Fast imaging system for fertiliser granule motion: a way for centrifugal spreading management

Abstract

Mineral fertilization by centrifugal spreading is a high polluting process. Since few years, a lot of research have been realized to reduce impacts on environment. For that, centrifugal spreading, and particularly the initial conditions of flight of the granules, have to be very accurately determined and understood. This paper describes the conception of a fast imaging system for the characterization of the fertilizer centrifugal spreading in laboratory. This multiexposure patented system allows to determine the granule trajectories after their ejection, by using a high resolution low cost digital camera combined to a set of flashes, and also different motion estimation methods. The use of a combination between Markov random fields method and a theoretical modelling of the shape of the throws gives very satisfying results, which can be then used in ballistic flight model to predict fertilizer distribution on the ground. This repartition must be compared to a real repartition obtained during spreading hall tests. Prospective are numerous in term of use of our patented system. ENGRAIS, IMAGERIE, CONTROLE, EPANDAGE, DISTRIBUTEUR, CENTRIFUGATION, FERTILISATION MINERALE, DIRECTION, CAMERA, LIMITE DE RESOLUTION SPATIALE, METHODE, JET, ENGRAIS, DISTRIBUTEUR D'ENGRAIS