Electromagnetic Floater

This Instructable will show you how to make a device that can float almost any object with a magnet in it.

It is much like the floating globes you can buy, except it works by balancing the forces of permanent magnets with electromagnets, rather then simply using combinations of permanent magnets.
This is done by using a microcontroller and an IR sensor to detect where an object is floating below. Then based on a set value, the microcontroller uses the electromagnets to to hold the floating object at a given height.

The place the object floats at depends on the weight of the object and the power of the magnets in the object. The height is set by holding the object under the magnets and sensor and pushing the button.
The object floats at the point where the force of gravity down equals the force of the magnets pulling up, which allows it to use non-industrial electromagnets and less power to float. The program also dynamically adjusts so the object is always at the perfect height.

I decided to make the electromagnetic floater because I have always been fascinated by the floating globes in the store, but I never wanted to pay their prices, and I never liked how they only floated objects that you had to buy or came with it. So, I decided to make my own that could float anything with a magnet. The results are what you see here.

Step 1: Materials

Materials:
- ATMega168 Microcontroller
- 1 16-20 MHz Crystal
- 28 Pin Socket
- Dual Full H Bridge IC
- 1 Power NPN
- 2 Electromagnets
- 1 Bicolour LED
- 2 IR LED
- 1 IR Photodiode
- 1 5V Regulator
- 2 Leveling Capacitors
- 1 SPST Switch
- 1 NO Button
- 1, 470 Ohm Resistor
- 1, 5 Ohm Resistor
- 1 Universal Breadboard
- 2 Cases
- Plexiglas
- Solder
- Hot Glue
- Steel Wire
- Vinyl Tubing
- 3 or more 1/4" diameter x 1/4" thick rare earth magnets (for the base)
- 2 or more 1/2" diameter x 1/8" thick rare earth magnets (for the objects)

Tools:
- Soldering Iron
- Hot Glue Gun
- Desoldering Pump
- 3rd Hand
- Plexiglas cutter

Comments

[0505STAZ]

Could you get the items part numbers? I am trying to make it and it is hard to find it without it.

[nerd12]

would it be possible to make this into a hand held version by reversing the magnets to it is being pushed up rather than pulled up? this could be made into a glove similar to an iron man repusler. it will have to be a powerful electromagnet, but is would be Definitely worth it! the effects are ENDLESS! Magneto! Hadoken! Deathstar! dragonball!(have not been a fan of the last two, so no clue :P )
what do you think?

[Super_Nerd]

This would look cool levitating ferro-fluid.

[AJMansfield]

I totally agree. Although you'd need a permanent magnet for the ferrofluid to glom around, since it can only hover things that are already magnetic. Or invent a type of ferrofluid that naturally has its own field.

[AJMansfield]

Use it as a thermometer or something; have the hover height depend on the temperature.

[mb inventor]

wow

[Dantex]

So if I got this correctly - the circuit uses the feedback of IR led-s to regulate the current going trough the coil to keep the downward force constant

but then why 2 electromagnets?
can you label the pins on your H-bridge symbol (never seen that symbol, so I don't know what pins do what)? what do 2 Leveling Capacitors do? it is a bit complicated to understand
I would like to make my own but it isn't very straight forward

[scci]

he used an unsusal sybol but i found it on this page

http://www.adafruit.com/datasheets/l293d.pdf
took me 3 months of looking be happy :)

[Dantex]

Thank you very much!!

[Bertmci]

Hi every one i would like to know how many turns should be used on the electromagnets and also what size wire
Bertmci

[AdielFernandez]

This is a great project! I'm hoping to recreate this with a more powerful setup since I'm hoping to levitate a slightly heavier object. However, in looking at a bunch of EM levitators, I see people either use a hall effect sensor or an optical setup like your to sense position of the object. This one seems much simpler than having to measure the magnetic field with the hall sensor, are there any drawbacks from it? What are the benefits of using the hall sensor instead?

[connormarve]

Can anybody tell me how exactly to assemble the electronics, as the tutorial is to advanced for my primordial brain.

