The application of evolutionary and maximum entropy algorithms to photoelastic spectral analysis

Over the past 10 years, spectral analysis has been shown to have the potential to be a reliable means of automating photoelasticity. However, the four methods of analyzing the spectra that have previously been proposed are slow and, in some cases, inaccurate. This paper describes three new methods for spectral analysis based on the maximum entropy method, a genetic algorithm and a memetic algorithm. Thirty-five spectra for known fringe orders were recorded and used in testing the four existing methods and the three new ones. It was found that the new methods were all considerably faster than the existing methods, although less accurate than the best existing method. By combining the maximum entropy method with either the genetic algorithm or the memetic algorithm, spectra could be analyzed up to 30 times as fast as they could with any of the existing methods and with comparable accuracy.