This study was conducted to analyze effects of the gear
selection on load acting on the transmission and PTO input shafts
of a 75 kW agricultural tractor during rotary tillage. First, the loads
acting on the transmission and PTO input shafts were measured
during rotary tillage. Rotary tillage was conducted at three ground
speeds and three PTO rotational speeds under upland field sites
with the same soil conditions. Second, loads on the transmission
and PTO input shafts were evaluated. The results showed that the
average torque on the transmission input shaft increased
significantly as the ground speed increased from L1 to L3 at the
same PTO rotational speed. Also, the average torque on the PTO
input shaft increased as the PTO rotational speed increased at the
same ground speed