What humanoid automaton is Leonardo da Vinci believed to have designed in Milan around 1495?

Leonardo da Vinci is believed to have designed a mechanical knight in Milan around 1495.

The design was reconstructed from drawings and notes in the Codex Atlanticus. The knight was a humanoid armored machine whose internal system of pulleys, cables, and gears could produce movements such as sitting, standing, moving its arms, and opening and closing its jaw. It may have been intended for a court entertainment or pageant.

The phrase “Leonardo’s robot” is modern; Leonardo did not use the modern word robot. The machine is better described as an automaton, meaning a self-moving mechanical device. The surviving drawings do not provide every construction detail, so reconstructions necessarily involve interpretation.

In 2002, roboticist Mark Rosheim built a working model based on Leonardo’s plans. The reconstruction helped demonstrate that the proposed mechanism could plausibly create coordinated humanlike movements. It should not be confused with Leonardo’s separate mechanical lion, another ceremonial moving machine.