The Concept
The idea was to create a switch the user can never see. I wanted to achieve this by allowing the circuit to complete only when the user closed their eyes. The second the eyes open, the switch opens and hence, the one controlling the switch can never know whether the switch actually ever made the light turn on or not.
The Circuit
I started by sketching out my circuit and then got to work on the bread board. The idea was to add the switch on the positive wire coming from the Arduino, so I got two pieces of aluminum to form the switch. Thus I attached the two pieces of aluminum on the connection between the arduino and the positive end of the LED. Then I attached those two pieces of aluminum to my eye lids, in a way that the switch closes when I close my eyes. This was a pretty challenging aspect as the jumper cables would weigh down the aluminum and the switch wouldn’t close properly. Eventually I ended up taping parts of the wire to my face and attaching the bread board itself to my face as well, so I can mitigate the gravity issue.
The Demo