduino and with an external power supply it provides plenty of current to the coil but the Adafruit shield has no current sensing built in and it would involve using some more pins and circuitry and I felt not worth the trouble. Also it requires two power supplies, one for the coil and one for the Arduino. So this simple circuit is the best, most efficient solution. I do plan to replace the 1meg resistor with a potentiometer to control the timing of the magnetic kick or push.
Update Feb 24: added three more magnets to the rotor, replaced the drill bit pivot point with a smaller tip of a multi-tip screwdriver and the rotor is much more balanced and runs smoother and faster.
Step 1: Framework
The platform I used to hold the magnets is just a bamboo cutting board. The holes are not necessary - I swiped this board from a previous project.
I used a couple pieces of scrap wood to support the support magnets. I used Neodymium magnets with holes in them as they are easy to mount to the board with a screw. The two magnets on the left have their North polarity facing left. The two on the right have the North Polarity facing right.
A piece of glass serves as the stop to keep the armature from flying away from the magnets.
Step 2: Making the Armature
The armature is just a hollow piece of fishing pole the right size to fit inside the magnet holes. I used slightly larger Neodymium magnets (15 mm with 5 mm hole) on the armature than on the frame. The magnets on the left have North polarity facing left just like the support magnets. The ones on the right have North polarity facing right just like their corresponding support magnets. On the left side of the armature I inserted a drill bit to act as the pivot on the glass.
On the center of the armature I drilled out a piece of broomstick or large dowel to hold two smaller magnets which will interact with the electromagnetic coil. They must be the same polarity as the wiring of the coil (if is wrong just switch wires on the coil and it will be right). I mounted the magnets with screws to the wooden dowel.
Step 3: Electromagnet Driving Circuit
Here is a link to how to construct the circuit: http://www.trainelectronics.com/Pendulum/article.h...
The author does an excellent job of explaining how to do it.
Shown is the electrical schematic.
I use 6 volts to drive the circuit but it could actually be supplied by 4.5. Hope I don't burn something out.
Finally just set the coil under the armature, turn on power and give the armature a spin. Away it goes.
Good luck. Have fun.