TITLE

Strain, curvature, and twist measurements in digital holographic interferometry using pseudo-Wigner–Ville distribution based method

AUTHOR(S)
Rajshekhar, G.; Gorthi, Sai Siva; Rastogi, Pramod
PUB. DATE
September 2009
SOURCE
Review of Scientific Instruments;Sep2009, Vol. 80 Issue 9, p093107
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
Measurement of strain, curvature, and twist of a deformed object play an important role in deformation analysis. Strain depends on the first order displacement derivative, whereas curvature and twist are determined by second order displacement derivatives. This paper proposes a pseudo-Wigner–Ville distribution based method for measurement of strain, curvature, and twist in digital holographic interferometry where the object deformation or displacement is encoded as interference phase. In the proposed method, the phase derivative is estimated by peak detection of pseudo-Wigner–Ville distribution evaluated along each row/column of the reconstructed interference field. A complex exponential signal with unit amplitude and the phase derivative estimate as the argument is then generated and the pseudo-Wigner–Ville distribution along each row/column of this signal is evaluated. The curvature is estimated by using peak tracking strategy for the new distribution. For estimation of twist, the pseudo-Wigner–Ville distribution is evaluated along each column/row (i.e., in alternate direction with respect to the previous one) for the generated complex exponential signal and the corresponding peak detection gives the twist estimate.
ACCESSION #
44388132

 

Share

Read the Article

Courtesy of THE LIBRARY OF VIRGINIA

Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics