sensor for key in small box

Other Hardware Sensors
1

Hi all, I need to detect if a key (normal size) is inside a small box or not. At the moment my only idea is using a break beam IR sensor, which works, but it's not really practical. Do you have any suggestion about other ways to accomplish this?

Thanks :slight_smile:

2

try googling proximity sensor non-ferrous (assuming your key is non-ferrous...all of mine seem to be...)

3

Hi,

thanks..never heard of those before..seems cool but I saw the prices are crazy and not worth for my project..

4

Did you look on eBay?

Other ideas:

  • Use a non-conductive box with two metal plates in the bottom arranged so the key will short them.
  • Monitor box weight.
5

Capacitive sensing?