Phase Unwrapping by a Regularization Technique in Fracture Measuring Using ESPI

Abstract

Detection and measurement of superficial fractures at engineeringstructures by means of ESPI techniques are very well known. However,several problems that still persist are the fracture detection onsurfaces of irregular shape, or when the specimen is discontinuous.In this case the fringe analysis becomes very difficult and in occasionswithout solution, particularly in the process of phase unwrapping.In this work, experimental results are presented obtained by meansof ESPI for the detection and measurement of fractures on a surface.Regularization techniques are used to obtain wrapped and to unwrapthe phase of discontinuous specimens. Results are shown for severaltypes of deformed objects with mechanical and thermal loads.