Light Switch with ZWave and Bare Conductive Paint

Hi!

My idea is to create a light switch that is drawn on the wall, and when touched, it will turn on/off a switch controlled via ZWave protocol.

The idea comes from the Bare Conductive Touch Board https://www.kickstarter.com/projects/863853574/touch-board-interactivity-everywhere

Unfortunately, they do not have WiFi integrated, and the shields are pretty expensive.

So, the technical question is(
For simplicity, Bare Conductive Paint acts exactly as a wire, so we will call it a wire.): How can I make the Spark IO input know when I touch the wire with my finger? Do I need an extra cip or something? How can I do it as simple as possible?

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ST (who makes the STM32 micro-controller) has some documentation and a library for using the STM32 as a capacitive touch controller:

I haven’t tried to do this myself but it is possible to do it with just the MCU. That said, I believe it is much easier to purchase a chip that will handle the capacitive touch sensing itself and has an I2C or SPI interface.

I would not try and do capacitive touch directly via the web GUI, at least not for a while yet, once all the loose ends get shaken out.

Until then, try using something like these instead:


Now, neither may work very well with just some random conductor on a wall, but there’s only one way to find out !

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