Investigation of the effect of temperature and other significant factors on systematic error and measurement uncertainty in CMM measurements by applying design of experiments

Abstract

The design of experiments was used in this paper in order to determine the significance of particular factors for the parameters that indicate the quality of measurement results obtained by means of a coordinate measuring machine (CMM). Special emphasis was placed on the interaction of temperature and other factors. In accordance with the design of experiments, the diameter and roundness of a ring gauge were measured at the reference temperature and at the temperature of 26 °C. The ISO 15530-3:2011 standard for the assessment of measurement uncertainty of CMM measurements distinguishes systematic error from measurement uncertainty. Thus, separate analyses were done on how temperature, in the first place, but also workpiece position on the CMM table, coordinate system, stylus tip diameter, sampling size and interaction of temperature with other factors affect systematic error and measurement uncertainty. The experimental results showed an increase in systematic error at the higher temperature when the diameter was measured, whereas with roundness, systematic error was even smaller at the higher temperature. As for measurement uncertainty, measurements made at the higher temperature have a significantly greater uncertainty when the diameter is measured, unlike with roundness, where the effect of temperature is almost negligible.