I think tracking mechanisms can be as complicated as one cares to go. A TEFC AC or DC gearmotor or a C-band satellite dish "jack" linear actuator could be sources of power.
When I was looking at various solar devices online years ago (just out of curiosity) there were fairly simple motorized trackers, and others controlled by software on a PC or a home-built circuit, and these were just DIY setups.
I think there is a lot of gear available for amateur astronomer telescopes which could possibly be used as a building block for a tracking system.