electro magnetic levitation (pwm)

I build a magnetic levitatation device with a pwm ouput stage. I used a instrumentation amplifier to amplify the difference between the ref voltage and the infrared phototransistor voltage. And another one to offset this voltage between 1/3 and 2/3 of the supply voltage. A normal opamp(741) compares this voltage with a sawtooth. I used the byproduct of a 555as a sawtooth generator(on the capacitator). A capacititator parallel to the gainresistor was needed to prevent mechanical oscilation.
The frequency is about 2khz and is audible near the coponents around the 555 and near the coil. Power consumption of the coil is about 1 watt. See http://s158.photobucket.com/albums/t112/critiacrof/zwever/ for more details.

Category:

Science & Technology

Tags:

• electro
• magnetic
• levitation
• maglev
• pwm
• opamp
• breadboard
• hover
• ir
• infrared
• Gadget
• Elektronica

[phoenix2038]

i don't understand how this works, could you provide some explanation?

[critiacrof]

@phoenix2038 what do you not understand? It is basically an analog circuit that controls the current through an coil and hence the strength of its magnetic field. A metal object is suspended under the electro magnet. There has to be a balance between the gravity force on the object and the magnetic force from the magnetic field. If the coil is too strong the object will rise and there will be an change in the signal. The circuit will respond and lower the current of the coil...

[Darius12235]

good work now make everything smaller and more compactic and you wll have a hoverboard!

[critiacrof]

No that will just create a device that sticks to the floor.

[scrag10]

hover under a metal ceiling.

[critiacrof]

That's what I'm currently working on. A self lifting device containing a lipo and a micro controller. It is hold between to metal strips. Strong permanent magnets and a small airgap should make it possible for the electromagnets to control the device. However I doubt the PID controller will work the first time. I only need to find some magnets.

[phoenix2038]

@critiacrof thanks for the reply, it makes sense now

[blaargenheimer]

You need more light.

[08CJ09]

nice one fella

(:

[RobertoRebelato]

i see no levitation, but a controlled atraction

[transporter108]

i give lots of money for a hover board

[SPFAR]

do you also have an instruction video how you made all of this?

[SPFAR]

do you also have an instruction video how you made all of this?