bluuebunny/crossref_metadata_2025 huggingface dataset:
MATHEMATICAL MODEL OF A PNEUMATIC RELAXATION OF SEAT SUSPENSION WITH ENERGY RECUPERATION
Authors: Lyashenko M. V , Shekhovtsov V. V , Iskaliev A. I
Published: April 2022

Simulink MatLAB, амплитудно-частотная характеристика. The paper proposes a mechanism and an algorithm for controlling a single-bearing pneumatic relaxation suspension system with energy recovery of oscillations applied to the standard seat of operator of Sibeko traction vehicle. Experimental studies of the static characteristic of a pneumatic suspension of a standard seat with a nonlinear elastic-damping characteristic have been performed. A mathematical model of a pneumatic relaxation seat suspension with two additional volumes of air is created, between which is installed an air motor - recuperator, which is activated by the flow of air from one additional volume to another. As a result of computational studies using the XY Graph Simulink MatLAB block-tool, the working elastic-damping characteristic of the simulated suspension system was obtained. The mathematical model, created taking into account the main provisions of theoretical mechanics and gas dynamics, realizes the concept of control of a single-bearing suspension system with a non-linear elastic-damping characteristic and absorption of vibrational energy at the end of compression and rebound strokes with a change in the direction of movement of the sprung mass. Calculation studies were carried out in the Simulink MatLAB software package. The working capacity of the mechanism and method of control of a single-bearing suspension system, realizing the necessary characteristic, has been confirmed. For the preliminary evaluation of the vibration-protective properties of the seat, amplitude-frequency characteristics of the transmission coefficients of the nominal and proposed suspensions were constructed. The performed comparative analysis of the amplitude-frequency characteristics revealed a noticeable improvement in the vibration protection of the pneumatic relaxation system of suspension with energy recovery of oscillations in comparison with the nominal one both in the region of resonant disturbances and in the resonant region. Based on the results of the analysis, the main directions for further improving the vibroprotective properties of the proposed suspension system are outlined.
Application of statistical methods for quality control of measurement processes in the enterprises of technical service of agroindustrial complex
Authors: Pchelkin A. A
Published: April 2022

The attention to statistical methods of quality control is driven by their reliability in case of the small sample volumes in comparison with continuous control. The article shows the reasons of delaying of introduction of statistical methods in the enterprises of technical service of agroindustrial complex. The value of statistical quality control of test and measurement processes is pointed out. It is confirmed by the standardized requirements to the quality management and by the assessment of impact of this control on failures of products in operation. The use of statistical control allows to stabilize in more short timeframes the production on high-quality level. The analysis of standards and technic specifications for machinery production shows that the acceptance rules for machinery generally indicate the sample volume equal to 2% of batch of machines. This is only 1 machine of daily batch of 50 machines. At that, the risk of the fact that a consumer will receive defective products is 26%. The control of a single machine in the sample shows the imperfection of acceptance rules. Despite the availability of regulations on statistical quality control, it has not become widely used in practice in the field of domestic agricultural and automotive engineering and technical services. It is necessary to determine the problems of statistical quality control of test and measurement processes and the ways of its implementation; to establish the reasons for the lack of attention to statistical quality control. It is required to substantiate the ways for its widespread use in the technical service and production. As research techniques, it is proposed to apply the information retrieval, statistical methods of data collection, analogy methods and morphological analysis.
PERSPECTIVE STRUCTURES OF MACHINE AND TRACTOR UNITS FOR OPERATIONS COMBINATION
Authors: Maslov G. G , Zhury I. A
Published: April 2022

Perspective structures of machine and tractor units for combination of technological operations when performing of the field mechanized works are offered. Combination is based on the operations coinciding on agrotechnical terms of the performed works: introduction of mineral fertilizers - stubble processing of the soil; hulling of an eddish - application of fertilizers; chisel plowing soils - introduction of mineral fer-tilizers; crops of intermediate cultures - processing of the soil and etc. Efficiency of combination is determined by higher quality of the performed works without gap by time, moisture economy, elimination of the losses brought in the soil of materials (seeds, fertilizers, pesticides), respect for threading and rhythm of production processes, decrease in need for the equipment and a labor power and all cost types (labor, cash, energy). All this promotes increase in competitiveness of the made products. Completion of the offered new structures of multipurpose aggregates is based on use of the serial basic machines checked in production (deep-rippers, plows, cultivators, disk tools, seeders, etc.) equipped with various devices for introduction of mineral fertilizers, seeds, their seal which are also checked in or-dinary operation to the soil on the optimum depth and a compacting of crops. Except economic effect of combination of transactions by the provided aggregates are obvious agro-nomical and cost efficiency: decrease in consolidation and a puddled condition of the soil that influences its fertility, complete use of soil moisture that guarantees amicable shoots and future harvest.
MATHEMATICAL MODELING OF THE CONTROLLED MOTION OF THE WHEELED MACHINE-TRACTOR UNIT
Authors: Poddubnyy V. I , Pavlyuk A. S , Poddubnaya M. L
Published: April 2022

