The Empires of Asia and Europe were already industrialized and mechanized in ancient times. The Grindery is based on an actual armored war machine from history called a siege castle. Invented by Epimachus in 304 BCE, it uses capstans, powered by people or draft animals, to turn the wheels of a massive 10 story castle covered in iron plates. This enables the vehicle to reach 10km/h, considered an incredible speed for such a large machine. The siege castle is also armed with ballistae and catapults capable of firing flaming spears with pieces of burning cloth soaked in tar or oil tied to it or fire pots filled with tar or oil that have its outer surface or a wick lit before being hurled at the enemy to shatter and burst into flame upon impact. These vehicles fire their artillery through ports that can be covered by closing armored windows. They later started using exploding spears and shells filled with gunpowder starting in the 900s, cannons in the 1100s, and rockets in the 1300s. This, and the other armored vehicles listed below, were steered using tillers which were levers connected to pivoting front axles to turn them.
Below is an image of the siege castle:
The Chinese inventor Lu Ban, also invented his own armored war machine in the 500s BCE, called a siege tower, which was also powered by cranks or capstans driven by humans or draft animals, and covered by thick wooden panels:
The Chinese later armed these siege towers with cannons, starting in the 1100s, or rockets, starting in the 1300s:
Moravian inventor Jan Zizka also invented an armored vehicle in 1420 called a cannon wagon, that was pulled by draft animals or powered by cranks or capstans, and was armed with cannons:
The artillery in Jan Zizka's war machines were breech loading swivel cannons that used swivels to open and close breech loading ports where the gunpowder and shells were inserted:
