The achievement of high quality (Better-Best quality) and continuous research in minimizing waste (no Muda) are two of the fundamental points of the ideology of Lean production. ROJ.srl, careful to these considerations, has invested in this thesis for the research and design of an automated system able to test the quality of components purchased from external companies. In particular, the thesis focused on the defects and noise of the gearboxes purchased, aiming to have a system for the detection of gearboxes non-compliant, avoiding the use of these units in the assembly process and thus, improving the optimization of quality and waste of components at the same time.