A brief review of the systems of precise farming is given, problems of scientific and practical research are formulated to create a domestic system of accurate farming using autopilotation. The analysis of applied software used in the development and approbation of algorithms for controlling the movement of wheeled agricultural machines is carried out. The ideology of the development of mechatronic systems using the CAMeL-View application package is presented, a mechanical-mathematical model of the machine-tractor unit consisting of a wheeled tractor and a semi-mounted plow is described. The results of mathematical modeling of the movement of a machine-tractor unit at a speed of 2.5 m / s are presented using control based on the basic maneuvers of wheeled vehicles when the soil is processed to a depth of 0.24 m. The required slope angle of the tractor frame is defined as a linear combination of dependencies for changing the curvature of the trajectory, the direction of motion, the lateral displacement and the initial angle of rotation of the steered wheels. The analysis of the results allows to draw a conclusion about the rather good quality of the working movement of the arable unit, which indicates the efficiency of the proposed control algorithm. The program implementation of the control algorithm is proposed in the wheeled agricultural machines developed with the participation of authors of the electromechanical control system for the movement using satellite radio navigation systems GLONASS and GPS. With a real control of the movement of a wheeled agricultural machine, a significant deterioration in the quality of motion is caused by inaccurate determination of its current coordinates when using satellite GPS and GLONASS radio navigation systems. Accordingly, the level of lateral deviations of the working mechanisms of the agricultural machine will be higher than the motion obtained from the modeling results, using the proposed control algorithm. The final conclusion about the limits of applicability of the proposed control for various fieldwork will be made based on the results of field tests of the control system.
Reduction of aftereffect of machine units on the soil
Authors: Okunev G. A , Astaf'ev V. L , Kuznetsov N. A
Published: April 2022

Cultivation of crops is associated with multiple passes of machine units through the fields. The cumulative effect of soil compaction caused by repeated impacts of movers of machine units is considered as especially dangerous. The most intensive compaction process occurres in spring. The repeated passes of heavy machines and the compaction of surface and subsurface soil horizons lead to the decrease in yield potential of fields. The solving of compaction problem depends on the soil and climatic conditions, zonal cultivation technologies and crop harvesting, and on the machine system in operation. When forming the machine and tractor fleet of enterprises, the selection of general-purpose tractors serves as a basis. The least negative impact on the soil occurs when crawler tractors are used. The advantage of wheeled tractors is the possibility of their use for both field works and transport operations. But today the wheeled tractors are hardly used for transport operations because of their increased weight and power, which shows the necessity of use of such heavy crawler tractors as Ruslan and Challenger. Their use in combination with wheeled tractors of middle class allows to improve significantly the structure of machine and tractor fleet. The main power unit for farm enterprises with 1000 hectares of arable land is a general-purpose tractor of the 3rd traction class. The use of the HTZ-150K-09 tractor with 23.1R26 low-pressure tires with the air pressure of 80 kPa provides a permissible impact on the soil. The soil density in the surface layer reduces to 0.06 grams per cubic centimetre as compared to the use of 21.3R24 single wheels. This allows to put such tractor in operation for spring field works.
Potential productivity of the tractor
Authors: Kut'kov G. M
Published: April 2022

The agricultural tractor is designed to replace the live traction force with the main purpose - to increase the productivity of the farmer. But among the indicators of the tractor, characterizing its technical and technological level, there is no generalized performance indicator, reflecting the main property by which it would be possible to make a comparative evaluation of tractors of different models. The need to introduce an indicator of the productivity of the tractor has increased recently due to the significantly increased energy saturation. This increase in energy saturation is chaotic and is accompanied by a different mismatch in engine power and the weight of the tractor. There is a "surplus" power of the engine, which can not be used, because the traction force of the tractor is limited by its weight, and the speed of movement - by agrotechnical requirements. In these conditions, the introduction of the indicator of the tractor's performance in the number of indicators of the technical and technological level of the tractor acquires even greater urgency. The article defines the concept, substantiated and proposed a calculated indicator of agricultural tractor productivity - potential productivity. Potential productivity is proposed to understand the changeable design capacity of a tractor with a gun of such a width, at which its traction resistance is equal to the nominal design traction force of the tractor, and the speed of the machine-tractor unit is maximum for a given engine power, but does not exceed the speed established by the rules of agricultural technology. It is proposed to accept the potential performance of an agricultural tractor as one of its basic indicators of the technical and technological characteristics of the tractor in addition to the existing ones, and also to indicate in the list of technical parameters of the tractor.
Methodology for the development of agricultural modular aggregates
Authors: Dmitrenko A. I , Bur'yanov A. I , Goryachev Yu. O
Published: April 2022

