An aircraft tracking system has been created using an inexpensive camera and basic microcontrollers, according to a recent post on Reddit.
The system uses a cheap rotating security camera, with its internal stepper wires connected to an Arduino nano in order to move the motors.
A Raspberry Pi is used to provide local ADS-B data to detect nearby aircraft and determine its location, after which the Arduino Nano moves the camera to the correct angle to capture aircraft information such as azimuth, elevation and distance.
The creator of the system has made the software open source, and information about the construction of the tracker is available on a Hackaday GitHub page.
As well as tracking planes, the creator also suggests a star tracker could be used following a similar principle.