The influence of selected operating parameters of a field sprayer on boom stability

During the application of plant protection products (PPP), the segments of a field sprayer's boom can be displaced from equilibrium, which can lead to uneven delivery of the sprayed liquid. Modern field sprayers are equipped with stabilization systems to eliminate this problem. However, these systems do not always operate correctly in all phases of a field sprayer's motion. Therefore, the aim of this study was to determine the influence of the speed at which a field sprayer crosses an obstacle on the displacement of the boom's terminal segments and the time after which the boom is stabilized. The experimental setup involved a field sprayer unit composed of a Claas AXOS 330 tractor and a mobile test bench - a detachable field sprayer with an air-assisted system and a boom with a working width of 21 m, which was equipped with a system for measuring boom displacement from equilibrium in two perpendicular planes. The boom's stability states were analyzed with the use of a fuzzy logic model developed by the authors. The measurements were performed in an experimental track with an obstacle. The displacement of boom tips in the horizontal and the vertical plane was registered during the experiment to determine boom stability. The experiment revealed that boom tips were displaced from equilibrium not only when the sprayer crossed the obstacle, but also when the tractor's front and rear wheels came into contact with the obstacle. Boom displacement was much greater in the horizontal than the vertical plane, and boom stabilization time was approximately three times longer in the horizontal than the vertical plane. The activation or deactivation of the air-assisted system had no significant effect on boom stability, but an increase in the sprayer's speed (from 4 to 12 km h-1) increased the time of unstable boom operation by around 50 %, decreased the time of semi-stable boom operation by around 34 %, and decreased boom stabilization time by around 45 %.