This came out of a toy that was a monkey with rubber arms. When you shot him like a slingshot he screamed louder than the sound of millions of people burning in errr umm Heck.
I wondered what made the jarring motion set the screaming off and tore one of them apart (it was annoying my parents when my nieces played with it at her house). That circular part is the sensor that makes the jarring motion of him flying set the sound off. It is a circular piece of metal with a spring inside. When jarred the spring touches the metal part and for an instant completes the circuit which starts the yelling until the sound file has been played fully.
This got me to thinking. What other cheap sensor ideas could be home made for cheap? I thought about using this sensor for a robot pet. When it ran into something (the sensor didn;t tell it to stop) it stops makes a noise and does an about face. Or maybe this detects when it is picked up or moved.
Anyone else got some home made sensor designs? Either a sensor that already exists, but can be made for cheaper, or a sensor that you made up on your own. If I can think of a prize I may make this a contest...