Freeform circuits are all the rage these days, and do a great job of combining the cold nature of electronic components with the warm creativity of art. They are, however, more difficult to assemble than an equivalent circuit built on a breadboard or PCB, because the wires need to be bent precisely in three dimensions to achieve the “sculpture” aesthetic. Usually, that becomes more impressive the more complex the circuit is. But in the case of Redditor Psuedohim’s hand-cranked LED, the charm is all in its minimalist simplicity.
This freeform circuit sculpture was made using just four components: a red LED, a capacitor, a resistor, and a small 5V gear motor. A hand crank is attached to the output shaft of the motor, and the gears translate the relatively slow and high-torque hand cranking into a high speed turning of the motor. Because electric motors and electric generators operate using the same principles, that cranking generates enough current to light up the LED. This does mean that crank has to be rotated in the correct direction in order to avoid damage to the polarized capacitor, but that’s a small price to pay for the simplicity of this circuit.