Experimental Mechanics

, Volume 18, Issue 6, pp 221–226 | Cite as

On the interpretation of shadow-moiré fringes

Influences of rotations and translations of the grating on the sensitivity are presented, general expressions are given and simplified equations are obtained for practical cases
  • J. Buitrago
  • A. J. Durelli


Shadow moiré is presented as one of the methods used to determine loci of constant height in curved surfaces (isotathmics). A general expression to interpret the fringes is derived taking into consideration possible rotations and translation of the grating. A discussion of the influence of such rotations and translation on the sensitivity of the response is also presented. Furthermore, simplified equations are obtained for particular cases of practical interest. An example of application to the case of an inverted perforated tube is shown.


General Expression Mechanical Engineer Fluid Dynamics Curve Surface Practical Interest 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    Hovanesian, J.D., Haskell, R.E. and Powell, R.L., “Use of a Projected Ruling Moiré Method for Vibration and Deflection Measurement of Three-Dimensional Structures,” Proc. Engrg. Applications of Holography (Symp.), sponsored by ARPA, conducted by TRW Systems, Los Angeles (Feb. 16–18, 1972). Also, Hovanesian, J.D. and Hung, Y.Y., “Moiré Contour Sum, Contour Difference and Vibration Analysis of Arbitrary Objects,” Appl. Opt.,10,(12) (Dec. 1971).Google Scholar
  2. 2.
    Chiang, F.P. and Khetan, R.P., “A Moiré Method for Measuring Large Deflection of Shells,” State Univ. of NY at Stony Brook, College of Engrg. Rep. #221 (Feb. 1972). Paper presented at SESA Spring Meeting, 1972. (Research in Progress.) Google Scholar
  3. 3.
    Khetan, R.P., “Theory and Applications of Projection Moiré Methods,” PhD Dissertation, Dept. of Mechanics, State Univ. of NY at Stony Brook (May 1975).Google Scholar
  4. 4.
    Weller, R. and Shepard, M., “Displacement Measurements by Mechanical Interferometry,” Proc. SESA,VI (1), (1948).Google Scholar
  5. 5.
    Theocaris, P.S., Proc. Int. Symp. Shell Struct. (Warsaw 1963), North Holland Pub. Co., Amsterdam, 887 (1965).Google Scholar
  6. 6.
    Theocaris, P.S., “Isopachic Patterns by the Moiré Method,”Experimental Mechanics,4 (6),153–159 (Jun 1964).Google Scholar
  7. 7.
    Takasaki, H., “Moiré Topography,”Appl. Opt.,9, (6),1467–1472 (Jun. 1970).Google Scholar
  8. 8.
    Takasaki, H., “Moiré Topography,”Appl. Opt.,12 (2),845–850 (Apr. 1973).Google Scholar
  9. 9.
    Chiang, F.P., “A Shadow-moiré Method with Two Discrete Sensitivities,”Experimental Mechanics,15 (10)382–385 (Oct. 1975).Google Scholar
  10. 10.
    Marasco, J., “Use of a Curved Grating in Shadow Moiré,”Experimental Mechanics,15 (12),464–470 (Dec. 1975).Google Scholar
  11. 11.
    Meadows, D.M. andJohnson, W.D., “Generation of Surface Contours by Moiré Patterns,”Appl. Opt.,9 (4),942–947 (Apr. 1970).Google Scholar
  12. 12.
    Allen, J.B. andMeadows, D.M., “Removal of Unwanted Patterns from Moiré Contours Maps by Grid Translation Techniques,”Appl. Opt.,10 (1),210–212 (Jan. 1971).Google Scholar
  13. 13.
    Pirodda, L., “Principie Applicazioni di un Metodo Fotogrametrico Basado sull'Impiego Moiré,” Revista di Ingegneria, (12) (Dec. 1969). See also: Pirodda, L., “Optical Differentiation of Geometrical Patterns,” Experimental Mechanics,17 (11), 427–432 (Nov. 1977).Google Scholar
  14. 14.
    Durelli, A.J. and Parks, V.J., Moiré Analysis of Strain, McGraw-Hill, 66 (1970).Google Scholar

Copyright information

© Society for Experimental Mechanics, Inc. 1978

Authors and Affiliations

  • J. Buitrago
    • 1
  • A. J. Durelli
    • 2
  1. 1.Catholic UniversityWashington, DC
  2. 2.Oakland UniversityRochester

Personalised recommendations