Servizio Comunitario di Informazione in materia di Ricerca e Sviluppo - CORDIS

OLGA: size distribution analyzer on moving conveyor belts

The OLGA size distribution analyzer consists of a matrix DTC camera (512 x 512 pixels) positioned above the conveyor. The camera selected has a short integration time to prevent any blur due to the motion of the materials, and it transmits the image to a processing unit. A tunnel is used to prevent any external light disturbances. The selected image processing unit is the EDIXIA IA 1000 model. The results are displayed on a video console.

The processing algorithm consists of 2 separate sections: preprocessing designed to improve the image characteristics; and processing allowing for extraction of significant parameters and based on the mathematical morphology of grey levels.

The analyzer performances may be summarized as follows:
repeatability: different analyzes performed on a single image provide identical results;
precision: several analyzes performed on a single sample resulted in an absolute scattering of approximately 3 units in terms of percentage in the various categories;
sensitivity: the analyzer detects variations of 5% in aggregate size;
measuring range: the analyzer measures aggregate sizes ranging from D to d, with D = size of coarsed grains, and d = max (D/15, 2 mm).


Jean Michel ARNAUD, (Directeur Adjoint)
Tel.: +33-40-375137
Fax: +33-40-370335