Measurement of random and transient deformations of a vibrating plate with multipulse digital holography and their decomposition into eigenmodes

Philipp Froening; Giancarlo Pedrini; H. Fessler; Hans J. Tiziani

doi:10.1117/12.307690

1 June 1998 Measurement of random and transient deformations of a vibrating plate with multipulse digital holography and their decomposition into eigenmodes

Philipp Froening, Giancarlo Pedrini, H. Fessler, Hans J. Tiziani

Author Affiliations +

Proceedings Volume 3411, Third International Conference on Vibration Measurements by Laser Techniques: Advances and Applications; (1998) https://doi.org/10.1117/12.307690
Event: Third International Conference on Vibration Measurements by Laser Techniques: Advances and Applications, 1998, Ancona, Italy

Abstract

A rectangular metal plate is randomly excited by a shaker or by the impact of a small rod. To investigate the temporal development of the induced deformation, an optical measuring system for the evaluation of transient deformations is used. A ruby laser, which is able to produce four laser pulses within a few laser pulses within a few microseconds and a setup of three CCD-cameras for recording the four pulses/interferograms were used. The images of the recorded holographic interference patterns are captured digitally with a framegrabber inside a PC. The reconstruction of the holograms is performed also digitally in the computer. For the later is obtained from the complex amplitude and the deformation between two laser pulses is calculated from phase subtraction and phase unwrapping of these two holograms. Each deformation image can be decomposed into the eigenmodes of the plate, which have to be known/measured before. By measurement of four holograms with a known pulses separation one is able to determine the deformation states between each adjacent pulse and at least the temporal development of the deformation and contributing magnitude coefficients of the eigenmodes.

Citation Download Citation

Philipp Froening, Giancarlo Pedrini, H. Fessler, and Hans J. Tiziani "Measurement of random and transient deformations of a vibrating plate with multipulse digital holography and their decomposition into eigenmodes", Proc. SPIE 3411, Third International Conference on Vibration Measurements by Laser Techniques: Advances and Applications, (1 June 1998); https://doi.org/10.1117/12.307690

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available