What Leonardo da Vinci invention was a mechanical knight able to move its arms and jaw?

Leonardo da Vinci's mechanical knight was Leonardo's robot.

Leonardo designed the humanoid machine around 1495 for a festival commissioned by Ludovico Sforza, duke of Milan. The machine was dressed in armor and contained a system of pulleys, cables, gears, and levers. Reconstructions based on Leonardo's drawings indicate that it could sit, stand, move its arms, and move its jaw.

The robot was not an electronic machine and did not think independently. It was an automaton: a mechanical device whose programmed motions came from its internal arrangement. Leonardo's work connected his interests in anatomy, movement, theatrical machinery, and military engineering.

The original device has not survived, and historians do not have a contemporary demonstration proving exactly how far it moved. In 2002, roboticist Mark Rosheim built a reconstruction based on Leonardo's surviving plans. The machine is often described as the first humanoid robot, but that label is modern; Leonardo himself presented a mechanical knight rather than a modern robot.