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Smoothness of movement of agricultural units is one of the important operational indicators of their work which is estimated on influence of fluctuations (translational vertical, cross, angular longitudinal, etc.) The article presents the method and results of experimental assessment of the smoothness of the movement of the bridge agricultural unit, which moves in the footsteps of a constant technological track. Studies of the smoothness of the bridge unit showed that the graphs of normalized correlation functions of vertical oscillations of the bridge agricultural tool developed by us in its motion in the wake of a constant technological track is characterized by a function containing along with random components harmonic, which are expressed by attenuating periodic oscillations. The frequency spectrum of oscillations of the agricultural tool core is concentrated in the range from 0 to 20 s–1, which agrees with the frequency range 0…0.3 cm−1 in which the variances of oscillations of the irregularities of the profile of the traces of the technological track are concentrated. The length of the correlation connection is approximately 0.25 s, which is equal to 0.25 m at the speed of the agricultural tool within 1.0 m / s.The obtained result is explained by the fact that the main spectrum of oscillations of the profile irregularities has a periodicity that corresponds to the step of ground engagement of the tires of the wheels of the agricultural tool. The research confirmed the effectiveness of the method of estimating the intensity of vertical oscillations of an agricultural unit by a measuring and registration complex based on a tablet computer with Android operating system with built-in accelerometer sensors and Accelerometer Meter application.

A promising direction for further development of agriculture not only in Ukraine but also in the world is the introduction of innovative technologies, to which we should include the track system of agriculture. The movement of transport and energy vehicles on the aligned compacted trace of the constant technological track causes undesirable and uncharacteristic vibrations for agricultural machinery. The latter are due to the influence of the microprofile of the constant technological track, which has a significant negative impact on the degree of comfort and efficiency of the operator, operational and technological indicators, reliability and smoothness of machines. The method and results of experimental automated estimation of the microprofile of irregularities of traces of the constant technological track are presented in the article. Experimental studies of the microprofile of irregularities of the traces of the constant technological track have shown that the standard deviation of the irregularities of the profile is ± 0.84 According to their internal structure, the inequalities of the profile of traces of the constant technological track are characterized by a function that contains, along with random components, the harmonic ones, which are expressed by attenuating periodic oscillations of the normalized correlation function. The main share of variances of oscillations of the irregularities of the profile of the traces of the technological track is concentrated in the frequency range from 0… 0.3 cm − 1. The generator of formation of irregularities of a longitudinal profile of soil traces of a constant technological track are parameters of ground hooks of tires of wheels of the cars moving on it.This is confirmed by the fact that the length of the correlation of the ordinates of the irregularities of the profile of the traces of a constant technological track in the conditions of tests of the bridge agricultural tool of the new design is about 0.18 m, which corresponds to the pitch of its tires.

Many years of research have shown that when working on a tractor on soft soils, characteristic of almost most farmers. operations, there is a deep immersion of the wheel hooks in the soil layer. Immersed in the ground, the hooks press it in the horizontal direction opposite to the movement of the tractor. As a result, there is a decrease in the translational speed of its movement. Research in this direction, taking into account the conditions of movement of wide-track agricultural equipment in the wake of a constant technological track, has been conducted by scientists is extremely insufficient. And in considering the problem of developing the scientific basis for the use of a bridge tractor, some scientists believe [13] that the issues of their theory and technological properties require further development and development. One of the ways to reduce the energy intensity of production processes in agriculture is the transition to track and bridge agriculture using wide-track (portal) vehicles (or bridge tractors), which are specially adapted for this purpose. Since their movement in the footsteps of a constant technological track is characterized by both an increase in traction and coupling qualities, and a significant decrease in resistance to their rolling. Because of this, bridge tractors are able to develop a higher level of traction and energy in contrast to a traditional tractor, which moves on agricultural land. agrophone. The issue of determining the required level of energy saturation of wide-gauge (portal) vehicles becomes relevant in order to create a system of their aggregation and practical use. As a result of the conducted researches it is established that the required level of energy saturation of the bridge tractor should be at the level of 23.5 kW / t. Under conditions of sufficient adhesion of the engines of a wide-track agricultural vehicle with the supporting surface of the soil trace of a constant technological track allows it to develop traction at the level of 6.37 kN per ton of its operating weight.

