Equivalence of Intensity Integration Technique with Line Summation method for contouring of 1D Reflective surfaces

Raghuraman M, SRM University

Correlation, IIT, optical strain, deformation, line, summation, slope, curvature, reflective

Digital image correlation and tracking (DIC) is an optical method that employs tracking and image registration techniques for accurate 2D and 3D measurements of changes in images. This is often used to measure deformation, displacement, strain. Intensity Integration Technique and Line summation method are one of DIC Techniques. The purpose of this research is to identify the similarities between the Intensity Integration Technique and Line Summation method for Cantilever beam under the given loading conditions where the slope and curvature is found out for mirror like reflective surfaces. In Intensity Integration Technique (IIT) for small deformation, it is assumed that total amount of light reflected by a designated area on the surface would be same before and after deformation when there is no change in illumination (conservation of the total quantity of reflected light). Line summation method is a grid method where the optical strain of grid lines is related to slope and curvature of the loaded beams (Theory of bending). The spacing between two grid lines is unaltered under no load condition and spacing changes when it is in loaded condition. Thus, the strain is related to slope and curvature. These findings may be useful in study of material deformation, nature of defect (inclusion and void) and crack propagation in real-world applications, as it has the potential to become a cheap, simple yet accurate solution.
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Paper ID: GRDCF002009
Published in: Conference : International Conference on Innovations in Engineering and Technology (ICIET - 2016)
Page(s): 18 - 23