I need servo to move 90 degrees on switch action

Discussion in 'The Projects Forum' started by Tristow, Feb 2, 2014.

  1. Tristow

    Thread Starter New Member

    Feb 2, 2014
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    This thread is quite old.. hopefully I can still get help.

    I am also looking to have a servo move 90 degrees on a switch. I just need it to rotate 90 deg when I flip a toggle switch, and then move back 90 deg to the original position when the toggle switch is flipped again. I do believe it could be wired in a way with a "inline transmitter" of sorts. Where the transmitter would send (what I think would be) a pulse of 600ms off, 1800ms on?

    To be clear I don't really know anything on how servo code works. If it helps at all, I am fluent in CNC g-code. Thanks in advance!
     
  2. Alec_t

    AAC Fanatic!

    Sep 17, 2013
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    Welcome to the forum.
    You would have been better starting your own thread rather than resurrecting an old one.

    Is this a standard hobby RC servo?
    Do you know the angular range of the servo?
    Does the toggle switch have a centre-off position (i.e three positions in total), or just two positions in total?
     
  3. Tristow

    Thread Starter New Member

    Feb 2, 2014
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    The "useless machine" or "leave me alone box" movement is basically what I need. I attached a few pictures of a kit you can buy online. The item I circled in yellow is what I'm wondering about. If that transmits pulses, then I think that's all I need to do this. I already have servos, switches, and a power source.
     
  4. Tristow

    Thread Starter New Member

    Feb 2, 2014
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    Yes, it is a "standard" rc servo. If im not mistaken, it should be a 90 deg angular range. It's off a steering servo for a rc car. And the switch would be a two position.
     
  5. John P

    AAC Fanatic!

    Oct 14, 2008
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    I don't see the component or assembly that would actually drive the servo. You'd want something with an oscillator which would produce variable pulse widths according to whether the direction is "open" or "closed". The item you circled looks more like a magnetic reed switch to me, something to detect whether the box is open or not, and the magnet that triggers it might be the washer that's near that part--it could be a magnet. It's not clear though, whether that white rectangular thing is just a switch with 2 wires coming out of it, or if there are more wires, so maybe it has components inside. Anyway, you can't run one of these servos with just switches; you need some electronics.
     
  6. KMoffett

    AAC Fanatic!

    Dec 19, 2007
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    Google: 555 servo driver

    Ken
     
    Last edited: Feb 2, 2014
  7. Alec_t

    AAC Fanatic!

    Sep 17, 2013
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    Here's how I'd do it:
     
  8. THE_RB

    AAC Fanatic!

    Feb 11, 2008
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    I would suggest a change to that. You are using an SPDT switch so when the switch flips it will go temporarily open-circuit so the signal will stop or glitch, which might make the servo jerky.

    If you wired one resistor in permanent, and used a SPST switch, it would give the same two states but would be without the glitch.

    One resistor value would need to be changed, but then it could be a trimpot anyway to give some adjustment to the servo movement angle. :)
     
    Alec_t likes this.
  9. Alec_t

    AAC Fanatic!

    Sep 17, 2013
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    Good idea, RB.
     
  10. Bernard

    AAC Fanatic!

    Aug 7, 2008
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    Might review old post " Servo Pop-Up", MLD, 03-04-13. Page 11, post 107, 111,& 113.
    Also Mc'er by thatoneguy
     
    Last edited: Feb 3, 2014
  11. MrChips

    Moderator

    Oct 2, 2009
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    Belatedly, I moved this thread to its own thread.
     
  12. inwo

    Well-Known Member

    Nov 7, 2013
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    Where are you in WI.?

    This subject rung a bell. I dug thru my junk pile from 20 years ago, and came up with three 555 servo driver boards with the 0 and 90 degree pots on them.

    I'd put one in an envelope for someone who would use it.

    They were built to connect with a switch for 90 degree motion. On-off.
     
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