The territories of agricultural regions of Russia are subdivided into subzones with different climatic and soil conditions, crop rotations and technologies, annual volumes and terms of work that determine the structure and composition of machine and tractor parks. In the designs of traditional technical means, as they were improved, the application of science and technology achievements was increased, ensuring an increase in the productivity of machines with a faster growth in their prices. An increase in the annual load of modern mobile energy facilities, which could significantly reduce the cost of their work, is limited by the agrotechnical timing of their implementation. Obviously, one of the ways to improve the efficiency of technical means is to combine the functions performed by different types of machines, for example, tractor and harvesting machines in one unit based on the power tool. Implementing the potential of such units will not always succeed. This is possible only if the periods of peak loads of machines for different purposes do not coincide, taking into account the specific functioning of the machine and tractor fleet of the agricultural enterprise of a certain type of activity in a particular region. At the same time, in addition to solving traditional tasks related to the development of constructive and technological circuits for mobile power equipment of a new generation with sets of replaceable adapter modules, a whole series of new problems arise, for the solution of which it is necessary to develop a set of methods for their implementation or methodology. The subject of the article's research is the methodology for the development of modular aggregates based on frame and replacement technological systems for agricultural enterprises taking into account the specifics of the current market and zonal conditions. The purpose of the study is to systematize and disclose methodological aspects of the development of modular aggregates for machine and tractor parks. The use of modular aggregates on the example of one model of an agricultural enterprise will ensure a reduction of capital investments in the machine and tractor fleet and operating costs for its maintenance by more than 17 and 14 % respectively, while a simultaneous increase in net discounted income by more than 53 %.
Automation of the test bench for experimental research of the local air cooler of the vehicle driver
Authors: Mikhaylov V. A , Klimova E. V
Published: April 2022

The question of automation of the test bench for research and selection on the basis of experimental data of rational supply of L air by a local water evaporator cooler of a vehicle driver (tractor, car, road-building machine) is considered. In the design of an automated test bench made in the form of an open wind tunnel, along with an auxiliary electric fan, an electric heater of the treated air, a local air cooler and a human heat simulator Qh, there are elements for measuring and controlling the quantities L, Qh, the temperature t of the treated air and th - the body surface simulator. The imple- mentation of the control system with active computing devices, where the leading role is played by the STH0024UY-v3 thermostat with a remote temperature sensor DS18B20, containing a microprocessor and a control electrical relay. s Such modules for t and th are assigned the main function of automated control of the stand, and the personal computer provides execution of the program of automated control in the «pulse - pause - pulse» mode, and also performs the auxiliary task of collecting and storing information about the data of the research results. As a result of the automation of the test bench, the time is shortened and the laboriousness of the study is eliminated. At control experimental check of functional qualities of the stand it is established that in the manual control mode the stabilization of indications th, t and L at a given level is associated with a great emotional and physical load of the operator, as he must almost continuously monitor them and to some extent intuitively influence changing their mechanisms. At the same time, a considerable time is wasted to achieve the necessary result. Automated control can almost completely free the operator from unnecessary manipulation, and only at certain intervals (not more than 120 seconds) he controls the readings of the instruments without interfering with the work of the stand. This removes his emotional and physical load, and due to the exclusion of unnecessary manipulation of controls, the experiment time will be shortened.
Analysis and development of the oil separator of the crank-case ventilation system of a highly-boosted diesel engine
Authors: Andriyanov S. M , Nikishin V. N , Kulikov A. S
Published: April 2022

