A novel method of evaluating dynamic measurement uncertainty utilizing digital filters

Abstract

For every measurement, a measurement uncertainty should be associated with the estimate of the measurand. In particular, this applies to all the common non-stationary transient dynamic measurements made with linear time-invariant measurement systems, despite the present standard treatment providing little guidance for this case. To complete recent studies on the estimation and correction of the systematic dynamic error, the remaining evaluation of measurement uncertainty is addressed here. A method based on digital filtering will be utilized to find the generically time-dependent dynamic contribution to the uncertainty. It will be shown that the widely accepted approach to calculate the stationary uncertainty can be extended to transient measurements, provided some complementary techniques are used and the sensitivity is generalized to be a time-dependent signal instead of a constant. For illustration, the method is applied to the same measurement system analysed in the related published studies.