Exploiting continuous scanning laser Doppler vibrometry (CSLDV) in time domain correlation methods for noise source identification

This paper proposes the use of continuous scanning laser Doppler vibrometry (CSLDV) in
time domain correlation techniques that aim at characterizing the structure-borne contributions
of the noise emission of a mechanical system. The time domain correlation technique
presented in this paper is based on the use of FIR (finite impulse response) filters obtained
from the vibro-acoustic transfer matrix when vibration data are collected by laser Doppler
vibrometry (LDV) exploited in continuous scan mode (CSLDV). The advantages, especially in
terms of source decorrelation capabilities, related to the use of CSLDV for such purpose, with
respect to standard discrete scan (SLDV), are discussed throughout the paper. To validate this
approach, vibro-acoustic measurements were performed on a planetary gear motor for home
appliances. The analysis of results is also supported by a simulation.