Ultra-high frequency (UHF) microwave radiation can effectively suppress soil microorganisms, insect eggs, and larvae within the depth of radiation penetration. Since the efficiency of thermal soil treatment is largely determined by the emitter’s configuration, this study aimed to identify the most effective waveguide type. Three designs were evaluated – standing wave, traveling wave, and beam-type chambers. Using COMSOL Multiphysics, the authors simulated the thermal effects of microwave radiation on a 100 mm soil layer with moisture levels of 5%, 10%, and 20%. Depending on the waveguide type, the irradiated surface area varied from 40 × 88 mm to 134 × 201 mm, with magnetron antenna power ranging from 650 to 5000 W at a frequency of 2450 MHz. The simulations demonstrated that direct contact between the waveguide and the soil is unnecessary for effective treatment. While microwave efficiency increases with soil moisture, higher moisture levels also lead to non-uniform volumetric heating. Comparative analysis revealed that for soil moisture between 10% and 20%, the traveling wave chamber is the superior choice, transmitting 72-88% of source energy and achieving 60-85% energy absorption. Optimal performance, characterized by high power output and heating uniformity, was observed using a traveling wave chamber at 10% soil moisture. These simulation results, pending experimental verification, provide a foundation for developing specialized microwave systems for thermal soil treatment in greenhouses and hotbeds.

The operational efficiency of agricultural drones is currently constrained by the lack of mobile, field-based service solutions. To address this, the use of autonomous service platforms, or “droneports,” is required. This study investigates approaches for automating ground-based support for agricultural unmanned aerial vehicles (UAVs) through the development of a folding, modular conveyor-type droneport. The proposed design features a mobile service platform that utilizes a folding roller conveyor to transport heavy-duty drones. The conveyor is driven by a sequential toothed belt system powered by a NEMA23/NEMA24 stepper motor (5 A phase current) coupled with a 1:20 planetary gearbox. Full-scale laboratory testing was conducted on a 1.88 × 0.90 m prototype at speeds of 0.05 to 0.15 m/s across horizontal and inclined (3° and 6°) surfaces. An EFT G630 agri-drone, weighing 70 kg with a 100 kg payload capacity, was used to simulate extreme operational loads. Results showed that power consumption during transport remained below 30 W, even at a 6° incline. The system demonstrated high fault tolerance; the failure of individual rollers did not disrupt overall operation. The experimental findings confirmed the feasibility, energy efficiency, and reliability of the folding conveyor module, highlighting its potential as a mobile servicing infrastructure for agricultural UAVs

Determination of crude protein in animal feed using photoluminescence spectroscopy can significantly accelerate the feed preparation process. This study aimed to analyze the dependencies of photoluminescence parameters in sunflower and soybean oilcakes on their crude protein content to identify informative parameters and optimal spectral ranges. The experiment was conducted using a SM 2203 diffraction spectrofluorometer. The research involved determining the excitation and photoluminescence spectral characteristics of sunflower and soybean oilcake particles ground to 1.8 mm with varying crude protein levels. Integrated spectral parameters, specifically absorptivity and photoluminescence flux, were calculated. The excitation characteristics of the studied feeds are located in the 300-500 nm range and represent a superposition of peaks at 290, 362, and 414/424 nm, with a weaker peak at 485 nm. It was found that spectral absorptivity increases with higher protein content. The dependencies of integrated photoluminescence fluxes on protein content are statistically significant (coefficients of determination = 0.84-0.99) and can be approximated by linear regression equations. For the photoluminescencebased determination of crude protein, the most suitable excitation wavelengths are 362 and 414 nm for sunflower oilcake, and 362 and 424 nm for soybean oilcake. For a unified methodology, it is advisable to use an excitation wavelength of 362 nm while recording the photoluminescence flux in the 410-600 nm range. The resulting spectral parameters and regression equations can be utilized to develop rapid-testing instruments and optimize technological processes in the preparation of feed mixtures.