Current problems, related to the development of the crankcase ventilation system for high-powered diesel engines, are considered. To avoid the occurrence of significant excess pressure in the crankcase, which negatively affects the tightness of the seals in engine, the crankcase gases are evacuated to the atmosphere. The main processes that take place in the ventilation system of the crankcase of the diesel engine are singled out and described, as well as the problems and ways of their solution. Information on the advantages and disadvantages of open and closed crankcase ventilation systems is presented. Considerable attention is paid to the main element of the crankcase ventilation system of any engine - oil separator. There is information on the analysis of existing crankcase ventilation systems and oil separators. The evaluation of the efficiency of the crankcase ventilation system is considered. There are criteria for: estimating the flow of oil directly into the crankcase ventilation system; relative oil content in crankcase gases; efficiency of the crankcase ventilation system. The installation for carrying out benchless motorless testing of open and closed crankcase ventilation systems is presented, the technique is described in detail on the results of tests of the patented pilot oil separator by specialists of STC PJSC «KAMAZ». There are data on motor tests of the open crankcase ventilation system with the patented oil separator of the modern diesel engine 8ChN 12/13. Experimental benchless motorless and motor studies confirmed the high efficiency of the crankcase ventilation system with an oil separator. It is established that as a result of bench motor tests of an open crankcase ventilation system with the use of an experimental oil separator, the limit of efficiency with the least efficiency (not lower than 97,5 %) is determined by the values of the consumption of crankcase gases 360 l/min.
Composite materials for impellers of the turbocharger of automotive engines
Authors: Netrusov A. N , Fomin V. M
Published: April 2022

The aim of this work is the search and selection of components of composite materials are fully meeting the requirements imposed to the materials of the impellers of the turbocharger. During the work modern components of the composites and their properties is described. The requirements to materials of impellers were formulated. Patent search was carried out to describe existing concepts of impellers made of composite materials. A possible production version of the impellers is described, revealed their advantages and disadvantages. In the course of patent studies have not traditional the advantages of using composites in the design of the turbocharger. Described the possibility of creating a rotor of the electric machine of the compressor impeller by weaving a copper wire. The main technology of manufacture of impellers is described. Given domestic and foreign manufacturers of polymer matrixes and fibers. The described physic-mechanical properties of randomly reinforced composite materials available on the market today. A comparative analysis of selected composite material most fully meets the requirements - polyamideimide filled carbon fiber. The use of continuous fibers in the impellers is an effective way to increase the strength of the latter. It is established that as a cheaper alternative to polyamideimide can be a carbon-containing material '^^11!" provided reinforcement of the wheel with continuous fibers. Cheap and widely used materials (filled polyamides, polycarbonates, epoxy resin, etc.) can be used in the manufacture of impellers in centrifugal blowers with manual or electric drive. Composites with carbon fiber in silicon carbide matrix (C-SiC) can act as an alternative to heat-resistant nickel alloys, of which currently produce the turbine wheel.
Investigation of viscoelastic state of soil under the influence of active surface of the tillage roller
Authors: Semenikhina Yu. A
Published: April 2022

Universal combined tillage machines combine several processing steps. The final soil cultivation operation is performed by soil-processing machine, which works on loosened soil. Uniform compaction of the subsurface layer is able to be created by soil cultivating rollers with an active working surface. The surface of the roller, which contains elastic elements, increases the vertical load. The shock loading, characterized by intensive impact on the soil, is considered preferable. The advantage of this roller construction is the integration of external loading and automatic tuning to a rational operating mode. The study of the process of soil compaction can be carried out by analogy with the process of soil compaction. The model of the system includes the mass of the working body m, the mass of the deformed soil volume M, the soil stiffness element C, and the soil viscosity element B. The volume of soil deformed by compression is a truncated cone with a height h. Initially, there are compressive stresses in the soil volume directly at the points of contact with the working body. Then instantly, large clods of soil are destroyed, and the surface particles are displaced (compacted). Further, the crushed soil particles transfer pressure to the neighboring ones, involving more and more particles with lateral expansion. As a result of compression deformation, a compacted subsurface layer of the required density is formed. The proposed model can serve as a first approximation for further, more detailed and expanded studies of the stress-strain state of the soil with the possibility of determining the dependencies of the structural parameters and operating conditions of the soil-working compactor.
Characteristics of external influences on the operation of machine-tractor units
Authors: Kambulov S. I , Rykov V. B , Bozhko I. V , Kolesnik V. V
Published: April 2022

