Experimental Mechanics

, Volume 11, Issue 4, pp 296–302 | Cite as

Deflection measurements using moiré gap effect

A generalized moiré gap equation and its application to the measurement of deflection of structures are presented in this paper
  • F. P. Chiang
  • B. Ranganayakamma


The moiré gap equation originally derived by Sciammarella and Chiang has been generalized to include linear and rotational mismatches. The equation is then applied to the measurement of deflection of beams and plates. The method has the advantages of being simple in comparison with other optical whole-field methods. The application of moiré gap effect to the study of dynamic problems is also discussed.


Mechanical Engineer Fluid Dynamics Dynamic Problem Deflection Measurement Rotational Mismatch 
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Copyright information

© Society for Experimental Mechanics, Inc. 1971

Authors and Affiliations

  • F. P. Chiang
    • 1
  • B. Ranganayakamma
    • 1
  1. 1.Department of Mechanics, College of EngineeringState University of New York at Stony BrookLong Island

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