Automatic vibration mode tracking using a scanning laser Doppler vibrometer

Optical measurement techniques are being used more and more for quality
control in the production process. An important problem when trying to
implement optical measurement systems, and in particular the scanning
laser Doppler vibrometer (SLDV) which is considered in this paper, is
that user interaction is always required. The need for user interaction
implies an increase in testing time and cost and also brings an
additional source of variability of the test results. In this article,
a completely autonomous test procedure is developed to track the
vibration behavior of a product during the production process (this
includes automatic laser focussing, position calibration, object
recognition, grid generation and mode estimation). The proposed
procedure typically requires a few minutes only to automatically
determine a high-resolution model of the vibration behavior. The method
will be validated on measurements of an electronic circuit board. (C)
2003 Elsevier Ltd. All rights reserved.