In tolerancing analysis, geometrical or contact specifications can be represented by polytopes. Due to the degrees of invariance of surfaces and that of freedom of joints, these operand polytopes are originally unbounded in most of the cases (i.e. polyhedra). Homri et al. proposed the introduction of virtual boundaries (called cap half-spaces) over the unbounded displacements of each polyhedron...

A computer aided tolerancing tool is presented that assists the designer in functional tolerance specification. The theoretical concepts for subsequent tolerance analysis are also provided. The computer aided tolerancing tool is part of a feature based object oriented (re)–design support system, called FROOM. FROOM’s assembly modelling capabilities provide basic information for functional toler...

The tolerancing process links the virtual and the real worlds. From the former, tolerances define a variational geometrical language (geometric parameters). From the latter, there are values limiting those parameters. The beginning of a tolerancing process is in this duality. As high precisions assemblies cannot be analyzed with the assumption that form errors are negligible, we propose to appl...

We propose to use a knowledge based approach to assist in mechanical design focusing on dimensional tolerancing. To illustrate our approach, we capture the knowledge which human designers utilize in order to specify dimensional tolerances on shafts and mating holes in order to meet desired classes of fit as set by relevant engineering standards. The software system we developed would help mecha...