Papers by Author: L. Blunt

Abstract: This paper presents a methodology for validating surface metrology software. Based uncertainty analysis, a set of reference data sets with mathematical correct results, call the type F1 softgauges, have been developed. Special designed profiles can be used to check specification uncertainty and algebra calculation is used to lower method uncertainty. The results shown that specification uncertainties were main uncertainty contributors.

Abstract: The detection of stationary and non-stationary noise in environmental vibration data is an important issue when considering the precision of the Watt balance, an electromechanical apparatus for the new definition of the kilogram in the international system of Units (SI). In this paper, the authors propose a frequency histogram method to find the structure of the stationary noise from large amount of datasets. For the non-stationary noise, the authors propose a wavelet based denoising methods to distinguish the transient events from the background “noise”, to find their duration and content and to identify their location in time.

Abstract: A basic analytical model of the out-pump type complex journal gas bearing is set up to investigate the coupling mechanism between aerodynamics and aerostatics in a complex gas bearing and to improve its performance, under incompressible conditions. The analytical model shows that the load-carrying capacity function is composed of five items. Apparently, there is both pressure and structure coupling between aerodynamics and aerostatics; identically, the surface feature function is positive; and when the groove distribution coefficient is 0.30, it is approximately maximum.

Abstract: This paper provides an overview of advances in the surface metrology field, concerning surface creation, measurement need, instrumentation, characterisation methods and standard development. It indicates industry requirements and further developments for micro and nano scalar surface metrology.