A new approach for determining the particle size distribution of muck piles is presented. It utilizes images from drones and a combined 3D-2D approach for particle delineation and sizing. The 3D part uses shape analysis to identify particles and applies 2D image analysis to support the delineation. The procedure is less prone to ambiguities related to shadows, rock structure, or different light conditions which is mainly the reason for erroneous particle delineations in pure 2D. And it inherently scales correctly. The approach analyzes the entire muck pile area in a single run delivering hundreds of thousands of individual measurements which leads to statistically very strong results that are highly robust against single mismeasurements, if any. The new fragmentation analysis method has been audited by comparison against known data from sieving in lab scale. It has been applied at several quarries, under different light situations, and even underground. The delivered results showed to be reasonable in all cases. Like any other remote sensing approach, the method analyzes the top layer of the muck pile only. However, as it considers the entire surface and does the job fully automatic without extensive post processing, it is an economic approach for an objective quantification and assessment of the blasting work.
