Diagnostic approach to identify, analyze and improve a sports car retractable top

The master’s thesis here presented is the result of the collaboration between the ”Uni- versità Degli Studi di Padova” and the product quality department of Maserati in Modena, where the MC20 and MC20 Cielo are exclusively manufactured. The purpose of this study is to investigate the assembly methods of the rooftop in the Maserati’s convertible model MC20 Cielo and to find a way to improve the overall quality of the final product. A preventive and diagnostic approach, already in use by the Maserati’s Quality Control team, was adopted. This method allows to identify the cause of the problem, which could be due to design, production or supplier. The analysis shows a common root cause attributable to various non-conformities relative to the positioning of the hood. In particular, the adopted jig was over-constraining the rooftop and the placement method of the front receivers was not accurate enough. Changing the positioning along the production line of the jig, unlocking some degrees of freedom of the jig and using a fast control template for the receivers are just some changes that allowed a significant improvement in the overall quality of the product.