Star / Moon Tracker

Point a small telescope at the moon and it drifts out of view in under a minute. Mounts that track the sky cost more than the telescope. The tracker is the cheap version of that: a motor that turns the mount at the speed of the sky, so the moon or a star stays put in the eyepiece, on a tripod you already own.

A barn-door mount. Two plywood plates hinged at one edge, a threaded rod between them, and a stepper motor turning the rod so the top plate opens at exactly the rate the sky turns. The telescope sits on the top plate on its own ball head; the bottom plate bolts to any camera tripod.

An Arduino Nano, a DRV8825 stepper driver, a DC-DC buck to run the logic off the 12 V supply, and headers for every switch and LED on the panel. Laid out so a stranger could assemble it from the silkscreen alone, which is what turned it from a project into a product.

Speed on a slider, direction on a rocker, power, and a big green start button, each labelled in the plastic so you can find them by touch. A fan behind a grille keeps the driver cool. The box and lid were drawn in CAD and printed, with the cutouts sized to the exact parts.

This was the first thing I made that someone else paid for. Getting there meant a board a stranger could assemble, a box that didn’t need an explanation, and a price that made sense next to the telescope it sat under. The tracking was the easy part.