Combined digital-DOE holographic interferometer for force identification in vibroacoustics
Résumé
This paper presents the proof of principle of high-speed holographic measurements applied to solve an inverse problem in the domain of vibroacoustics. In order to get a robust and efficient set-up, a compact holographic interferometer which includes a Fresnel configuration equipped with a negative zoom for large surfaces and a diffractive optical element to improve the photometric efficiency of the set-up was developed. The vibration measurements from the digital holographic set-up are applied to the “RIFF” method which provides identification of the force distribution at the surface of the vibrating object, by solving a regularized inverse problem. Experimental results demonstrate the advantage provided by full-field measurements from multi-point holographic vibrometer with fine spatial and temporal resolutions.