Curvature Measurement of Thin Plates with the Help of Digital Image Processing

The verification of different plate bending problems require a punctual measurement method of the bent shape. However, with a proper curvature measurement procedure the calculations can be made more accurate. This is due to the workaround this method provides by neglecting the inaccuracies of the beam theory and the tensile tests, measuring directly the function between the curvature and bending moment for a given sheet metal. The measurements in this paper are made with the help of a digital camera and telephotographic lens. The evaluations of these images are compared to the results obtained from the Euler-Bernoulli beam theory. While the results regarding the curvature measurements have a significant deviation, the shape of the plate is in good agreement with the numerical calculations.