Uncertainty of coordinate measurement of geometrical deviations

At University of Bielsko-Biala, simplified models for the coordinate measurement of different geometrical characteristics (size, distance, angle and geometrical deviations) have been developed. The most important assumption for measurement model is taking into account the obvious fact that coordinate measurement is indirect measurement. To develop the models of different geometrical characteristics the mathematical minimum number of required points was assumed. Models use information on CMM accuracy only in the form of formula for maximum permissible error of length measurement EL,MPE verified by actual acceptance or reverification test results. The presented uncertainty budgets enable analysis of influence of measurement uncertainty of particular coordinates’ differences on the total measurement uncertainty.