The Projected Pattern Correlation Technique for Vibration Measurements

Abstract

The objective of this paper is the description of the Projected Pattern Correlation method for measuring surface velocities and to present results of a feasibility study. Similar to the Moiré technique the local surface velocities of a large area are determined simultaneously, which replace a time consuming point wise scanning as it is necessary in e.g. Laser Doppler Vibrometry. Furthermore, the dynamics of non-periodic processes can be resolved temporally and spatially. In difference to the Moiré or grid projection techniques the evaluation step is fast (real-time measurements are possible) more robust and provides a high spatial resolution. The measurement precision is assessed using a simple test arrangement. Vibration measurements are performed on a satellite model structure and a honeycomb sandwich plate.