Set up motion triggered circuit
The circuit on the wall is activated using the littleBits motion trigger. On a mounting board, connect a power to a motion trigger, then split the signal, one end going to a wireless transmitter and the other end going to an mp3 player and a speaker. I've attached the mp3 of Khaled + Rick Astley.
Set up servo-powered confetti dropper
The motion trigger will send signal to the wireless transmitter which will tell the receiver to turn the servo. On a mounting board, connect a power to a wireless receiver, then to a servo. Use the servo mount to place the motor onto the board. Attached the servo hub & arm to the motor and stick a cup at the end.
You can use whatever material you want to fall on your victim: confetti, water, glitter, tar, dirt, slime, diet mountain dew, origami elephants, spiders. You name it!
Hide a camera and wait
The motion trigger will play your mp3 & then the servo will drop whatever you want onto your victim. Record your prank and upload it to the littleBits projects page!