ISSN: 1945-7553
CODEN: JTEVAB
Published Online: 6 August 2010
Page Count: 9

Determining the Slope and Quality of Fit for the Linear Part of a Test Record

Graham, Stephen M.
Mechanical Engineering Department, United States Naval Academy, Annapolis, MD

Adler, Matthew A.
Jacobs ESTS Group/ICRC, Marshall Space Flight Center, Huntsville, AL

(Received 12 February 2010; accepted 5 July 2010)

Abstract

It is often necessary to determine the slope of a linear region within a test record, and for standardization purposes, it is desirable to have a method for determining the slope that is not subjective. A fully automated algorithm is presented, which is independent of operator judgment for data sets that meet specific quality of data and fit criteria. The algorithm uses analysis of residuals to simulate the visual process of determining the linear region. Analysis of benchmark and real test data provide validation that the algorithm correctly differentiates between problem data (noisy, insufficient digital resolution, or no significant linear range) and good data.

Keywords:
linear regression, mechanical testing, analysis of residuals

Paper ID: JTE103038
DOI: 10.1520/JTE103038
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