Tolerance Analysis: A New Model Based on Variational Solid Modelling

In mechanical fields products are usually made by assembling many parts. The dimensional and geometrical variations of each part has to be limited by tolerances able to ensure their manufacture, assembling, interchange-ability and a certain level of product quality. The tolerance analysis is the fundamental tool to foresee the effects of the tolerances assigned to the single components on the whole assembly and to optimize its quality-cost ratio. This work presents a new tolerance analysis model able to overcome the limits of the actual ones. It is based on the variational solid modeling and on the simplified hypothesis that each feature maintains its nominal shape. Its application is general. It allows to perform analysis by both worst case and statistical approaches. It may consider all the tolerance kinds, the Envelope and the Independence principles, the interaction among the tolerance zones and the joints with clearance among the components.