Capacitive Touch Sensors

I'm most definitely a newbie and know little to nothing about electronic circuits.

I'm looking for capacitive touch sensors that are adjustable. A sensor where I can adjust or specify the threshold of capacitance required to activate a switch.

For example, if my capacitance is measured at 100 and my five year old son's is measured at 50, I could set the threshold to 75 so it will only work when I touch it but not my son. Make sense?

Any and all help/info is greatly appreciated.

Nice idea, although I am also a newbie and cannot offer information I would be interested to know if this is possible.

Unfortunately, they are not precise enough for that. For instance - if you take your shoes off, a capacitance switch will read about ten times higher than it does with your shoes on.

https://www.freescale.com/webapp/sps/site/prod_summary.jsp?code=MPR121

https://en.wikipedia.org/wiki/Touch_switch

You won't be able to distinquish between a child and and an adult. You would be better off going for a finger print reader.