We made a useless machine with Arduino. This is how we did it so you can make one at home as well!
What is a useless machine?
A useless machine is a box with a button (switch) on it. When you press the switch, the machine starts, and a mechanical arm presses the switch off, which in turn shuts off the machine. So it's a machine that turns itself off. Sounds useless? It is. It's a lot of fun though if it works.
The things you will need will be:
Materials for the box (the box should be 22 cm's long, 14 cm's tall and 14 cm's wide)
4 Batteries 1.5V (the power source) and a box for these batteries
Arduino board + breadboard with cables
2 Servo motors
Mechanical arm to attach to the servo which presses the switch