Experimental Mechanics

, Volume 12, Issue 12, pp 543–548 | Cite as

An error analysis of holographic strains determined by cubic splines

The errors are analyzed which arise when computer-simulated holographic data of a loaded cantilever beam are interpolated and differentiated via cubic splines to yield strains and bending moments
  • L. H. Taylor
  • G. B. Brandt
Article

Abstract

Holographic measurements of an idealized cantilever beam under end-loading and uniform-loading conditions are simulated on a computer. Cubic splines are fitted to the simulated data and then used to evaluate the shear strain and bending moment. Controlled data errors are introduced into the simulated measurements and the strain and bending-moment results are compared with the known analytic results. When the data are not resolution limited, the accuracy of the results increases as more cubic splines are taken. However, when the data are resolution limited, the accuracy of the results is a maximum for an optimum number of cubic splines and the use of more splines actually decreases the accuracy.

Keywords

Mechanical Engineer Fluid Dynamics Simulated Data Shear Strain Error Analysis 

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Copyright information

© Society for Experimental Mechanics, Inc. 1972

Authors and Affiliations

  • L. H. Taylor
    • 1
  • G. B. Brandt
    • 1
  1. 1.Westinghouse Research LaboratoriesPittsburgh

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