New Approach to Integration of Form Deviations in the Analysis of Geometric Tolerances

— Tolerancing is an important step in the design process of a mechanism. There are two tolerancing approaches: tolerance analysis and tolerance synthesis. The principle of tolerance analysis is to verify the functional condition of the mechanism, for that purpose it is necessary to check the specific tolerances of each elementary part. Whereas the tolerance synthesis aim to calculate the specific tolerances of the parts forming the mechanism. The purpose of this paper is to develop a new approach of geometric tolerances analysis with integration of form deviations. For this we studied an example of assembly of two cylindrical parts (shaft and bore). The first step is to analyze the tolerances of the component parts assembly using the deviation domain method by neglecting the form deviations. The second step of this study is to analyze the tolerances with the same method but with the introduction of the form deviations, by using the discrete modal method for the modeling of surfaces with form deviations and applying a new algorithm developed for the simulation of our approach. Finally, we compared the two studies with and without form deviations through the calculation of a non-compliance rate (TNC)