The most significant feature of the operation of agricultural machine-tractor aggregates is the random nature of external influences, which determines its output indices. The main task of the theory of complex systems should be considered the development of methods that allow on the basis of their functioning to obtain the characteristics of individual elements and analyze the interaction between these elements and the external environment, to determine the characteristics of the system as a whole. The purpose of the study is to analyze the characteristics of external influences as a reaction to the operation of machine-tractor units. When solving many problems of agricultural mechanics (researching technological and production processes, building models and synthesizing the parameters of working organs and aggregates), it is necessary to take into account the external factors that determine the main regularities of various processes. The process of operation of the unit can be represented in the form of a set of states - vectors of output quantities: agrotechnical, technological, kinematic, energy-power and so on. The role of input quantities is played by external conditions and control actions, which also have a certain set of states. External influences on the unit are technological, operational and constructive factors, the number of which include soil resistance, the surface profile of the field, the physical and mechanical properties of the material being processed (soil density, soil moisture, etc.), the technical condition of the machine working bodies, and the depth of processing. As the speed of motion increases, the correlation between the sections of the random function decreases. As the speed of motion increases, the spectral density decreases, and its maximum value shifts towards higher frequencies; spread of the values of random function with respect to the mathematical expectation increases with increasing aggregate speed; by correlation functions and spectral densities, it is possible to establish the main parameters of random processes, variances, the mean square deviations prevailing in the frequency process and the corresponding periods, the dispersion distributions over frequencies that are necessary to establish the parameters of the output indicators characterizing the level of functioning of agricultural machine-tractor aggregates.
The influence of morphological characteristics of winter wheat plants on the choice of operating modes of combing header
Authors: Bur'yanov M. A , Bur'yanov A. I , Chervyakov I. V , Kostylenko O. A
Published: April 2022

The purpose of the research is to determine the degree of influence of morphological features: the length of plants, their stems, ears of winter wheat grown in the southern subzone of the Rostov Region, and the choice of operating modes for combing headers. The problems arise from the discrepancy between the parameters and operating modes of the combing devices for the characteristics of the harvested grain, and also because of the lack of knowledge of the physico-mechanical characteristics of the crop plants currently cultivated. When harvesting with streaks, it is necessary that only the ear of the plant gets into the working zone, the parameters of which are determined by the diameter of the combing drum, the gap between it and the fairing, their mutual arrangement, and the position of the header relative to the field surface. Compliance with this condition is necessary, but not sufficient for cleaning with a streak without loss of grain. When modeling on the mathematical model of the process of combing grain crops realized by a combing header in a specific field, knowledge of more than ten physico-mechanical characteristics of the harvested plants is required. Data on the characteristics of plants of winter wheat, cultivated in the conditions of the south of Russia, was accumulated by us for six years. The data on the non-uniformity of plant characteristics of five varieties of winter wheat are obtained. Measurements were carried out within the field to be cleaned, individual plots and grown in one bush. Geometric characteristics of plants, such as their height, length of stem and ear can be estimated with a certain degree of accuracy with a small number of measurements and visually, with the selection of the most different sites on the harvested massif. This article illustrates the influence of the geometric parameters of the plants of the crop being harvested on the quality of the process being performed and the possibility of controlling it by regulating the operating modes and controlling them.
Investigations of the physical properties of camelina oil mixtures for hydraulic systems of agricultural machinery
Authors: Zartdinov F. F , Zartdinova F. F , Khokhlov A. L , Glushchenko A. A , Salakhutdinov I. R
Published: April 2022

The article considers the use of oils of vegetable origin alternative to mineral and synthetic oil products as a working fluid for hydraulic systems of agricultural machinery. When choosing vegetable oil, the use of camelina oil as a more affordable and economically cheap raw material is most appropriate. The main disadvantages of vegetable oils include low thermal and oxidative stability and unsatisfactory low-temperature properties. Therefore, the use of vegetable oils in hydraulic systems is possible only in the form of mixtures with mineral oil. To study the possibility of using vegetable-mineral oil as a working fluid for hydraulic systems of agricultural machinery, laboratory studies of the physical properties of camelina oil mixtures were carried out. The studies included the determination of the relationship between the kinematic viscosity and the density of the camelina oil mixtures from the temperature and were carried out in various proportions of the mineral hydraulic oil - multigrade oil hydraulic thickened (hydraulic oil - GM) and camelina oil (RyzhM) - 100 % GM, 90 % GM - 10 % RyzhM, 75 % GM - 25 % RyzhM, 50 % GM -50 % RyzhM, 25 % GM - 75 % RyzhM, 10 % GM - 90 % RyzhM, 100 % RyzhM. Determination of the physical properties of the camelina oil mixtures was carried out on a cryo-thermostat with viscosimetric LOIPLT-912, using an ANT-2 hydrometer and capillary viscosimeter VPZh^f, VPZh-2 in accordance with GOST R ISO 3675-2007 and GOST 33-2000 (ISO 3104-94) respectively. Based on the results obtained, it was found that red-and-oil mixtures with a ratio 90 % GM - 10 % RyzhM и 75 % GM - 25 % RyzhM according to viscosity-temperature properties and density can be used as substitutes for merchant mineral hydraulic oil GM. The results of the laboratory tests allow us to display the dynamics of the change in viscosity-temperature and density properties of red-and-oil mixtures of various concentrations.
Energy analysis of dual-flow hydromechanical gears
Authors: Sharipov V. M , Shchetinin Yu. S , Gaev S. V , Troshkin O. V
Published: April 2022

