Uncertainty Tool For Large Data Acquisition System

Abstract

This paper introduces an uncertainty model and analyzer tool being developed for one of the world’s largest space environmental test facilities—the Spacecraft Propulsion Research Facility (B•2) located at NASA Glenn Research Center’s Plum Brook Station near Sandusky, Ohio. The B•2 is the world’s only facility capable of testing full-scale upper-stage launch vehicles and rocket engines under simulated high-altitude conditions (NASA Glenn Research Center, Spacecraft Propulsion Research Facility (B•2), http://facilities.grc.nasa.gov/b2/ Accessed Jan. 22, 2014). Developing an uncertainty tool for the data acquisition of a test facility of this scale presents unique metrology challenges. Not only must the uncertainty analyzer tool be versatile enough to accommodate a wide range of disciplines and measurement requirements (such as temperature, pressure, strain, vacuum, and acceleration), but it must provide a user-interactive platform for evaluating system measurement uncertainty based on customer-chosen measurement scenarios ranging from the most simplistic tests to the most complex ones. The uncertainty analyzer tool, which was developed in Microsoft’s Visual Basic for Applications (VBA) in Excel, will serve multiple purposes, including aiding in the optimal selection of measuring and test equipment, communicating capabilities to customers, and supporting all decisions based on measurements. This paper outlines the methodology followed, the features of this tool, and how the tool can be applied to the measurement processes of different facilities.