Development of working mode for an agricultural tractor during baler operation

Generally, performance evaluation of a tractor was conducted through field experiment. But, load of tractor during field experiment represents irregular fluctuation patterns. To evaluate the performance of a tractor reflecting load fluctuations, a development of a working mode of a standardized tractor is needed. The purpose of this study was to analyze load using measured by field experiments and to develop the working mode for baler operation. A load measurement system was constructed with strain-gages to measure torques of transmission and PTO input shafts, pressure sensors to measure pressure of hydraulic pumps, I/O interface to acquire the sensor signals, and an embedded system to determine power requirements. In order to collect the load data according to the baler operation, the field experiment was conducted at transmission gear of L3 and PTO gear of P1 on a field. The working mode according to the baler operation was developed using development method of the driving cycle. The results showed that the load for the tractor increased for bail formation in the bailing period, decreased by stopping of tractor in the tying a bale period, and increased for release of the bail in the discharging period. The average torque during baler operation was about 200 Nm, which is about 50% of the maximum engine torque. The developed working mode was verified by comparing with the international driving cycle. The working mode was satisfied with the all criteria assessments. Therefore, it is determined that the developed working mode is applicable to the tractor.