Cranks powered the wheels in Leonardo da Vinci’s armored vehicle design.
Leonardo designed the fighting vehicle in the late fifteenth century, probably while seeking military employment from Ludovico Sforza, the Duke of Milan. The machine had a conical armored shell and was intended to move across a battlefield while its occupants operated weapons through openings in the covering. Its appearance has led to the popular nickname “Leonardo’s tank.”
The proposed vehicle was not a modern tank. It had no engine, suspension, rotating turret, or enclosed track system. Instead, people inside would turn cranks connected to the wheels. The surviving drawing also contains a gear arrangement that would make the vehicle unable to move as drawn. Historians debate whether that was an intentional error or a drafting problem.
The design nevertheless anticipated several later armored-vehicle concepts: protection for the crew, mobility, and weapons mounted around a strong body. It remained a paper design during Leonardo’s lifetime and was never built as a Renaissance battlefield machine.