New Trends in tolerancing, the GD&T French Research Group point of view

The contributions of the French community in the field of tolerancing are measurable by the interest and the research works they generate with foreign researchers during the last thirty years. To quote only the main results being the object of new studies we can remind the modeling of the geometrical deviations by the small displacements torsor (SDT) for design, manufacturing, assembly and metrology activities, the modelling of the nominal geometry by the TTRS theory, the simulation of the three-dimensional chains by domains, the expression of the tolerance specifications and the measurement processes from the model GeoSpelling retained by ISO for the future standards in the GPS field. These works, even if their applications contribute to meet the industrial expectations, do not naturally allow still answering all the new challenges the design and the production of products are confronted too. The communication at the world level, the global vision for the control of the geometrical variations along the product life cycle (PLM), the quantification of uncertainties and risks from functional needs to product use, the link cost/tolerancing, the virtual reality, and the identification of the key parameters of defects constitute the major objectives of the researches for the future.