Tracking satellites with custom hardware based on stepper motors. A blog description of the project can be found at https://www.la3t.no/automatic-satellite-tracker/
The construction of the rotator is based on the SatNOGS project found here: https://gitlab.com/librespacefoundation/satnogs/satnogs-rotator/tree/master
The controller is based on the work by Elwood Downey found here: http://clearskyinstitute.com/ham/AST/. The software is based on this repo by Bjoern Kerler: https://github.com/bkerler/AutoSatTracker-ESP