The article exposes the results of the mathematical simulation of the agricultural bridge equipment functioning. The mathematical models describing the functioning of the agricultural bridge equipment were checked for adequacy by comparing the theoretical and experimental amplitude-frequency characteristics of the oscillations of its heading angle and lateral displacement. It was established by the result of investigated characteristics’ quantitative assessment that a satisfactory coincidence of the theoretical and experimental results, as well as a positive result of checking the adequacy of the mathematical models of the vertical and the horizontal oscillations of the agricultural equipment indicate a possibility of their further use for solving scientific and practical problems.

The use of centrifugal disk fertilizer spreaders, the axes of which are set obliquely, in the technological process of mineral fertilizers provides an increase indicators characterizing the spreading of technological material in the direction of its scattering, at a greater distance than fertilizer spreaders with vertical axis of rotation. Thus, the hypothesis of the possibility of increasing the working width of the machine for applying mineral fertilizers by equipping such machines with centrifugal disk fertilizer spreaders, the axes of which are set at an angle, is confirmed. Experimental research was conducted using the developed methods and current state standards, regression analysis, statistical methods of processing research results, standard and specially designed experimental equipment. The calculations were performed using the software environment Microsoft Office Excel 2007. As a result of experimental researches it is established that the centrifugal disk fertilizer spreaders which axis is placed inclined, reliably provides performance of technological process at change of frequency of rotation of its disk from 600 to 1000 rpm and changing the angle of installation of the disk to the horizon from 0o to 30o. For all studied kinematic modes of operation of the new working body, the effective scattering range of mineral fertilizers and the distance from it to the tray with the maximum share of the mass of sown fertilizer increase most rapidly with increasing disk angle to the horizontal plane from 0o to 10o, and least when changing the angle within 20o - 30o. The best indicators of fertilizer application both in terms of working width of capture and in terms of uneven application of fertilizers are provided at the angle of inclination of the disk of the new working body to the horizontal plane within 25o-30o.

Goal. To study the correlation between the indicators of physicomechanical properties of the soil trace of the constant technological track and their influence on the traction properties of the bridge agricultural tool. Methods. Experimental studies were conducted according to generally accepted and developed methods and involved the use of modern control and measuring equipment. Results. As the dimensionless criterion for assessing the rolling of the wheel of a specialized wide-track agricultural tool, taking into account its tangential force and resistance, the coefficient fk of its rolling resistance is taken in the work. Based on experimental researches and processing of the received data on the personal computer analytical expressions of regressive dependences of the coefficient of rolling resistance of wheels on humidity, hardness, and density of a trace of a constant technological track are created and their graphic charts are constructed. The results of experimental studies have shown that the physicomechanical properties of the soil in the traces of a constant technological track and the coefficient of rolling resistance of agricultural tools have a fairly high correlation. Conclusions. As a result of the carried out researches, it is established that the physicomechanical properties of a soil trace of a constant technological track essentially influence energy expenses on overcoming forces of resistance to the rolling of wheels of agricultural tools. With an increase in the soil of moisture of the permanent technological track from 10 to 45%, the coefficient of rolling resistance increases from 0.06 to 0.1 (66%). And since the charges of power to overcome the forces of resistance during motion are proportional to the value of fk, the same percentage increases in energy consumption. With increasing hardness from 2.8 to 4.5 MPa and density from 1.3 to 1.6 g·cm–3 of the soil trace, the rolling resistance coefficient of the wheels of the agricultural tool decreases from 0.1 to 0.06. Also, with the increase in the hardness of the soil trace of the constant technological track from 2.5 to 4.0 MPa, the value of the coefficient of volumetric crushing of the soil — from 4.0 to 45.0 MPa. With the further increase in the hardness of the soil trace, the coefficient of volumetric shrinkage of the soil almost does not increase. To reduce the coefficient of rolling resistance of the wheels when moving on the ground track of a constant technological track, it is necessary to form it as an undeformed bearing surface, then the rolling resistance has the least value.

