Flapping-wing machine with a vertical bearing

This drawing belongs to the first series of machines Leonardo devised for mechanical flight. The highlight of such machines is a wing structure, which is operated very fast by the combined action of human strength and dedicated mechanisms. The flyer, standing in an upright position, operates the two stirrups, which, in turn, power the wing structure via a rope and pulley system.
Codex Atlanticus, sheet 749