The characterization and specification of functional requirements and geometric tolerances in design

In the process of mechanical design, tolerances are of crucial importance because decisions related to tolerances can have a decisive influence in terms of the product cost and quality. At present, there are numerous approaches and investigations related to the analysis and/or synthesis of tolerances and the modelling of assemblies. In this article, we look at the basic essentials required to deal correctly with the functional requirements and the geometric tolerances at the specification stage of the design process, in such a way as to guarantee the subsequent computer-aided tolerance synthesis at the basic and detail design stages. To achieve this aim, we developed an experience-based method. Applying this method to a set of real cases provided by the Industrial Equipment Design Centre at the Polytechnical University of Catalonia has enabled us to adjust the method to suit the application. The objectives proposed in this work are reached by the obtained results through applying the method.