Measurement of the motion of fertilizer particles leaving a centrifugal spreader using a fast imaging system

Abstract

[Departement_IRSTEA]GEAPA [TR1_IRSTEA]41 - PRECITECH / PICOLOInternational audienceAlthough mechanically simple, centrifugal spreaders used for meneral fertilization involve complex physics that cannot be fully characterized at the present time. We are developing sensors to evaluate the spatial distribution of the fertilizer on the ground based on the measurement of initial flight conditions of fertilizer granules after their ejection by the spreading disk. The techniques developed are based on the analysis of images of the area around the disk showing the granule ejection. A high resolution - low cost imaging system for the analysis of high speed particle projection developed for this specific purpose is presented in this paper. The system, based ona camera and a sequence of flashes, is used to characterize the centrifugal speading of fertilizer particles ejected at speeds of approximately 30 ms-1. It automatically computes the direction of ejection and velocity of each granule observed in the image. Multi-exposure images collected with the camera installez perpendicular to the output flow of granules are analyzed to estimate the trajectories of fertilizer granules, using different motion estimation methods