by MidnightMaker @ instructables.com:
This is a Solar Tracker. A full size, internet cloud connected, smartphone accessible Solar Tracker built mainly from 2x4s and plywood, employing wooden peg gears, recycled curtain poles, nuts, bolts and threaded rod. The solar tracker uses a home built electronic controller incorporating WiFi, stepper motor drives, accelerometer and magnetometer. The tracker was designed to drive a full size 90W panel in azimuth and elevation. The gears driving the tracker are wooden peg gears commonly used in the 16th century. The gears were designed using modern 3D CAD (Solidworks). Connecting the wooden peg gears to the internet cloud just seemed like the right thing to do. This is not a waterproof design – you will need to consider modifications to waterproof your derivative design.
Solar Tracker in the Internet Cloud – [Link]