Journal of Theoretical
and Applied Mechanics
50, 4, pp. 1049-1061, Warsaw 2012
An uncertainty propagation in developed vision based measurement system aided by numerical and experimental tests
In the paper, the vision-based method of static in-plane deflection measurement of a structure is presented. Displacements of measurement points of the structure under the load are computed by means of the normalized digital image correlation coefficient. The application of the homography transformation enables the deflection field to be computed from two images of the structure acquired from distinct points in space. The scale coefficient calculation and marker matching algorithms have been introduced in order to increase the level of automation of the method. The paper presents the results of numerical investigations of the uncertainty propagation in the proposed algorithms. The qualitative comparison of the numerical data and the results of the experiment have been shown.
Keywords: digital image correlation; homography mapping; vision system