It is a very simple battery less LED toy for kids using a stepper motor as power generator. As you know if you provide power to a DC motor it will rotate. But if you rotate a DC motor it will provide power. Out of this concept we have made this toy. Stepper motors provide more power than ordinary small DC motors at low rotational speed. I have connected two LEDs ( Red and Blue) with two coils out as per the given circuit. The motor shaft is attached to a handle. The wires connecting the LEDs and coils are approx 6inch long. There is a weight at the end of the wire where LEDs are connected. You can rotate this toy y holding the handle and the LEDs glow sequentially. Because of persistence of vision you can light ring.
Step 1: Step by Step Video Tutorial
click to get detail video instruction ( video )
Enjoy Making :)