Photoelasticity Color Dynamics Dataset for stress analysis applications
Photoelasticity is an optical technique that takes advantage of birefringence in some materials to obtain isoclinic and isochromatic fringe patterns. Which represent the direction and the difference of the principal stresses in a sample under a mechanical load. The changes in the photoelasticity fringe patterns contain information about the stresses presented in a sample. One of the ways to access this information without unwrapping the fringe patterns is through pixel intensity values. Which allow to reconstruct temporary signals that represent the changes of stresses produced by external stimulations such as mechanical loads or temperature changes. Today there is no dataset in the literature that contains data abourt this type of information. To obtain this data set, sequences of 720 images of synthetic photoelasticity models with different geometries were generated and a progressive mechanical load between 0 and 4000 Newtons was applied. The data set presented below contains two arrays called testing and training which have the following dimensions [8000,2161] and [32000,2161], respectively. The rows represent the number of pixels from which information was obteined and the columns are divided into 4 sections. The columns between 1 and 720 correspond to the RED channel, the columns between 721 and 1440 correspond to the GREEN channel and data in columns 1441 and 2160 correspond to the BLUE channel. Finally, the data in column 2161 corresponds to the classification of each pixel. The classification is divided into 4 labels. Number 1 corresponds to pixels located in high stress zone, number 2 corresponds to pixels located in a medium stress zone, number 3 corresponds to pixels located in low stress zone, and number 4 corresponds to pixels located in a zone with the presence of residual stresses. The stress classification criterion was based on the fringe order, orders greater than 6.5 were taken as high stresses, between 2 and 6.5 as medium stresses, and below 2 orders were considered as low stresses. The category of residual stresses was taken based on a geometric selection of an area with the presence of residual stresses.