The optimal technological varinat for the production of vegetable crops can be determined, taking into account economic aspects. This variant presumes comprehensive selection of process operations using available machine systems and modern varieties and hybrids of planting material. To solve the development problems of the vegetable and potato growing industry in the long term, taking into account modern technologies for growing crops, managing machine-technological systems and improving the quality of technological and production decisions made in the machine production of vegetables, the authors have developed a conceptual technical and technological model for the machine production of onions, carrots and beetroots. The off ered model includes structural units (varieties, means of protection, machine-technological systems), resources (availability of seed material, machine-technological systems of crop production and crop rotation), processes and performance indicators. The model takes into account the set of elements of the technological method for obtaining products by means of transport, transmission, diagnostic and information means, organized into integral technological systems of production subdivisions. The developed model will take into account a number of factors: the implementation of production processes (sequence, timing of implementation, and the type of performed mechanized operations); requirements for material, financial, labor and technical resources; documentation for each stage of operations and quality indicators that determine the performance results at each stage. The obtained function of the commercial production of onions, carrots, beetroots, and potatoes, presented by the graph, will help determine the effi ciency and the evaluation of the optimal technical characteristics.

   To design intelligent transport and technical means, it is necessary to improve the methodological provisions and software for multi-criteria optimization of the functional properties of innovative mobile energy means. The right choice of optimization methods is necessary to design a reliable mathematical model. A comparative analysis of methods for optimizing problem solving for agricultural engineering showed the applicability of single-criterion methods in optimizing simple design parameters of single-purpose problems (development of parts, technical and technological characteristics of individual objects). Multicriteria optimization methods are applicable to solving problems with the defi nition of several objective functions with a large number of functional and criterion constraints, as well as variable parameters, where each parameter is not inferior in importance and relevance to each other (agricultural enterprise management, design of mobile power vehicles, combines and other agricultural machines). Vector optimization methods are applicable for solving a multicriteria optimization problem with a set of possible (permissible) solutions (designing elements of units, machine units and equipment for agricultural production). The authors have analyzed the existing software tools for solving optimization problems. They have found it necessary to develop software tools taking into account simultaneously up to 20 criterial and functional constraints, up to 50 variable parameters and more than three equally important objective functions, where each parameter has no precedence over the others.

   Machine potato harvesting is ineff ective on waterlogged soils at a moisture content of more than 24 % as rod gaps are clogged with rocks and tubers. The potato harvester design can be improved with an intensifier in the form of a clamping conveyor with flat blades set at an angle. The authors analyzed the conditions for ejecting tubers from the rod gaps of the separating elevators and determined the design parameters of the intensifier: the distance between the bars of 30 mm, the diameter of the bars of 11 mm; the inclination angle of the intensifi er blade to the plane of the conveyor belt of more than 82 °. Provision is made that when the tubers are pushed out, the gap between the rod and the tuber should be less than 5 mm. Based on the goal of increasing the completeness of soil separation and excluding damage to potato tubers, theoretical studies have established the kinematic parameters of the intensifi er: a conveyor speed of 0.8 m/s to 1.4 m/s, an elevator rod speed of 1.0 m/s to 1.8 m/s. To prevent tuber damage, the impact velocity of potato tubers with the blades must be less than 2.2 m/s. The blade pitch should equal 210 mm. Agrotechnical assessment of fi eld tests of the KPK-2-01 potato harvester with a separating elevator intensifi er carried out on the premises of the “V. D. Bykov’s Raduga Farm” located in Kamyshi, Kursk district, Kursk region, showed an increase in the completeness of soil separation by 8.3 %.

   The milking and dairy equipment of a number of domestic enterprises is very worn out. The wear of milking equipment is caused by non-compliance with their maintenance and repair. To assess the reliability of individual elements and systems of milking machines used in production and to determine the ways to improve their operational characteristics, the authors analyzed the operation of enterprises located in the the Lyskovo district of the Nizhny Novgorod region using the most common linear milking machines. They analyzed failures and the time spent on ensuring the operability of milking systems. As a result of the study, the structure of failures for various systems and elements of milking machines was determined. The study determined the values of individual reliability indicators – operating time for failure and the failure fl ow parameter. The value of the availability coefficient, which characterizes both reliability and maintainability, was determined. The analysis of the reliability indicators of milking units showed that the largest number of failures of linear milking units falls on milking machines (41.2 %), on the primary milk processing system (16.5 %) and the vacuum system (11.3 %). In the vacuum system, most of the failures are associated with the vacuum regulator (54.5 %). In the dairy system, group counters are vulnerable elements. In milking machines, faulty teat cups account for 45 % of failures, in which the nipple rubber wears out intensively. The lowest operating time for failure of milking machines and the dairy system indicates the need to improve their designs and the system of technical service. For elements of primary milk processing systems, the washing of milking equipment, and the vacuum system, the time required to eliminate failures is more than two hours, therefore, it is recommended to organize an exchange pool of spare parts and a modular repair method.

