Folio 1062 recto of Codex Atlanticus and the perpetual wheels in Codex Forster II

In folio 1062 recto (ca. 1497-1500) of the Codex Atlanticus, Leonardo presents the various mechanical wheels that he had studied thus far, featuring oscillating arms and running balls. He concludes his study by proposing a new perpetual-wheel system, set in motion by balls rolling from one end to the other of two straight channels interconnected to form a continuous course. These models are also reproduced and explained in the Forster II.

Leonardo da Vinci, Codex Atlanticus (BAM), f. 1062r - Studies for the design of a perpetual wheel
Leonardo da Vinci
Milan, Veneranda Biblioteca Ambrosiana, Codex Atlanticus, f. 1062r
Leonardo da Vinci, Codice Forster II, f. 92v - Riflessione sull'impossibilità del moto perpetuo
Leonardo da Vinci
London, Victoria & Albert Museum, Codex Forster II, f. 92v