Discrete Digital Projections Correlation: A Reconstruction-Free Method to Quantify Local Kinematics in Granular Media by X-ray Tomography

We propose a new method to measure the translations and rotations of each individual grain in a granular material imaged by computerized tomography. Unlike the classic approach, which requires that both initial and current configurations be fully reconstructed, ours only requires a reconstruction of the initial configuration. In this sense, our method is reconstruction-free, since any subsequent deformed state can be analyzed without further reconstruction. One distinguishing feature of the proposed method is that it requires very few projections of the deformed sample, thus allowing for time-resolved experiments.