What Leonardo da Vinci invention is often called the world's first robot?

Leonardo's robotic knight is often called the world's first robot.

Leonardo da Vinci designed the humanoid machine around 1495 for a pageant celebrating the Duke of Milan, Ludovico Sforza. The machine was probably constructed in armor and could perform limited human-like movements, including sitting, standing, moving its arms, and opening and closing its jaw.

The design survives in Leonardo's notebooks, especially the Codex Madrid I, rediscovered in the 1960s. It used cables, pulleys, gears, and a programmable cam mechanism inside a suit of armor. The knight was not an autonomous robot in the modern electronic sense, but it was a sophisticated mechanical automaton.

A modern replica built by researchers and engineers in 2002 demonstrated that the design could work. The invention is sometimes confused with Leonardo's mechanical lion, another automaton associated with court spectacles.