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Thread: a little help for a project way to ambitios for me

  1. #11
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    Jan 2006
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    Akron, Ohio USA
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    Take a look at how a clothes washer or dish washer cycle system works. It a very complex cylindrical switch with many contacts. It's also motor driven to create the time base for the cycled events. I would start working with PVC pipe and copper foil made for leaded glass work. You could use gold jewelry wire to make the contact whiskers. You could even get the copper gold plated.


    James.
    Last edited by James Lehman; 08-22-2008 at 16:44.

  2. #12
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    Dec 2006
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    Riverside, CA
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  3. #13
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    nerdtown, USA
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    Put a small microcontroller (for example, an Atmel ATmega16 would be perfect) in the middle with a wireless chip like the Nordic VLSI nRF24L01. Have it control the LEDs. Then your only problem is sensing the zero degree mark, which can be done using a Hall effect sensor and a small magnet attached to the frame. You'll have to power the thing either with slip rings (kinda sucks, hard to get right) or batteries on the rotor (also sucks).

    You will need to learn:

    - how to build microcontroller circuits
    - how to program microcontrollers
    - how to make the whole thing robust enough to run for a couple of hours without breaking
    - how to stop people getting maimed by it when they try to touch it (and they will).

    This is not a trivial project- you might want to try something else first...

  4. #14
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    Feb 2008
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    They are called POV displays

  5. #15
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    Apr 2005
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    SOUTHAMPTON U.K.
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    Checkout Spacewriter not cheap though




  6. #16
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    Nov 2007
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    Cairns, Australia
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    Ive built a few of these before, they used to come as kit form and just do some simple LED patterns as it span. They had slip rights for power, and 1 slip ring for a "pulse" signal so the timer chip knew where it was.

  7. #17
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    Jul 2007
    Location
    Brooklyn NYC
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    or you could try some thing like this

    http://www.ladyada.net/make/spokepov/

  8. #18
    Join Date
    Mar 2006
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    Quote Originally Posted by soforene View Post
    OMG !
    That's spooky !
    I have one of these in my Garage.


    By an amazing coincidence I have built in a small add on which turns a bit of dowling with LED's on.
    It's quite a show.

    I may bring it to the next meet (if I can get a trailer large enough and a PP9 for the LED's).
    Egads, I wondered where THAT went...

  9. #19
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    Mar 2006
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    Quote Originally Posted by joebone View Post
    i was thinking of something that might spin a little slower and i could walk the LEDs in from the outside as its spinning around. and turn on 2 of them to make 2 circles. but the clock is really cool and helps allot with this project. someone suggested i use wiper contacts. but i would have to use one for every bulb. gotta be one board in the middle and one board mounted on the other side of some kind of rotating contact or something.

    i think....lol im really shooting in the dark..lol
    If you're serious about this, look up two-wire control systems. They power the circuit on the far end, and communication is based on sensing the difference in current. It isn't the best way to explore the method but it might work, and if you manage it you'll have learned some very useful stuff. Bear in mind that you'll need at least a microcontroller circuit on the hub, and lines to each LED used, and a connection through the axle and a slip ring fitten on the hub or shaft laid on an insulating ring. And you won't be able to run it fast, or all hell breaks loose. Just strobing the LED's at modest speeds could be very cool, specially if you manage a chase light, so what you'd see would be a spiral of strobing points.

    Probably more fun to make a laser comtroller though, which could do this and plenty more.

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