Fill volume in a storage vessel determined by optical scanning

Measurement of fill volume of granular materials in closed vessels or in hoppers is challenging and often not amenable to direct determination by weighing or to indirect determination from a point measurement of fill height. This paper demonstrates the use off-the-shelf optical 3D scanners integrated into the cover plate of a vessel containing bulk solids, for fill volume determination and measurement of discharge rate in real time. A model suitable for vessels of different scale and shape, the Optical Fill Volume (OFV), has been developed to process scan data. Experimental tests were carried out using polyethylene pellets, agricultural lime and mustard seeds in 50 and 200-l vessels. Accuracy was within 1% of the vessel capacity with a measurement rate up to 5 Hz.