To preserve the soil cover during forage harvesting on waterlogged soils, it is advisable to use a crawler with elastic rubber-cord tracks. The research aimed to develop a physical-mathematical model assessing the ability of elastic flexible support devices to reduce loads acting on the support branch of a triangular unsprung crawler propulsion system with a support idler wheel during its interaction with waterlogged soils. The optimal parameters of the external cushioning of the track chain of a triangular unsprung crawler propulsion system with a support idler wheel were determined analytically. In contrast to a non-cushioned propulsion system, the highest pressure on the supporting surface is observed when the axis of the road wheel or idler wheel is positioned above the midpoint of the next traversed track link, while the lowest pressure occurs when it passes over the hinge joint. It was established that the ground pressure of the propulsion system can be described as the interaction of two processes: a harmonic function in a coordinate system fixed relative to the soil, and a sequence of impulses in a moving coordinate system associated with the propulsion system. The developed physical-mathematical model of loads acting on the support branch of a triangular unsprung crawler propulsion system with a support idler wheel makes it possible to determine the characteristics of the ground pressure exerted by the propulsion system. Pressure distribution diagrams beneath the support section of the undercarriage for various time points showed the absence of significant pressure peaks that form the track depth on waterlogged soils, which demonstrates the damping capabilities of the applied rubber-cord tracks. The developed model is applicable to the determination of optimal design parameters of the tracked propulsion system.

The operation of internal combustion engines (ICE) using water as a liquid heat carrier leads to intense corrosion and deposit formation. Therefore, it is advisable to incorporate a corrosion inhibitor with a high protective effect into the coolant composition. The study aimed to evaluate the efficiency of a coolant containing a carboxylate corrosion inhibitor and the corrosion resistance of metal elements in an ICE cooling system. The authors developed a prototype coolant, VN-RU-30, with the following composition: 48% water, 48% ethylene glycol, and 4% carboxylate corrosion inhibitor. The prototype was compared with commercially available coolants, OZh-40 LENA and CoolStream Standard 40. According to GOST 28084-89, the physicochemical parameters of VN-RU-30, OZh-40 LENA, and CoolStream Standard 40 were determined, and their corrosive effects on samples of M1 copper, POS-40-2 solder, L-63 brass, St3 steel, SCH-20 cast iron, and AK-7 aluminum alloy were compared under static conditions. The protective effect of the VN-RU-30 prototype was found to be comparable to the reference coolants. To evaluate the protective efficiency of the VN-RU-30 coolant, the authors conducted tests on a model simulating an engine cooling system subjected to corrosion for 336 hours. It was established that VN-RU-30 neutralizes corrosion products on metal surfaces and effectively inhibits further corrosion processes (protective effect exceeding 98%). Field corrosion tests lasting 46 months demonstrated the integrity of the metal components in the ICE cooling system when using VN-RU-30, compared to water, which intensified corrosion and deposit formation. The results confirm the high protective efficiency of the VN-RU-30 coolant for ICE cooling systems; it is advisable for use in engine operation, restoration, and long-term preservation.

A serviceable double-disc coulter, forming a dense and evenly embedded seedbed, ensures good germination and yield of grain crops. Significant abrasive diametral wear of the coulter discs during operation necessitates their frequent restoration. The study aimed to justify the selection of technical means for welding a repair part in the form of ring fragments, using coulter discs as an example. The selection of technical means for welding the repair part was based on a multi-criteria evaluation. The methodology employs a ranking comparison of characteristics and parameters, followed by a criterion-based condition of maximizing or minimizing indicators. The following criteria were considered: technical–economic criterion (the welding machine and welding type); technological criterion (the electrode grade); weld joint criterion (the electrode diameter); and strength criterion (the repair part material). The final evaluation was performed using a generalized integral criterion – the minimum distance to the goal – obtained through analysis of evaluation graphs of multi-criteria models. The authors examined four types of welding machines, seven electrode grades with diameters of 2.5, 3.0, 3.2, and 4.0 mm, and four steel types as the repair part material. Based on the calculations and the generalized integral criterion of minimum distance to the goal, the following technical means were selected: the welding machine Kedr VD-500.01 (μ_{₁_min} = 3.66); the electrode grade: UONI-13/45 (μ_{₂_min} = 4.19); the electrode diameter: 3.2 mm (μ_{₃_ min} = 3.87); and the repair part material: 30MnB5 steel (μ_{₄_min} = 4.00). The selected primary technical means, based on a heuristic multi-criteria evaluation of 23 indicators using the generalized integral criterion of distance to the goal, are recommended for implementation in the technological process of restoring coulter discs by welding repair parts in the form of ring fragments.

