Department of Agricultural Engineering, Faculty of Agriculture, Trakia University, 6000 Stara Zagora, Bulgaria
(Manuscript received 12 December 2020; accepted for publication 2 April 2021)
Abstract. The article studied the effect of transport vehicles on the grain harvester idle time during wheat, barley and rapeseed harvesting in 6 agricultural farms. In each of the farms one grain harvester and the established harvesting organization were studied without changing the unloading mode and the specific activities performed by the harvester operators and transportation vehicles. By multifactor regression analysis the effect of time for moving the transport vehicle on the grain harvester idle time was established. In addition, the value of the determination coefficient R2=0.54 reveals that 54% of the harvester idle time for unloading the grain hopper (Т1) change is due to the change of significant times and 46% to the effect of unmanageable factors. It has been established that the change in the time from opening the unloading auger to its activation depends on the position of transport vehicles on the field (t1) and the time for their movement to the harvester auger (t2). The results obtained can be used to minimize costs in the technological process of crop harvesting.