   There is a need in deeper research on the influence of the pre-milking udder preparation time during machine milking on the indicators of milk removal of cows. For this purpose, the method of periods was used to study 14 first-calf heifers, divided into two groups of 7 head: quickly and slowly milked. Cows were milked with the Astronaut A4 units, provided that the intervals between adjacent milkings were equal. Depending on the duration of the pre-milking udder preparation, four tests were carried out for each cow: one control and three experimental (I-III), five observations each. The duration of pre-milking preparation in the control was up to 120 s, in the first experiment – 121-150 s, in the second – 151-180 s, in the third – more than 180 s. It was experimentally established that the duration of the pre-milking udder preparation of up to 120 s contributes to the optimal intensity of milk ejection in fast and slowly milked cows. With longer pre-milking preparation, the duration of cows’ staying in the milking box increases by 6.7…32.8 % (P < 0.01) and the intensity of milk ejection decreases by 7.0…13.3 % (P < 0.05). The duration of the pre-milking udder preparation of slowly milked cows over 120 s leads to a decrease in one-time milk yield and the intensity of lactation, an increase in the duration of milking and the average duration of milk removal from the udder quarters. In fast milked cows, the duration of the pre-milking preparation of the udder does not affect the milk removal indicators, but increases the time spent in the box by 10.6 … 32.8 %.

   The pelleting process was stable at a temperature of the pelleting press barrel of 70…80 °С and the temperature of pellets at the exit of 65 to 70 °С. Humidity control was carried out in accordance with GOST 13496.3-92, the crumbling of pellets – in accordance with GOST 23513-79, GOST 22834-87. Fifteen experiments were carried out in three repetitions according to the matrix of the orthogonal central composition plan of the second order. The factors of the experiment included the matrix thickness, the moisture content of the raw material and the mass fraction of soybean grains in the raw material. The crumbling of the obtained pellets served as the optimization criterion. Based on the experiment results, an adequate regression equation was obtained. It was established that the smallest percentage of pellet crumbling is observed in the moisture content ranges of raw materials of 50 to 60 % and the mass fraction of soybean grinding in raw materials of 15 to 16.5 %. With a fixed value of raw material moisture content, the optimal thickness of the pressing matrix corresponds to the range of 27.5 to 39.0 mm, while the mass fraction of soybean grain in the raw material is 15 to 25 %. With a fixed mass fraction of soybean grain, the optimal values of the pressing matrix thickness range between 30 and 40 mm, the values of the initial moisture content are 40 to 60 %. To obtain pellets consisting of precrushed and moistened soybean chaff and soybean grains with the crumbling rate of less than 12 %, the thickness of the matrix with holes with a diameter of 10 mm should be 30 to 40 mm, the mass fraction of soy in the raw material should correspond to 15 to 16.5 %, and the moisture content of raw materials should equal 51 to 60 %.

   The experimental study presented in the article forms the basis for designing a dispenser servicing a robotic feed table on livestock farms. In the introduction, the author analyzes trends in the development of machines for on-farm production of compound feeds using dosing and weighing equipment, and describes the role and key performance indicators of the use of compound feeds of on-farm production for livestock breeding complexes. The articles presents a method for optimizing the design parameters of screw-type feed additive dispensers, a schematic diagram and a photo of an experimental installation. To control the electric motor of the experimental installation, a mathematical model was developed that takes into account the electric motor speed. A second-order mathematical model was used as a mathematical framework for processing experimental data, constructing response surfaces and regression equations. The experiment assumed a five-fold weight measurement of the dosing error of feed additives for each type of the screw design.

