Sirvi Autor "Ihnatiev, Yevhen" järgi
Nüüd näidatakse 1 - 7 7
Tulemused lehekülje kohta
Sorteerimisvalikud
Kirje Agrophysical condition of chernozem as a criterion for its readiness for soil tillage minimization(Estonian University of Life Sciences, 2025) Ihnatiev, Yevhen; Bulgakov, V.; Demydenko, O.; Holovach, I.; Trokhaniak, O.; Rucins, A.; Olt, Jüri; Estonian University of Life Sciences. Institute of Forestry and EngineeringThe objective of this study was to develop an agrophysical criterion for assessing the condition of leached chernozem under systematic shallow tillage for six years, using differential porosity, crop productivity, and energy efficiency as indicators. The results were compared to those obtained under conventional ploughing, with the goal of evaluating the feasibility of further tillage minimization in a short-rotation grain crop rotation system. The study employed standard research methods, including field observations, laboratory analysis, mathematical statistics, and comparative-calculative approaches. Under shallow tillage, the median bulk density in the 0–30 cm soil layer was higher by 0.03 g cm–3 compared to ploughing, while the standardized density range remained similar across tillage systems. However, both the upper and lower typical values increased by 0.02 g cm–3 under shallow tillage. The coefficient of variation for bulk density was 1.85 times higher under ploughing than under shallow tillage. Differential porosity measurements across five crops in the sixth year of the trial revealed that in spring, shallow tillage resulted in higher bulk density (by 0.06 g cm–3), lower total porosity (by 3%), and a 6.0% reduction in air-filled pore volume compared to ploughing. At the same time, the ratio of waterfilled to air-filled pores approached an optimal 1:1 balance under shallow tillage, whereas ploughed soils showed a dominance of air-filled pores. Systematic use of both ploughing and conservation-oriented shallow tillage over five years in a five-field grain-row crop rotation produced similar levels of productivity in terms of yield, energy efficiency, and output of grain and feed units. While productivity indicators under ploughing remained stable relative to the mean, shallow tillage demonstrated a positive trend. This trend is associated with the completion 1513 of the transition period following the cessation of deep ploughing and the shift toward preliminary deep chisel tillage, followed by systematic shallow tillage at a depth of 10–12 cm.Kirje Constructive solution of battery swapping unit in service station for unmanned agricultural robot(Estonian University of Life Sciences, 2025) Jevtuševski, Andrei; Ihnatiev, Yevhen; Lillerand, Tormi; Virro, Indrek; Olt, Jüri; Estonian University of Life Sciences. Institute of Technology. Chair of Biosystems EngineeringThe fully automated battery swapping unit is an essential part of unmanned agricultural robot service, ensuring the continuous operation of the robot by allowing the agricultural vehicle to replace its depleted battery with a fully charged one without human intervention, enabling it to continue its work cycle in the field. Thus, the battery swapping unit is part of service station systems, along with fertilizer filling, water supply, energy generation, and storage systems. This article describes a unique prototype of a battery swapping unit that safely replaces a depleted battery with a fully charged one in 223.5 seconds. The main role is played by the moving battery cart, which transports the battery between the charging and robot positions using a gripper equipped with an electric lock, attached to the actuator, and a V-belt transmission driven by an electric motor. The selection of the optimal rotation frequency of the motor is also discussed in this article.Kirje The effect of a lateral airflow created on nozzle tip on the spray droplets deposition(Estonian Academic Agricultural Society, 2021) Bulgakov, Volodymyr; Olt, Jüri; Pascuzzi, Simone; Gadzalo, Jaroslav; Ivanovs, Semjons; Adamchuk, Valerii; Panasyuk, Volodymyr; Ihnatiev, Yevhen; Estonian University of Life Sciences. Institute of TechnologyImproved application efficacy of a plant protection products by using a pneumatic device to change the dispersion of spray droplets is depended on the intensity of crosswind. The laboratory investigations of the spraying process of plants by means of the nozzles of a pneumatic system determined the quality indicators of pressure in the injection process of 0.4 MPa – the droplet coating density of 19–46 pcs cm2 –1 for the weighted mean droplet diameters (WMD) in the other experimental variants was within 304–543 μm. These indicators were compared with those for the standard, anti-drift and air injection nozzle types in which the droplet coating density was 23–59 pcs cm2 –1 and the weighted mean droplet diameters (WMD) were in the range of 350 to 485 μm. An analytical dependence was obtained of the influence of the lateral airflow and air pressure in the pneumatic system upon the amount of the deposited spray liquid.Kirje Experimental research into impact of kinematic and design parameters of a spiral potato separator on quality of plant residues and soil separation(Estonian Academic Agricultural Society, 2020) Ruzhylo, Zinoviy; Bulgakov, Volodymyr; Adamchuk, Valerii; Bondarchuk, Anatoliy; Ihnatiev, Yevhen; Krutyakova, Valentyna; Olt, Jüri; Institute of Technology. Estonian University of Life SciencesThe experimental investigations carried out in field production conditions have proved that the process of cleaning potato tubers from extraneous material with the use of a spiral separator takes place due to the active conveyance of the heap by the turns of the cantilever mounted cleaning spiral springs. The cleaning spiral springs not only rotate at the set angular velocity, but simultaneously their cantilevered ends perform oscillatory motion, which arises due to the deflection of their longitudinal axes under the action of the weight of the potato heap fed into the work zone of the separator. The results obtained in the process of the field experiment investigations carried out by the authors have provided for obtaining the relations that enable selecting the optimum design and kinematic parameters of the spiral-type potato cleaning devices for the targeted separation rate and, accordingly, estimating