Leonardo da Vinci’s armored fighting vehicle was intended to be powered by eight men turning internal cranks.
Leonardo sketched the vehicle in the late 15th century as a conical, armored platform mounted on wheels. Its sloped covering was designed to deflect attacks, while weapons could be fired through openings around the lower edge. The machine was moved by human power rather than by horses or an engine.
The eight operators would have worked inside the vehicle, using a system of gears and cranks to turn the wheels. The design is often called a tank, but it was not a practical modern tank: the crew would have had very limited visibility, and the gearing shown in the drawing may not have allowed the wheels to move effectively.
Some historians have suggested that Leonardo deliberately included a gearing error to prevent the design from being copied, although that interpretation is not certain. The drawing remains an important example of Renaissance military engineering and Leonardo’s interest in combining protection, mobility, and concentrated firepower.