In Codes Madrid Leonardo proposes numerous solutions on how to transform the motion by rotation in alternating and vice versa. This is one of the many known as crank-rod system. Leonardo reserves sharply lot of space to design two of the pillars of beloved mechanical engineering, namely the processing and transmission of motion: very significant are the mechanisms for watches, the transmission chain, the various motions and articulated in textile engineering. Leonardo gives an example of the transformation of continuous motion in motion alternate, taking as their model a textile machine, where, beginning with the rotation of the crank motion, it is possible, through the movement of a lever and a rod, which acts both inside and outside l ' tree cable, wrap uniformly a wire around the spool.
C. 1478 / 80. Code of Madrid