A question for the programmers: telescope/gps/stepper motors

Discussion in 'OT Technology' started by Mycophiles, Oct 13, 2008.

  1. Mycophiles

    Mycophiles OT Supporter

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    Ok, I have no programming experience outside of HTML. OK?

    Here's what I would really like to do.

    I have a telescope. A 12" Dobsonian (they are the big ones). I made the base for it myself that swivels in a circle and tilts. While it's nice and functional it is still a bit hard to maneuver when making small adjustments.

    What I want to do is get some stepper motors and attach them to the base to make the minor adjustments. I can do that. Not too difficult.

    The question is: while I'm doing it would it be difficult to drive the stepper motors with my computer while using a gps chip? Is there some way to make it 'point' to the sky where I want it like what you can find on the small telescopes on the market? While yes, I understand it's possible but would it be possible for ME to make this a winter project?

    Maybe someone could give me a rough estimate on what I would need to do to do this.
     
  2. mobbarley

    mobbarley Active Member

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    there is plenty of software that will do it already,dont ask me what because I have never done it but I know people who do. for driving the steppers you will need a parallel or serial port or some kind of usb stepper interface, and you will need a power supply and microstepping driver. you will probably also want some kind of reduction on the stepper -> telescope mount so you can get even more resolution.
     
  3. mobbarley

    mobbarley Active Member

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    I have used this one with microcontrollers and it's great, but unless you are happy wiring to a parallel port you will need something with more intelligence that can run from USB or serial.

    http://schmalzhaus.com/EasyDriver/
     
  4. Mycophiles

    Mycophiles OT Supporter

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    Wish someone would point me in the right direction. I knew going into this there was the arduino stepper. Here's an example.
    http://danthompsonsblog.blogspot.com/2008/09/easydriver-v31-tutorial.html

    But how to run it using gps information is hard to find information. I've just done searching tonight but haven't found anything. I did however find something that does it for 400$ :eek3: yea... right.

    http://www.bbastrodesigns.com/BBAstroDesigns.html

    I'm probably wrong but I think you could do this with the arduino board. I bet you could anyway. If anyone has any information please send it my way. Bobmarley.. be a friend and make some calls. :x:
     
  5. deusexaethera

    deusexaethera OT Supporter

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    The GPS info would only be used once, to determine latitude and longitude. Past that, the system would only track time-of-day and day-of-year to keep the telescope pointed at the same spot in the sky. The Lat/Long coordinates would effectively be constants in the formula, at least until you move the telescope more than a few miles.
     
  6. Mycophiles

    Mycophiles OT Supporter

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    Yea, the time/date is part of it. The telescope would also be moved about quite often.

    it's going to be a project. :hs:
     
  7. deusexaethera

    deusexaethera OT Supporter

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    I'm just saying you wouldn't need to feed live GPS data into it; you could just type it in. Might make it easier to build that way.
     
  8. mobbarley

    mobbarley Active Member

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