A simple human Treadmill powered Medieval Water Crane model I made for Foundation City-Builder.
A treadwheel, or treadmill, is a form of engine typically powered by humans. Uses of treadwheels included raising water, to power cranes, or grinding grain. It was primarily used during the Roman period and the Middle Ages in the building of castles and cathedrals. The often heavy charge is lifted as the individual inside the treadwheel crane walks.
The specific model has been inspired by a number of images including the following:
http://www.vicnewey.co.uk/mills/mills_011.htm
https://www.handshouse.org/czech-crane
You can find the full mod with the Lua code used for animating it on mod.io: https://foundation.mod.io/water-crane
Note, the model has been originally released on Github under a GPL 3.0 Licence, that licence still applies to any downloads from sketchfab and a copy can be found here: https://www.gnu.org/licenses/gpl-3.0.en.html