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[on:]

I have this conductive rubber http://www.adafruit.com/products/519
I'm not quite sure exactly how it works. I also have an Arduino Uno and MP3 shield. I need to set everything up so that when someone tugs on a string (which I would like to connect to the rubber if possible)-it will play a sound

I guess I'm just not sure how to connect the rubber + resistor to the board.

Any thoughts/suggestions would be fantastic.

[Reply #1 on:]

I'm not quite sure exactly how it works.

Make a connection to each end of the rubber. Connect one end to ground and the other to an analogue input pin. Also connect a 10K resistor from the same input pin to +5V. Then do an analogue read to see when it is changed, that means you have pulled it.

[Reply #2 on:]

Mike is correct in how to get it to work, if you were curious how the science of it works, it's really simple. It works similar to capacitive touch works, what you are really doing is increasing the resistance. By getting closer or touching a surface it takes a longer time to get a reading, hence you can measure the time offset . However, unlike capacitive touch, here you are increasing the distance for the current to travel and in turn increasing the resistance. Also you are decreasing the size of the "wire" (or conductive rubber) so this might have an affect on the resistance too (not sure if measurable? someone can correct me if I'm wrong in this assumption)

check this out if you need an example of how to use it: http://arduino.cc/playground/Main/CapacitiveSensor?from=Main.CapSense