Interlaboratory Empirical Reproducibility Study Based on a GD&T Benchmark

Abstract

<jats:p>The ASME Y14.5 geometric dimensioning and tolerancing (GD&amp;T) and ISO-GPS (geometrical product specifications) standards define tolerances that can be added to components to achieve the necessary functionality and performance. The zone that each feature must lie within is defined in each tolerance. Measurement processes, including planning, programming, data collection (with contact or without contact), and data processing, check the compliance of the part with these specifications (tolerances). Over the last two decades, many works have been realized by the metrology community to investigate the accuracy, the measuring methods, and, specifically, the measurement errors of fixed and portable coordinate measuring machines (CMMs). A review of the literature showed the progression of CMMs in terms of accuracy and repeatability. However, discrepancies were observed between measurements using different CMMs or operators. This paper proposed a GD&amp;T-based benchmark for the evaluation of the performance of different CMM operators in computer-aided inspection (CAI), considering different criteria related to the dimensional and geometrical features. An artifact was designed using basic geometries (cylinder and plane) and free-form surfaces. The results obtained from the interlaboratory comparison study showed significant performance variability for complex GD&amp;T, such as in the composite profile and localization. This, in turn, emphasized the importance of GD&amp;T training and certification in order to ensure a uniform understanding among different operators, combined with a fully automated inspection code generator for GD&amp;T purposes.</jats:p>

Statistical Tolerance Analysis—A Survey on Awareness, Use and Need in German Industry

“…on the functionality and aesthetic quality of a product has not yet been internalized everywhere. One participant highlighted the importance of the "creation of a uniform understanding" for the company's success, which is also considered essential among researchers [44,63]. This becomes even more obvious when analyzing the results in Figure 7b, which ranks the aspects that respondents would consider if the scrap rate during production were to exceed its given limit.…”

Special Issue on Manufacturing Metrology

“…Two papers were related to laboratory metrology systems. A GD&T-based benchmark for evaluating the performance of different CMM operators in computer-aided inspection (CAI) was proposed [24]. This, in turn, emphasized the importance of GD&T training and certification in order to ensure a uniform understanding among different operators, combined with a fully automated inspection code generator for GD&T purposes.…”