[penghars]

How about if you changed the microcontroller and LED and thar stuff with a potensiometer.... Could it still work??

[h2osteam]

you can try to use negative feedback opamp and some analog circuit design to achieve the same thing. i believed.

[bears0]

no it needs to compensate for height. if the object being levitated is too high it turns off the magnet and vice versa. with a potentiometer it wont be able to automatically adjust. also it would be impossible for someone to to control it because they couldn't react to the changes fast enough.

[1dog789]

what is the zipped file?

[JGsoldier]

where would you get all of the materials?

[CMNDR]

Anybody ever figure out how or where he got his coil, or the specs of the coil so I can make something similar?

[Cybot Rules]

It reminds me of the look of some coils i grabbed from the driver coils from a floppy drive motor.. Wortha look anyway and off memory there is 6 in one drive :)

[CMNDR]

Those look really big to be located in a floppy drive. I could see one maybe but not six.

[CMNDR]

Exactly how many transistors or voltage regulators are you using? Your schematic calls for one but I see two in this picture. Also on later picture I see another two are located underneath the board itself. What are these used for or are they the ones that were located on the top but have been moved under the board.

[macnomad84]

I dropped a floater in my toilet this morning... Now i have to build another one.

[blinkyblinky]

Can I use an Arduino?

[amruth]

can i know what type and gauge of wire u used for the electromagnet.

[tledgerwood]

saw the name and couldn't stop laughing, imagining a magnetic poo and its uses

[vzdemon]

that's really cool, but i wonder if i can use the Arduino2009 instead of create a new MCU.

[samirsky]

1. Is it possible to get a parts list?
Excuse me if this was already posted. I couldn't find it. I am too much of a newbie to know what to buy when I see "Power NPN": there are so many transistors.

2. Is it possible to drive the electromagnet (via transistor/bridge) with the PWM output of the Arduino? Or does this higher frequency switching cause the magnetic field to not behave properly? I ask because this project has inspired me for another project I want to do (and post on instructables, of course).

[lurkingdevil]

I too would like to know the answer to question 2.

How does the arduino control the coil in this instructable?

[rkr]

How exactly do you load a program onto a microcontroller? I am unfamiliar with this task and I think that you should have included some instructions on it.

[antonad]

ya, me to, need to know, and also the value for capacitor and transistor?

[16zzundel5]

You need to program it with an arduino- I can do one and send it to you for tthe price of the microcontroller and shipping. If you have the microcontroller already, send it to me and I can program it for you for the cost of me sending it back.

[kucloth]

Well... not exactly. Arduino is a special micro hardware/software system based around the atmega micros and is actually not nearly as useful as everyone seems to think it is. To program a microcontroller, you need a compiler program to write the code on and actually load it into the micro. (tons of free ones like WinAVR available online, just Google it). You also need a cable to connect the port (serial, parallel, USB, etc) on your computer to the micro to program. It's not that complicated, but it does take a bit of practice. I am sure there a few instructables that can teach you how among many websites.

[theexpert]

it should be like putting music on your mp3 from lime wire and or frost wire just download it to your computer then put the file into the micro-controller after plugging it in at least with arduino you can put it into the comp idk about others

[robomatt1999]

This would make a nice futuristic pecil holder : P

[bkrishnan1]

its very nice can you send which electromagnetic coil used

[TheIronHobo]

is it strong enough to hold a pen?

[tech industries]

Would the math involved in the Arduino code need to be modified for every specific coil? My electromagnets are not identical to yours, so with the change in size/strength where in the code would the modification (if any was needed) take place?

thanks

[pianoman2011]

i was thinking... since the power jack is a 1/8" audio jack, if you used a jack converter and plugged the device into a cd player/iPod, would the change in the electrical signal when you play a song sort of move the magnet with the music? would an amplification system be needed to strengthen the signals to sufficiently power the device, if this was all possible?

[J_Hodgie]

not really, it needs a constant power supply and more power then the audio feed could supply.

[scraciun]

hello i really need your help:) you didn t say anything about the program