Leonardo da Vinci designed a humanoid mechanical automaton in 1495 that could sit, wave and move its arms.
The machine is commonly called Leonardo's robot or Leonardo's mechanical knight. Leonardo prepared it for a pageant in Milan organized by Ludovico Sforza, probably as an impressive theatrical display rather than as a general-purpose machine. The robot wore an armor-like outer shell and was operated by a system of cables, pulleys and gears hidden inside.
Leonardo's original construction drawings were not known in complete form for centuries. In the 1950s, researchers found relevant sketches in the Codex Madrid I, and modern builders reconstructed the design. Those reconstructions showed that the mechanism could perform several humanlike movements, including raising its arms and moving its jaw.
The machine was not an electronic robot and could not act independently. In Leonardo's period, “robot” would not have been the word used; the term was introduced much later. It is best understood as a programmable-looking mechanical automaton.