This motor is the cornerstone of the mechanical side of the project, allowing the radio telescope to rotate its dish and tilt it in the y–z plane. The stepper motor, by itself, is pretty useless without a way to connect it to the dish. I plan to do this with a set of 3D-printed gears and some adapter pieces that trade speed for torque, allowing the motor to move the dish's heavy load.
Eventually, I'll make another circuit just like this one, because one stepper motor won't allow the dish to move in all the ways I want. Right now, the motors only allow manual movement via a potentiometer. Once the whole telescope is built, I'll modify the motors' code so I can track objects across the sky and map the Milky Way.
This is by far the most complex circuit I have ever built. To someone into electronics, it might look straightforward—a simple stepper motor build. I, on the other hand, am new to this and was afraid I'd blow up the decoupling capacitor every time I let current flow through the circuit. Despite that, I got through the development process, only causing a short circuit a few times. Now that's impressive.
This circuit is composed of an Arduino Uno R3, a stepper motor driver, a NEMA 17 stepper motor, a potentiometer, and a battery pack. The Arduino controls the operations of the circuit, a separate 12V battery pack provides power to the motor, a decoupling capacitor smooths out any voltage spikes (basically smooths out any noisy current and makes it safe for the electronics), and a potentiometer controls the voltage running through the circuit, which the Arduino then reads and alters the motor's speed and/or direction.
Very soon, I'll be 3D printing parts like gears and a case for all the electronics, so stay tuned for that. In the meantime, stay curious and cosmic.