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Button Presser (for the keyboard)

  1. Sep 8, 2015 #1
    Is there any way I can use some type of spring / button pressing (for the keyboard) contraption to press two (or three) different keys at different intervals? Or does anyone know if some type of machine already exists? I know there are things called macros that can be downloaded that can press the buttons for you on set intervals (software), but what I need is a hardware / machine piece that can do this for me. Thanks in advance for any comments! (complete novice in mech engineering)
  2. jcsd
  3. Sep 9, 2015 #2


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    Welcome to PF.
    Behind each key is a pair of electrical contacts. If you bridge the two contacts it will appear that a key has been pressed, all without any mechanical interface.
    You could use a relay, a mosfet or an analog gate to make the connection. By using multiple contacts several keys could be pressed at the same times.

    A software solution would be called a wedge. It would insert key codes into the stream of data from the keyboard to the computer.
  4. Sep 26, 2015 #3
    Homer's little bird is exactly what I was thinking, and what I need. I need something mechanical to be able to press different buttons at different intervals, not at the same time (like one machine pressing x every 10-60 seconds, while another machine presses y every 15-65 seconds). Is there any mechanical thing I can buy, or make myself, to do such a thing? In reality, I can't find that bird and even if i had one, i don't think it would work well enough to actually press a button on the keyboard (not enough force).
  5. Sep 26, 2015 #4
    With regards to the relay, mosfet, and other thing, I googled them but couldn't find any useful information or products about them. Can you be a bit more specific? Health, science, nutrition & personal training are my fortes, not so well versed on electronics and mech engineering, hence my thread here.
  6. Sep 26, 2015 #5


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    Are you permitted to use software or electronics, must it be a mechanical key presser ?
    A mechanical device would probably need to sit over/on the keyboard and obstruct you pressing keys.

    A mechanical device might use a geared down motor fitted with a camshaft that rotates at say 4 RPM. Each cam would press a single key with a push rod. Cams could have more than one lobe if they need to press more than once per cycle.
    Cams might need to be driven by the one shaft so they are synchronous, or they will sometimes overlap their pressings.
  7. Sep 27, 2015 #6
    i'm sorry, i still don't understand. are these pieces i can buy online and put together easily? remember, i'm not well acquainted with the jargon of mech engineering, as much as i'd like to be. but yes, software is out of the question. now how can i buy these things you talk about and put them together? is there anyway someone can help me?
  8. Sep 27, 2015 #7


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    Yes we can help you. It is a free service we offer here at PF.

    But it is quite complex out here in the technology world. You need to ask very specific questions when you do not understand something. You also need to read the questions we ask you and answer them as accurately as possible.

    We first need to know better why you want to do it that way. Why mechanical and not electrical or software? Once we know what is needed we can work out the simplest and quickest way for you to make it work. Your question does not fully describe the application or the design parameters that are fixed or must be variable. For example, a device that presses keys needs to get power from somewhere. It also needs to press the right keys in the right order at the required rate. A machine to do that will be a bit like a very simple mechanical music box.

    Together, you and PF need to discuss/write the specifications so the best solution can be selected.
  9. Sep 28, 2015 #8
    well, it is for a test on my keyboard to play a repeating action on a game (but this game can find out software "cheating", which is why I need a mechanical device). software just simply cannot be risked for the sake of my account (don't want a deletion, etc). anyway, Power can either be gotten through an outlet in the wall, or batteries, I wouldn't know any other methods of making the device work, but I have outlets and batteries if either can be used for this device. With regards to time, for starters and basics, I definitely need to be able to press 2 different buttons at different rates. with regards to the time, it can be any spacing in between say a few seconds to no more than 5 minutes. As long as both buttons are pressed in SEPARATE orders (not simultaneously), than it would solve my issue. it's just to press 2 different buttons on a keyboard every few seconds or minutes as described above.
  10. Sep 28, 2015 #9


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    Devices for that exact use have been made out of lego:

    Youtube has lots of other example of cheap and easy devices like that.
  11. Sep 29, 2015 #10


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    Do you have access to any woodworking tools? Can you get scrap or new plywood?

    Let's consider a geared-down electric motor that rotates a big wooden disc above the keyboard. The disc can be plywood or chipboard.
    The outside edge of the disc could be driven by the geared-down motor with a rubber belt.

    Wood screws in a circle on one side of the disc project like pins, and so as they pass a bent metal plate, press a key through a push-rod. The number of screws and their position determines when during one turn of the wheel that the key will be pressed. The screws can be moved over time to change the pattern.

    On the same wheel, but on a different radius circle, or the other side of the disc, are more screws for another key. The screws are placed so no two keys will be activeated at the same time.

    A mechanism must be designed that pushes the push-rod onto the key as each screw passes. That need only be a flat metal plate with a bent end that is lifted and slides over each screw that passes. The mechanism is duplicated for each key that needs to be pressed.

    The keyboard fits in a frame that has a couple of cross-strips of plywood with holes, that guide the push-rods to the one key only.

    If you like the idea we can find a motor to drive it.
  12. Feb 7, 2017 #11
    I have a solution:

    This uses a relay to press a key at a given interval. I had to solder some wires to the control chip in the keyboard. Touching the wires presses the "4" key. The duration between key presses is determined by the amount of silence in the waveform. The next plausible solution would be to use a 555 timer circuit that powers a solenoid which is attached to the keyboard. This would be a non-invasive solution. A 556 timer would allow for two separate keys to be pressed at differing intervals.
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