Against the backdrop of the dependence on imports, import substitution of spare parts for agricultural machinery and equipment is a pressing issue. The use of additive technologies opens up new prospects for designing working parts with specified physical and mechanical properties adapted to specific operating conditions. The study aims to develop knives for feed mixers based on innovative technologies for the modernization of agricultural machinery, based on the substantiation of the geometric parameters of the knife’s connecting elements. The objects of study were square and star-shaped knives used in KUHN and Seko horizontal feed mixers. The author proposes a design for a prefabricated (modular) knife for a feed mixer and dispenser. The cutting parts of the experimental knives are manufactured using SLM printing from 17-4PH and 316L steels, and the flange is manufactured using FDM printing from ABS-based engineering thermoplastic reinforced with 15% carbon fibers (REC X-Line ForMAX). The feasibility of achieving an interference-fit connection on semi-circular splines, secured by a flange collar, was theoretically substantiated and confirmed using simulation modeling. The critical interference fit value was determined to be less than 0.16 mm. The high quality of additive manufacturing was experimentally confirmed. The hardness of 17-4PH steel reached 51.4 HRC, approaching the level of serial 9ХС steel (60.4 HRC); the flange hardness was 86.7 Shore D, indicating optimal FDM printing conditions Steel 17-4PH is the optimal material for manufacturing modified knives using 3D prototyping, providing the best combination of wear and corrosion resistance. The durability of knives can be further increased by using SLM printing to impart specific physical and mechanical properties to the printing material, followed by surface hardening using ultra-high-frequency induction heating in boron containing coatings. This method produces wear-resistant layers up to 1.2 mm deep and with increased hardness. The practical implementation of the developed prefabricated feed mixer knife will enable the rapid production of worn knives in the absence of original spare parts, thus eliminating equipment downtime and reducing reliance on imports.

Significant wear of metal components in agricultural machinery and equipment necessitates their restoration using the most rational and cost-effective methods. The research aimed to identify the most promising and economically viable method for the designing and repair of agricultural machinery parts using additive technologies. An analysis of metal 3D printing methods based on equipment cost and process complexity indicates the feasibility of using devices for spatial orientation of the welding torch when employing widely available welding wires of various compositions. For agricultural enterprises, the most rational approach for restoring the geometry of worn parts and manufacturing new spatial metal structures is the use of semi-automatic welding technologies. The DED-W/WAAM/3DMP technology offers the highest productivity (up to 800 cm³/h) and the lowest cost among metal printers (without the use of specialized robots). Additionally, milling and engraving machines can be utilized both for metal printing and for subsequent mechanical processing. Field test results of working elements reinforced with intermittent wear resistant beads using the WAAM method show that after 24.785 hectares of operation, the linear wear of the blade width on reinforced shares is, on average, 10-11 mm less than that of non-reinforced shares. The integration of additive technologies into the maintenance and repair system of large and medium-sized agricultural enterprises – based on milling and engraving machines and semi-automatic welding kits – will enhance the efficiency of 3D printing by welding in the restoration of machine components while reducing the wear rate by 30-40%.

Ensuring regulated and stable steam pressure in a steam-plasma burner device is a priority objective in the design of heating systems for agricultural enterprises. Existing control methods based on standard PID-type controllers do not provide high efficiency of the heating system. The research aimed to develop a computer model of an automated steam pressure control system for a steam-plasma burner device with a capacity of up to 1 MW and to determine the optimal controller coefficients ensuring steam pressure stabilization. The computer model of the automated steam pressure control system for the steam-plasma burner device, developed in the Matlab/Simulink environment, includes a radial piston pump, a distribution unit, a steam-plasma generator, and a control system based on a proportional-integral controller. Dynamic processes in the system were simulated at fixed shaft rotation speeds of 100, 200, 300, and 477 rpm and a steam pressure range of 0 to 23 bar. The authors examined the influence of the PI controller parameters on transient processes and operational stability. Computational experiments resulted in determining optimal PI controller coefficients, providing a minimum transient time (no more than 7 seconds) and a pressure deviation not exceeding 4% of the setpoint value. The obtained results confirm the effectiveness of the proposed control method and the feasibility of its practical implementation in automatic control systems for liquid-fuel burners used at agricultural enterprises.

