GEOMETRIC DIMENSIONING, TOLERANCING AND INSPECTION

Any industrial product, regarded as a part assembly, shows differences from the ideal dimensions and/or geometry, defined by the CAD geometric model, due to the manufacturing processes.

The design activity is therefore incomplete until the Technical Product Documentation (TPD) includes the indication of the admissible deviations, in terms of dimensional, macro and micro geometric tolerances, which allow to satisfy the functional and safety, performance, cost, reliability, etc. requirements.

The Geometrical Product Specification (ISO GPS) or the Geometric Dimensioning and Tolerancing (ASME GD&T), two dialects of the same language, allow to indicate the hierarchical relationships, the functional requirements and the tolerances of the single features present in the various parts of the product/assembly in TPD, i.e. both in 2D drawings and in 3D CAD models and in Digital Twin using Model Based Definition (MBD) tools.

The research activity in this field concerns not only the ISO and ASME standard evolution, but also the development of methodologies and tools, often integrated in CAD environments, for the geometric specification, analysis and synthesis of tolerance stack-ups (CA Tolerancing - CAT), the analysis of the costs associated with the tolerancing schemes adopted (CA Costing), the inspection and verification of conformity of parts, including the evaluation of the performances of innovative measuring and 3D scanning systems.

Keywords:
Geometrical Product Specification (ISO GPS); Geometric Dimensioning and Tolerancing (ASME GD&T); Model Based Definition (MBD); Digital Twin; Inspection methods; Tolerance Stack-up Analysis and Synthesis.

ERC Keywords:

• PE8_7 Mechanical and manufacturing engineering (shaping, mounting, joining, separation).