their impact on the quality of the performed work process.Kirje Experimental research into operation of potato harvester with rotary tool(Estonian Academic Agricultural Society, 2021) Ihnatiev, Yevhen; Bulgakov, Volodymyr; Bonchik, Vitaliy; Ruzhylo, Zinoviy; Zaryshnyak, Anatoliy; Volskiy, Volodymyr; Melnik, Viktor; Olt, Jüri; Estonian University of Life Sciences. Institute of TechnologyThe experimental research was carried out on a specially designed laboratory-and-field test unit with the use of a hydraulic vertical rotor drive and strain-gauge equipment mounted on a tractor as well as the set of interchangeable coupling pieces for setting the machine's operating duty. Research into the process of breaking two adjacent potato row beds with the vanes of a vertical rotor has been undertaken. A design and process schematic model has been proposed for the operation of the potato harvester. Experimental research into the geometrical parameters of the potato row has been carried out to select the design parameters of potato harvesters. Based on the results obtained during the experimental investigations, the rational ranges have been established for the work process of the rotary potato harvester, the methods of engineering clod breaking tools have been developed. Following the completion of the full factorial experiment, regression functions have been generated. Their analysis has proved that the following factors have the greatest impact on the optimisation parameters: the rotor diameter and the clearance between the rotor and the spherical discs. The following parameters have been optimised based on the response surface analysis: soil separation ratio S = 93.5%, tuber damage rate Pb = 0.97%, total power consumption by unit operation Nа = 18.27 kW, at the following pre-set values of the factors: nр = 77 min–1, Vm = 2.2 m∙s–1, dр = 0.825 m, l2 = 0.3 m. The maximum discrepancy between the results of the theoretical and experimental investigations for determining the design and process parameters of the potato harvester does not exceed 15%. The completed economic testing has proved the advantages of the experimental potato harvester as compared to the existing ones. That said, the separation ratio of the pilot machine is equal to S = 91.4%, which is 23% higher than in the reference case, while its tuber damage rate is equal to 1.14%, which is 5.0% better than in the reference case. The recommendations for the selection of the rational operation duty of the rotary potato harvester as well as the methods for the engineering analysis of the design and process parameters of clod breaking tools have been developed.Kirje Research and justification of parameters for a flexible sectional screw working body(Estonian University of Life Sciences, 2025) Bulgakov, V.; Olt, Jüri; Ihnatiev, Yevhen; Holovach, I.; Trokhanyak, O.; Estonian University of Life Sciences. Institute of Forestry and EngineeringThe article presents a new design of the hinged-sectional working body of a flexible screw conveyor intended for transporting bulk agricultural materials. The influence of the hinge mechanism’s structural parameters on its operational efficiency is investigated, particularly in terms of ensuring the required angular displacement of axes, preventing jamming, and minimizing energy losses. Analytical dependencies are proposed to determine the arc displacement of the ball along friction surfaces, its velocity, and the efficiency coefficient of the hinge mechanism. It is established that the maximum efficiency coefficient ranges between 0.88 and 0.91 when the ratio of the ball radius to the rotation radius of ball centers is within 0.3–0.45. Calculations show that an increase in the conical socket inclination angle leads to a reduction in efficiency. To enhance the overall conveyor efficiency, it is recommended to reduce the hinge axis deviation angle, which results in a larger bending radius of the screw. Specifically, it is determined that the axis deviation angle should not exceed 20–25° while maintaining an efficiency coefficient of at least 0.9. To determine the optimal structural characteristics of the screw working body sections, computer modeling of force load influence on corresponding deformations was conducted. The results show that an increase in torque leads to a greater twisting angle of the section, with the most significant deformation occurring at a minimal number of axial rods. The proposed design improves the efficiency of loading and unloading operations while expanding technological capabilities in transporting grain and other bulk materials.Kirje Research into the parameters of a potato harvester's potato heap distributor, and the justification of those parameters(Estonian Academic Agricultural Society, 2021) Olt, Jüri; Adamchuk, Valerii; Korniushyn, Viktor; Melnik, Viktor; Kaletnik, Hryhoriy; Ihnatiev, Yevhen; Ilves, Risto; Estonian University of Life Sciences. Institute of TechnologyThe low levels of efficiency and general quality when it comes to the use of potato harvesters in difficult soil and climatic conditions substantiate the relevance of the problem which is faced in terms of research by technologically advanced equipment and tools. They are looking to increase the efficiency of potato harvesters. This paper serves to justify the formation of the design and technical parameters of the V-type distributor, which directly acts on the undermined mass to increase the ability of the potato harvester to separate the soil. Preliminary experimental studies have shown that to achieve efficient technological processing in terms of the distribution of the general soil and potato heap, the distributor must possess the appropriate technological and design parameters. Calculations which have been carried out by using as a basis the theoretical dependencies that have been obtained serve to allow us to determine the optimum speed of progress through the heap, using the following design and kinematic parameters: Vel = 2.0 m s–1, А = 0.35 m, hv = 0.22 m, Δ = 0.08 m, bel = 1.2 m. The allowable speed for heap movement will be [V] = 1.62 m s–1, which will ensure the prevention of any heap clogging in front of the distributor. An analysis of the dependencies which have been obtained during the work shows that rational values for the distributor wing’s fitting angle fall within the range of α = 40°.