   When cultivating row crops on depleted peatlands introduced into agricultural circulation using the peat soil farming practice, post-sowing tillage (harrowing, inter-row loosening, hilling and thinning of plants in rows) changes the thermophysical properties of peat, increasing the probability of a peat fire. To study the temperature and humidity mode of the upper fire-hazardous layer of the peat soil on a drained fi eld used for vegetable and fodder crop rotation, studies were carried out on the drained Kalskoye swamp in the Ryazan region. Measurements of the soil parameters were carried out on its surface and in the upper layer of 0 to 5 cm. When modeling spontaneous combustion and forced ignition of the peat soil, the results of experimental fi eld studies were used. Based on the practical data obtained, the authors proposed mathematical dependencies for calculating the possibility of spontaneous combustion of peat soils. Comparison of experimental and calculated data showed that their discrepancy is 2.2 % to 15.6 %. The obtained mathematical dependencies can be used to predict the probability of fires on peat soils. The authors propose a scheme of a new method for monitoring the fi re hazard situation on drained peatlands during their introduction into agricultural production. This method of monitoring, based on the criterion of uneven heating, is useful for taking preventive measures against the peat soil ignition on agricultural land.

   To perform the state-assigned task on determining the functional characteristics (consumer properties) and effi ciency of agricultural machinery and equipment, the author has developed a draft methodology for calculating standard costs based on regulatory documents. The median calculation method was chosen for this purpose. The standard costs include: labor costs with accruals for employee compensation payments, for the purchase of inventories, movable property (fixed and intangible assets), utilities, etc. This work on calculating the standard costs is somewhat specifi c as tests are carried out on forty groups of machines (within each group there are several models), on ten machine testing stations (MTS) operating in different regions of the country. Initial calculations showed a signifi cant (up to 50-60 %) difference in standard costs for the same groups of machines on the MTS. In the course of updating the methodology, the author applied the normative method to some cost items: the average monthly nominal wages of plant and animal husbandry workers, fuels and lubricants were used to calculate labor costs – the norms of hourly fuel consumption of a tractor of the corresponding class multiplied by the planned operating time required to obtain an assessment of the functional indicators of the corresponding group of machines. There was a convergence of standard costs for the same-named groups of machines, and as a result, the MTS cost standards began to diff er by 8 to 10 %. The methodology is recommended for use to calculate the standard costs of machine testing stations of the Ministry of Agriculture of Russia in the implementation of state-assigned tasks.

   The development of universal diagnostic parameters with increased information content and the possibility of prompt registration and processing will help assess the current state of individual elements and the diagnostic object as a whole. As a universal diagnostic parameter characterizing the technical condition of the internal combustion engine, the authors propose to use the reaction impulse of the engine supports, the value of which depends on the crankshaft speed. Using a laboratory installation that includes a D-243 diesel four-stroke four-cylinder engine and a set of measuring equipment, the authors studied the process of changing the impulse of the reactions of the internal combustion engine supports when changing the crankshaft speed in the idling mode. When conducting research, they used methods of regression, system and statistical analysis. It has been established that in the crankshaft speed range of 600 to 2200 min^–1, the maximum value of the bearing reactions for each cycle of engine operation changes from 345 to 122 N. In the range of 600 to 1000 min^–1, the minimum value of the bearing reactions for each engine cycle changes –272 to –305 N and increases to –109 N at a maximum frequency of 2200 min^–1. The maximum momentum of the support reactions is observed at a crankshaft speed of 1000 min^–1 and averages for positive and negative reactions of the supports, respectively, 17.34 and –17.35 kNs. At the maximum speed of the crankshaft, the momentum of the support reactions reaches 9.28 and –9.29 kNs for the positive and negative reactions of the supports, respectively. The results obtained can be used to improve the methods for diagnosing internal combustion engines, as they can help exclude the infl uence of the crankshaft speed on the measurement result.

   The parameters of electromechanical transmission for the tractor of 0.6-0.9 traction class are selected based on the analysis of traction and hitching characteristics of the complete machine. The authors have made theoretical calculations of the operating characteristics of the prototype tractor with an internal combustion engine and the tractor layout with an electric drive, traction calculation of the prototype tractor and the tractor layout, and calculation of the characteristics of the electric drive and electric motors. For the calculations, a six-speed manual variable gearbox was selected. The initial data for performing the calculations were obtained from the results of tractor traction tests in the North Caucasian machine test station. Two profile backgrounds of the support base were selected: a fi eld prepared for sowing (fallow) and stubble. As a result of research, it was established that a tractor-model designed on the basis of the self-propelled chassis of a pulling class 0.6 to. 0.9 with capacity up to 50 kW on the “Field prepared for sowing” background reaches the greatest towing effi ciency (0.53) with the 15 kW electric motor and the greatest drawbar pull (5.78 kN) with the 18 kW electric motor. On the “Stubble” background, for 15, 18 and 22kW electric motors, the pulling effi ciency is 68%, but the tractor layout with the 22kW electric motor can develop the maximum drawbar pull of 11.35kN. The maximum pulling power of 16.7 kN is observed in the prototype tractor with an internal combustion engine. Therefore, the 15-kW electric motor can be the only most suitable substitute for a combustion engine by traction efficiency.