Two-flow hydromechanical transmissions are becoming increasingly common in the construction of modern land transport and traction machines (tractors, automobile and high-speed crawler vehicles). This is mainly due to the desire to increase the efficiency of transmission. In order to select a dual-flow hydromechanical transmission scheme in relation to specific operating conditions, it is necessary to know the advantages and disadvantages of various schemes, their potential capabilities. The evaluation of the operation of each circuit can be made on the basis of their kinematic, power, and energy analysis. The results of the kinematic and force analysis of two-flow hydromechanical gears were previously developed by the authors of this article. In energy analysis, the following estimated parameters were used to compare the performance of the transmission: г|ГМП - efficiency of transmission; РМ - power factor in the mechanical branch of the transmission; РН - power factor on the pump wheel of the torque converter; РТ - the power factor on the turbine wheel of the torque converter. The paper considers 12 schemes of two-flow hydrome-chanical gears with a differential link at the input and output with mixed gear coupling, the results of their energy analysis are given. For each of the schemes considered, analytical dependencies of the estimated parameters on the internal parameters of the hydromechanical transmission were obtained, which were used as the characteristic k of the planetary gear set, the power transfer ratio йгт of the torque converter, and the kinematic gear ratio игмп of the hydromechanical transmission. The results of calculations performed on a computer using the external characteristic of a specific torque converter are obtained and presented in graphical form. The obtained results can be used in developing recommendations for the choice of a two-flow hydromechanical transmission scheme.
Evaluation of design and production of ICE
Authors: Kochenov V. A , Sakharov A. N , Kazakov S. S , Zhamalov R. R , Goeva V. V , Grishin N. E , Grunin K. E
Published: April 2022

It is proposed the analysis of design and production of the internal combustion engine friction units in durability and wear resistance. With a variety and dispersion of factors that determine the durability and wear resistance of the internal combustion tribome, the change in wear and wear intensity during the operation has a pronounced natural character. Evaluation of the design and manufacture of ICE is based on a comparison of the indices of durability and wear resistance of the actual and theoretical tribo-conjugation. Manufacturing tolerances reflect the potential of technical production capabilities. The design coefficient shows the correspondence of the geometry of the newly manufactured friction surface to its optimal, attained parameters. The experimental data are taken from the results of road and accelerated tests of the engines GAZ and ZMZ. Reducing wear in the run-in, design and manufacturing errors is due to improved design and lower manufacturing tolerances. Reducing the intensity of wear and increasing the operating time of parts is associated with the improvement of the material of rubbing surfaces and lubricant, and improvement of roads. The change in the design coefficient indicates that there are no pronounced trends in the design and production of the geometric parameters of the tribo-conjugate. Domestic automotive industry and engine building focused mainly on the domestic market. Design and production took into account the high demand for machines, the sparseness of the larger territory of the country, i.e. low concentration of machines in these areas and the difficulty of organizing a company service that is dependent on the number of machines in the service area. As a result, many vehicles have become uncompetitive in terms of technical characteristics, in price and reliability. The course for the modernization of the production of engines presents increased requirements for design, consisting in the full use of the technical capabilities of manufacturing and determining the prospects for their further growth.
Dependence of the agrotech-nical clearance under the front axle of a cotton tractor with a wheel arrangement 4K4a on the dimensions of the pivot pin, the size of the tires of the steered wheels and the angles of their installation
Authors: Kambarov B. A
Published: April 2022

At present, the concept of the transition of cotton energy to a four-wheeled power plant is being worked out in the republic. And it has, in comparison with the existing one, an additional potential for increasing productivity due to increasing the ranks of agricultural machinery. Cotton refers to high-growth technical crops, as at the stage of maximum biological development plants reach a height of 800...1250 mm. Minimal traumatization of the above-ground part of the plants during the processing of row spacing and loss of harvest during harvesting is largely due to the increased agrotechnical clearance of cotton-growing tractors. The modern cotton tractor has a scheme of propulsors with axle configuration of 3K2 and clearance of 820...830 mm under tubes of shafts of rear axles, due to the installation of additional final gears. The front steer axle is single-wheeled, it does not prevent the safe passage of plants under the tractor's framework. When developing a four-wheeled cotton tractor, a major problem is the provision of the required agro-technical clearance under the tube of the front axle. Preliminary studies have established that it is possible to change the agrotechnical clearance under the portal structure of the front axle by changing the length of the pivots of the pivot pins to the dimensions that provide the four-wheeled tractor with satisfactory flotation above the row of cotton. At the same time, it is necessary to take into account the known effect of the linear and angular dimensions of the front axle on the kinematic characteristics of the steering and the operation of the propulsors, in connection with which the analytical interrelation of the agrotechnical clearance under the front axle of the tractor with axle configuration 4K4a, the dimensions of the pivots of pivot pins, the dimensions of the steered wheels and the angles of their settings, allowing to calculate the amount of agrotechnical clearance under the beam of the front axle for different combinations of arguments that are included in this dependence. For example, it is established that with the length of the pivot shaft of the experimental front driving axle of 435 mm and the installation of 11.2-20, 11.2R20 and 11.2R24 tires, an agro technical clearance is provided within 826...877 mm, which meets the requirements of the technical specification for the cotton tractor.
Optimization of traction characteristics of agricultural tractors
Authors: Samsonov V. A , Lachuga Yu. F
Published: April 2022

