LAUSR

Abstract. An experimental hydraulic drive was designed for a pull-type F41 Dion forage harvester to control and measure the rotational speed and applied load of feedrolls. Three types of sensors were placed on the experimental harvester: (1) four hydraulic pressure sensors to measure pressure in the input and output lines of the feedroll and header motors; (2) three integrated tachometers to measure motor speed, and (3) a potentiometer-based sensor to measure crop mass flow. Data was collected using a National Instruments USB 6216 TM device and LabView TM code. Pressure drop of the motor depended on mass flowrate of the crop material being conveyed. Power consumption increased with increasing rate of forage throughput. Increased forward speed decreased the specific energy requirements of the header and feedroll motors. The feedroll opening measurements using the potentiometer sensor were correlated with the experimental mass flowrate measured by weighing the forage wagon. Correlation coefficients were R 2 = 0.97 and R 2 = 0.59 at length of cut (LOC) of 15 and 9.5 mm, respectively. An analysis of variance indicated that both feedroll opening and throughput were affected by forward speed (p