Maker and astronomy enthusiast Görkem Bozkurt has built a GoTo telescope mount-inspired system that points and tracks any object in the sky using its celestial coordinates. The aptly named Star Track sports a 3D-printed structure along with a pair of Arduinos (an Uno and Nano), a gyroscope, an RTC module, two low-cost 5V stepper motors, and a laser pointer.
Many computerized telescopes have a type of telescope mount and related software which can automatically point a telescope to astronomical objects that the user selects. Called GoTo mounts. Like a standard equatorial mount, equatorial GoTo mounts can track the night sky by driving the right-ascension axis. Since laser pointers are a perfect way to point stars, I thought a laser pointer with a GoTo mount would be a perfect tool for locating stars and to track them.
First I had to design a two-axis mount.
1. 360-degree rotating axis for RA
2. A up-down axis for DEC
After aligning the RA axis with the North Celestial Pole, an Arduino connected with an RTC should be able to calculate and track RA with sidereal time. And you can adjust the two axes to the user input from a computer via serial.
But first I had to find a way to precisely point the mount to given degrees. The main idea was to use step motors and give them a specific step to take. But after a few tests that was not totally accurate.
Instead, I used a gyroscope placed on the laser pointer to track the degrees on the two axes, this way I was able to send a command to the step motor to start and stop the movement if necessary.
Intrigued? Bozkurt provides a basic overview of positional astronomy on his project page, along with all of Star Track’s 3D files, code and assembly instructions.