Leonardo da Vinci's Codex Atlanticus - Perpetual Motion Machine - Design 1

This perpetual motion design is one of da Vinci's most traditional. The wheel has twelve articulated arms with weights and free ends. The mechanical arms within the wheel are comparable to human arms in skeletal form and Leonardo included a sketch of a human arm at the bottom of the page. There is a ratchet that prevents the wheel from turning in the opposite direction.