The productivity of the machine-tractor unit depends on the energy saturation of the tractor. It is assumed that the optimum traction characteristic corresponds to the minimum operating weight of the tractor and its maximum energy saturation, at which the maximum productivity of the machine and tractor unit is achieved with the lowest fuel consumption and compliance with restrictions on tractive effort, slippage and theoretical speed. As a criterion for determining the maximum energy saturation, the maximum efficiency coefficient is adopted with maximum tractive power and maximum tractive efficiency. Calculation of the optimal traction characteristics is an actual task of the theory of the tractor. The purpose of the study is to develop a methodology and algorithms for calculating the indicators of the optimal traction characteristics of the tractor when the engine speed of the crankshaft is changed. The objects of research are wheeled and caterpillar tractors of general purpose. Input data: engine and tractor performance indicators; coefficients that characterize the traction and coupling properties of the tractor; the tractor power balance equation; slipping functions; the dependence of the fuel consumption of the engine and its torque on the speed of the crankshaft. The method of research is the calculation using the basic formulas of the theory of the tractor when the speed of the crankshaft is changed by one rotation. Taking into account the accepted values of the nominal engine speed and the torque adaptive factor, the gear ratio is calculated. The calculation procedure for the optimum traction characteristic is developed for tractors with a minimum operating weight, calculated taking into account the nominal tractive effort and the coefficients of using the gravity of the tractors. The maximum energy saturation for each type and traction class of the tractor is determined by calculating the tractive characteristic of the transmission, at which the maximum efficiency factor, traction power and traction efficiency are reached. The main conclusion: the optimum traction characteristic corresponds to the minimum operating weight of the tractor and its maximum energy saturation.
Simulation of combustion process in the forced transport diesel engine with the prescribed law of mixture formation
Authors: Kamaltdinov V. G , Markov V. A , Lysov I. O , Popov A. E , Smolij A. E
Published: April 2022

There was developed a new single-zone model of the fuel combustion process, based on the equations of chemical kinetics, which takes into account in more detail the features of the internal chamber processes of internal combustion engines. The combustion process is considered as a set of successive oxidation reactions to carbon dioxide and water of groups of active fuel molecules proceeding according to the Arrhenius law. The number of active molecules of fuel entering into the reaction depends on the total number of fuel molecules, the current mixture temperature and the conditional activation energy, varying depending on the fraction of burned fuel. The conditional duration of oxidation of this group of active molecules is assumed to depend not only on the total number of fuel molecules, but also on the volume of the combustion chamber, the number of oxygen molecules, the number of molecules of inert components and turbulence inside the combustion chamber. The heat released during the oxidation of each group of active fuel molecules is determined through the lower heat of combustion of the fuel and is expended to increase the temperature and pressure of the mixture in the combustion zone. At each step of the calculation, the number of molecules of all substances is corrected as a result of fuel burn-out. A special feature of the model is the introduction of a new parameter that takes into account the time factor at the molecular level, the conventional duration of the oxidation reaction of the active molecules of the fuel. A new mathematical model is used as the basis for the algorithm for the developed program for calculating the operating cycle of an accelerated diesel engine with a prescribed law of mixture formation. Calculations of the influence of the temperature of the fresh charge after the charge air cooler on the duty cycle of the forced diesel in the range from 360 to 430 K are performed. According to the results of the calculation, it is established that the best indicator characteristics of the working cycle are reached at a temperature of 360 K. Indicator diagrams of pressure in the cylinder and the laws of heat generation, obtained by calculation correspond with known experimental data.
Increase in the level of functioning of agricultural tillage machines by justifying the parameters of the column of the working body
Authors: Kambulov S. I , Rykov V. B , Bozhko I. V , Kolesnik V. V
Published: April 2022

