Banco prova di rilevatori di resa per mietitrebbiatrici

Electronic devices allow to check and improve the quality level of many harvesting operations, included the instantaneous monitoring of the grain yield and loss. The modern combine harvesters are equipped with several different yield sensor types, measuring parameters that can be directly (i.e. grain mass, or weight) or indirectly (i.e. variation of a magnetic field) related to the yield flow rate. The ITAF Department of the University of Palermo and the Institute of Agricultural Engineering of the Universiy of Milan jointly designed and manufactured a test bench in order to ascertain the precision, the reliability and the calibration ability of the various yield monitoring systems, to be checked above all in critical working conditions, such as quick flow rate variations, working on slopes, rotation speed surging of the screw feeder, etc. Thanks to the gravity, a suitable grain amount flows from a tank through an adjustable port (varying its section between 0 and 65 cm²), to obtain a constant flow that can be varied within wide limits (0-16 t/h); the grain is then pushed into the elevator-screw device, where the yield sensor(s) are fitted.