A Multi-stage Evolutionary Tomographic Reconstruction Algorithm Using Ultrasound Time-of-Flight Projections

Various tomographic reconstruction algorithms are introduced, for testing engineering materials in a non-destructive manner. Majority of the genetic algorithms utilized in reconstruction methods are based on the principles of binary-coded genetic algorithms. These algorithms solve the reconstruction problems using a single-stage strategy. They start with initial solutions of the resolution, same as that of the final desired resolution of reconstructed solution. This article focuses on the improvised evolutionary tomographic reconstruction procedure, which is designed on the principles of real-coded genetic algorithms. A multi-stage strategy is proposed for solving the reconstruction problem, and the pseudo-code outlining the significant hierarchical steps in the multi-step real-coded genetic algorithm reconstruction approach is presented and implemented. The reconstruction algorithm starts initially with randomly initialized solution guesses of lower resolution, which evolve at intermediate stages towards finally yielding solutions of required resolution. Efficacy of the proposed methodology is demonstrated, through several simulations using ultrasound time-of-flight projection data.