The working bodies of tillers perform the most important role from the point of view of the technological process of tillage, as they provide all the parameters of its application. The purpose of the study is the justification of the parameters of the column of the working body of the tiller machine. The traction resistance as the main parameter of the working element is affected by the shape of lateral profile and cross-section of the column. In general, in the cross section, the columns of the working bodies can have: a plane with rectilinear boundaries, a plane with curvilinear convex boundaries, or a plane with curvilinear concave boundaries. The compacted core of the soil in front of the stand is not formed when the grinding angle is not more than 50°. In all other cases, such a nucleus is formed even at asymmetric sharpening angles. Consequently, the necessary condition for the shape of the cross section of the column should be the observance of the value of mentioned angle. The cross-section of the column (Folium of Descartes) meets the requirements imposed on it, as the sharpening angle does not exceed 50°, which does not contribute to the formation of the compaction core, and the boundary has the shape of a convex line, which ensures a minimum absolute speed, on soil movement. The column of the working body of the tiller machine should have the shape of a lateral profile close to the logarithmic curve, which reduces the energy intensity of the process by 20 ... 45 %, and in the cross section of the column there must be a plane bounded by arcs of the ellipse and tangent to these arcs drawn so that the angle at the top of the ellipse did not exceed 50°. This reduces the traction resistance of the column by 40 ... 52 %.
Over-view of robotic grippers for physical manipulation with agricultural products
Authors: Vu D.K - , Solenaya O. Ya , Ronzhin A. L
Published: April 2022

An overview of agro-grips used to control weeds and harvesting is presented. The relevance of the study is justified by the possibility of improving the quality of fresh fruit and vegetable products, reducing production costs, decreasing the labor shortage by developing and introducing agricultural robots. The classification of the grippers, which are installed on robotic agricultural machines for manipulating fruits, weeds and other objects, is compiled. There are 22 types of grip depending on 6 selected criteria: drive type, the presence of the drive in the grip, the number of fingers, the type of grip movement, the type of mechanism, the type of sensors. In this classification, we mainly consider the characteristics of the gripper, which is installed at the end of the manipulator and is responsible for physical contact with the object. Therefore, the main attention is paid to problems requiring direct capture of objects by the agro robot. The problems of direct spraying of weeds or pruning of branches and leaves, in which manipulators also participate, but the objects of influence are not captured by the robot are mentioned. Examples of existing agricultural research robots equipped with combined grippers according to the proposed classification, referring to different types: vacuum gripper with a video camera for capturing tomatoes, six-finger pneumatic gripper with a video camera, a two-fingered gripper with pressure and collision sensors for picking up an apple, three-fingered capture with a video camera for capturing citrus fruits and others are shown. Further work will be devoted to the study of the problems of physical interaction of agro robots with processed objects, differing in weight, density, geometry, surface roughness and other parameters. The issue of joint interaction of a group of heterogeneous terrestrial and airborne robots in the performance of the target agrarian task in an autonomous mission will also be investigated.
Efficiency of surface treatment of soil by a stubble multifunctional cultivator
Authors: Maslov G. G , Yudina E. M , Zhurij I. A
Published: April 2022

The effective application of the stubble cultivator on surface tillage is justified simultaneously with the introduction of solid mineral fertilizers. The atomization of the soil in comparison with the disk tools decreases in 1,5...2 times. Using the example of the proposed multifunctional stubble cultivator with the device for simultaneous application of mineral fertilizers, the possibility of using the cost and loss function (the cost of carrying out the amount of work and the loss of the future crop due to a violation of the optimal duration of work) is proved to optimize the duration of work. A block diagram of the algorithm for optimizing the parameters and operating conditions of a multifunctional stubble cultivator is presented based on the criterion of the optimal value of the traction factor of a given tractor, taking into account its traction characteristics and the dependence of the coefficient of the resistivity of the cultivator on the working speed of movement, the depth of processing and the specific material consumption, with consideration of the mass of fertilizers applied. In the objective function of optimizing the duration of the work performed, the cost of the cost includes the operating costs for the specified unit for the planned scope of work. With an increase in the duration of these works, costs are reduced, and the cost of future crop losses, on the contrary, increases. The sum of costs and losses has an extremum, which determines the optimality of the solution. The dependence of the cost of losses of the future corn grain crop on the duration, the amount of work, the purchase price of the harvested crop and the intensity of losses for each day of the violation of the optimal period of stubble cultivation of the soil with simultaneous application of mineral fertilizers is given. With the help of the obtained cost and loss function, the optimum duration of stubble cultivation of the soil was established with the simultaneous introduction of solid mineral fertilizers using the example of the machine-tractor unit as part of the MTZ-1221 tractor and the stubble cultivator KSU-3 with the device for simultaneous application of solid mineral fertilizers.