OPTIMISATION AND USE OF A DIGITAL SPECKLE RADIOGRAPHY ALGORITHM FOR INVESTIGATION OF LONG ROD PENETRATION OF GRANULAR MEDIA.

Digital Speckle Radiography (DSR) is a technique allowing full field displacement maps in a plan within an opaque material to be determined. The displacements are determined by tracking the motions of small sub-sections of a deforming speckle pattern, produced by seeding an internal layer of lead and taking flash x-ray images. An improved DSR algorithm is discussed which can improve the often poor contrast in DSR images, such that the mean and variance of the speckle pattern is uniform. This considerably improves the correlation success relative to other similar algorithms for DSR experiments. A series of experiments involving the penetration of granular media by long-rod projectiles, and the improved correlation achieved using this new algorithm, are discussed. [ABSTRACT FROM AUTHOR]