Manual and electric pruners used for tree pruning in industrial horticulture are insufficiently effective. An electric pruner with an improved magnetic circuit (a stator and an armature of the electric motor) and optimal energy characteristics will contribute to the effective development of the industry. The research aimed to develop a linear electric motor (LEM) for driving a manual electric pruner and to adapt its technical characteristics (cutting force) to the conditions of industrial horticulture. In the proposed LEM design, the cutting force is generated by two magnetizing coils (working and starting). The first coil is mounted on a stationary magnetic circuit, while the second is located on a magnetic system featuring a non-magnetic insert. The linear dimension of the armature non-magnetic insert was varied to 5, 10, and 15 mm. Theoretical values of the armature traction force depending on the size of the non-magnetic insert, obtained through simulation in the ElCut software, were compared with experimental data. The research results showed that the longer the non-magnetic insert, the greater the effective stroke length of the second (starting) coil. For a non-magnetic insert size of 5 mm, the stroke length was 3 mm, while for a 15 mm insert, it was 9 mm, respectively. It was established that with an increase in the size of the non-magnetic insert, the starting force decreases from 27 to 17 N. The total force generated by the two magnetizing coils enables the system to move at idle at the initial moment. At the end of the working stroke, under the action of the first (working) coil, a 6 mm diameter branch is cut with a force increasing from 25 to 132 N. The theoretical values of the total traction force practically coincide with the experimental curve. The obtained characteristics of the branch cutting force and the operation of the linear electric motor can be used in the design of manual electrified puners.

Adjusting the concave clearance in a threshing-and-separating unit of a combine harvester directly impacts threshing quality and grain loss. This study aims to develop an analytical relationship between the actuator stroke of the electro-hydraulic drive and the clearance size, enabling the implementation of active control algorithms. The research focuses on the tangential-type TSU of the ACROS530 combine harvester. The methodology is based on a kinematic analysis of the concave suspension mechanism, utilizing geometric modeling of the links and determining joint coordinates via the intersection of circles. Based on the resulting model, the authors established the relationship between the clearance and the hydraulic cylinder stroke to formulate the inverse function required for control systems. To minimize computational load, a cubic spline approximation was performed, ensuring high precision within the operational regulation range. The proposed adaptive electro-hydraulic drive scheme incorporates closed-loop control for position, speed, and pressure. The proposed architecture is characterized by reduced energy consumption during load holding and the ability to adapt to varying operating conditions. The study results can be applied to the design and modernization of regulation systems for the threshing and separating units of modern combine harvesters

Demographic aging of the workforce and technological modernization of the agro-industrial complex determine an objective need for the development of an adaptive competency-based model for corporate training of older workers (aged 50+) at agro-industrial enterprises. The research aimed to develop and provide theoretical grounds for a pedagogical model for corporate training of older workers in the agro-industrial sector, taking into account industry-specific, age-related, and institutional characteristics. The theoretical and methodological framework includes andragogical, competency-based, acmeological, and socio-institutional approaches. The author employed systemic and comparative-analytical methods, content analysis of scientific and regulatory sources, expert assessments, and pedagogical modeling. The presented model integrates practice-oriented on-the-job training, personalized learning pace and formats (modular micro-courses), cross-generational mentoring, capitalization of empirical competences, mandatory modules on occupational safety and biosecurity, and phased digital inclusion focused on “minimally sufficient digital competence.” The article proves that implementation of the model increases operational efficiency and reliability, reduces injury rates, strengthens the engagement of workers aged 50+, promotes cross-generational continuity, and aligns with national active aging policies as well as international recommendations of the International Labour Organization. The added scientific value of the study outcomes consists in refining the content of corporate training for workers aged 50+ specific to the industry, formulating principles of digital inclusion, and proposing evaluation criteria that combine production and socio-psychological indicators. Practically significant is the possibility of using the model as a theoretical and methodological foundation for designing standard corporate training programs at agro-industrial organizations.