   Modern repair production that implements traditional technologies for making restorative coatings has lost its relevance, since it cannot provide the necessary physical and mechanical properties of the coatings. The problem is that in modern metallurgy there is no line of repair additive materials with high strength and technological properties. Therefore, the issues of searching for innovative materials and technologies for their application on the surface of worn parts are relevant and require fundamental research. The aim of the work is to study the physical and mechanical properties of ceramic coatings obtained by short-pulse laser treatment. To achieve this goal, ceramic compositions based on boron carbide, additionally doped with boron nitride (0 to 40 % BN), magnesium oxide (2 to 10 % MgO) and lithium (5 to 25 % LiO), were used. The scientific novelty of the research lies in the application of selective laser sintering technologies in the formation of thin coatings (up to 200 μm) under conditions of a short-pulse laser refl ow of powder media. To assess the physical and mechanical properties, laboratory research methods were used, in particular, analysis of the microhardness of the created restorative coatings, microstructure and tribological performance indicators using modern techniques and instrumentation. The research results confirm the possibility of practical implementation of restorative coatings based on ceramic compounds. The multi-layer ceramic coatings (B4C–BN–MgO–Li₂O) up to 200 μm thick showed good workability, low coeffi cient of friction (0.18) and the ability to work under high dynamic loads in the absence of intensive lubrication. The structure of the coatings has a dense adhesive zone with no visible defects. The presented results of studying the physic-mechanical properties of ceramic coatings have high research credentials and practical signifi cance, and their application will improve the durability of machine parts in the conditions of their operation.

   Reliability indicators for 0.4-110 kV overhead transmission lines need to be adjusted due to the lack of data on current values of reliability indicators for power system equipment. The authors’ analysis of official statistical data on the number of emergency and scheduled outages in the branches of PJSC “Rosseti Tsentr” and “Rosseti Tsentr i Privolzhye” revealed deviations of the reliability indicators of electrical equipment of power systems and power grids from those presented in RD34.20.574. Also, the analysis showed that the standard presented no values of average downtime for planned outages of 0.4 kV and 6-10 kV overhead power lines. Reliability values of 0.4-110 kV overhead power lines were determined. Failure rate of 0.4 kV overhead lines made 6.2 to 7.04 year^-1/100·km, of 6-10 kV overhead lines – 5.27 to 8 year^-1/100·km. The “Orelenergo” branch, a failure flow of 35 kV overhead lines was 0.57 year^-1/100·km, and 110 kV overhead lines – 2.83 year^-1/100·km. The calculated value of the average restoration time for 0.4 kV networks was 1.88 h; for 6-10 kV networks – 3.1 h; 35 kV – 6.8 h; 110 kV – 9.5 h. The estimated average number of intentional outages for 0.4 kV networks was 0.1 year-1; for 6-10 kV networks 0.72 year^-1; for 35 kV networks 0.4 year^-1; for 110 kV networks 0.51 year^-1. The average idle time of 0.4 kV overhead lines and 6-10 kV overhead lines amounted to 13.6 hours and 10 hours, respectively. The calculated average downtime of 35 kV overhead lines and 110 kV overhead lines amounted to 24.7 hours and 37.6 hours, respectively. The received data specify modern reliability values of electric 0.4-110 kV networks that can be used when planning measures on developing networks and reconstructing them.

   The pellet size can be determined without stopping the shell build-up by the dielectric permittivity of the pellet mass. To confi rm this hypothesis, mathematical expressions describing the relationships between the amount of materials of the pellet shell, pelleted objects and air have been compiled and analysed. During theoretical study of the shell build-up, assumptions were made on simultaneous increase in diameter of the pellet objects and on spherical shape of the formed pellets. The authors made calculations using the example of flat electrodes with the pellet mass placed between them. The pellet mass is treated as a material substance that fills the space between the electrodes and has a variable dielectric permittivity. It was found that increasing the pellet size leads to a decrease in the dielectric permittivity of the pelleted object structure. The dielectric permittivity of the medium is proved to be a function of the object diameter that depends on the number of objects between the plates. The identifi ed relationship was used to obtain information about the shell build-up in a continuous mode. Under production conditions, the dielectric permittivity of the pellet mass may be measured by the value of alternating electric current flowing through the medium under analysis.