An assessment of gauge repeatability and reproducibility with multiple characteristics

Measurement system analysis plays an important role of many continuous improvement initiatives in the manufacturing industry. Measurement systems are commonly evaluated by performing a gauge repeatability and reproducibility (GRR) study. In some circumstances, manufacturing tests in a GRR study may have multiple characteristics with a multivariate normal distribution. To determine the preferred method for a GRR analysis, multivariate analysis of variance (MANOVA) and principal component analysis (PCA) are applied to data taken from two real cases. Three performance measures [precision to tolerance ratio (PTRM), the percentage of repeatability and reproducibility (%RRM), and signal-tonoise ratio (SNRM)] are used to evaluate the adequacy of the measurement process. The results show that the MANOVA method is suitable for a GRR study with multiple characteristics. Copyright by ASTM Int'l (all rights reserved).