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I am using an Arduino Uno and would like to simulate a capacitive tap with zero human contact on my iPhone 5 screen.

What seems to work right now is putting a coin on the screen and connecting the coin to a power source (such as Digital I/O Pin) and when voltage is sent to the coin it triggers a "tap" on the screen. Is this safe? Is there a better way to do this? I just read somewhere else that any grounded conductive object should work. Is it better to ground the coin or to connect it to a power source? Also, how can I stop sending current to/grounding the coin so the simulated touch is stopped. Right now, I can't get the arduino to stop "touching" the screen.

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When I used to work in touchscreen development, we had a couple of methods to achieve exactly that. The first was to interrupt the connection to ground with a miniaturised relay. The shorter connection between the relay and the "finger" the better. The other method was to use an RC servo, which simulated a mechanical finger. Both worked, but obviously the relay was faster acting.

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  • \$\begingroup\$ Can you provide a link to a miniaturized relay I could use? Would this work: amazon.com/WINGONEER-KY-019-Channel-Module-arduino/dp/… \$\endgroup\$
    – Caders117
    Commented Feb 23, 2019 at 0:11
  • \$\begingroup\$ Or this: amazon.com/Tolako-Arduino-Indicator-Channel-Official/dp/… (I think they're the same thing, just this one has better reviews) \$\endgroup\$
    – Caders117
    Commented Feb 23, 2019 at 0:20
  • \$\begingroup\$ pretty much any of the Omron G6K would work, but all you reall yneed is just a small relay. digikey.no/products/en/relays/signal-relays-up-to-2-amps/… \$\endgroup\$
    – Elmesito
    Commented Feb 23, 2019 at 8:35
  • \$\begingroup\$ This might work in some cases, but it is not a general solution. At the least, if you are going to use a servo, use a touch stylus determined to work with the target screen. \$\endgroup\$ Commented Feb 28, 2019 at 21:28
  • \$\begingroup\$ Test environments use a small surface area metallic probe with a small reed relay to do this. It's very common. I've seen both multiple fixed position probes and 2D positioning systems used (no Z involved). Typically the 2D positioning is used where you need to emulate screen swipes. \$\endgroup\$ Commented Feb 28, 2019 at 22:23

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