Controlled traffic farming allows to minimize traffic-induced soil compaction by a permanent separation of the crop zone from the traffic lanes used by wide span tractors. The Authors developed an agricultural wide span vehicle equipped with a skid equipment for turning and an automatic driving system prototype based on a laser beam. The aim of this work was to study the kinematic conditions that control the steering of this machine. Furthermore, the accuracy and the maximum delay time of the signal transmission by the automatic driving system of the set-up was also assessed. In comparison with crawler tractors, the turning of the agricultural wide span vehicle needs a smaller difference in the moments applied to its right- and left-side wheels. For the predetermined accuracy of the beam position relative to the plant rows, ±ds = ±0.025 m, the accuracy of the direction of the laser beam at a distance S=200 m should not be more than ±0.07° and ±0.0014°, considering a run length of 1000 m. Furthermore, at a speed V=2.5 m s–1 a trajectory deviation φ≤5° requires a topmost delay time of the control signal of Δtmax=0.11 s is required.

Recently, rapid development of controlled traffic farming convincingly demonstrates the broad prospects of using the wide span tractor-based field machines throughout the world. The issue at hand lies in the fact that having a wide span tractor-based machine with steering-wheel system moving along the tracks of a constant technological track is not a rational option. According to the concept of bridge and rutting agriculture, it is advisable to subordinate the automated means of mechanization to the principles of the functioning of the coordinate transport system in which machines can move only in two mutually perpendicular directions and for implementation of which the field must have strictly defined dimensions. Therefore, a method of power steering similar to a crawler tractor (track-type tractor) can be more efficient in the automatic driving of bridge means of mechanization within the coordinate-transport system than a kinematic control. Furthermore, methodology utilized for selection of design schemes, parameters and operating modes of machine-tractor aggregates can not be used for study of dynamics of the wide span tractor-based field machine. Theoretical study is based on theoretical mechanics, theory of mobile energy facilities, statistical dynamics and theory of automatic control of linear dynamical systems with reproduction of statistically random control and disturbing input effects. Purpose of the research lies in development of a dynamic model of plane parallel motion in the horizontal plane of a wide span tractor-based field machine unit using a power (onboard) method of control, which would allow investigation of impacts of the control parameters and disturbing influences on the controllability and stability of its motion. Mathematical models have been developed and new regularities of the straightforward parallel movement of the wide span tractor-based field machine unit for controlled traffic farming have been obtained. The results obtained allow the validation of new schemes, design parameters and modes of operation with acceptable controllability and stability of movement in the horizontal plane with a power control method of the chassis.

The purpose of this study is to improve the technical and economic performance of the enhanced two-machine seeder based on the wheel-type tractor of traction class 1.4. Experimental research is based on the general provisions of the standard methodology for operational and technological evaluation of the operation of machine-tractor units in the field. Processing of results from experimental study was carried out by means of developed programs on a PC. Results obtained from field experiments testing the aggregate consisting of two-machine seeder of traction class 1.4, two SZ-3.6 seeders and a semi-mounted coupler indicate its high operational and technological efficiency in comparison to both single-machine and similar two-machine units as part of a conventional trailer hitch. Although it shows an increase in specific time losses at headland of up to 5%, due to the wider working width, utilization of a new two-machine unit on the basis of a semi-mounted coupling in comparison with a single-machine unit allows increasing the productivity of the work by 1.96 and reduction of fuel consumption by 20%. In order to ensure that two-machine unit will perform turning on headland in the optimal mode, it is necessary to equip it with a special automatic device that would change the speed of movement in compliance with the angular speed of tractor‘s steering wheels according to the developed algorithm.

The purpose. To heighten smoothness of course of specialized wide-track agricultural vehicles by justification of scheme, mechanically-technological and other parameters, and also performances of long- edged profile of unevenness of agricultural background in traces of shaped technological track. Methods. Original positions of theoretical mechanics, statistical dynamics of the theory of autocontrol of linear dynamic systems and theory of tractor, creation of programs and calculations for PC are used. Results. New mathematical models are elaborated of operation of the created specialized wide-track agricultural vehicle for track system of farming agriculture in vertical plane. Their use allows justifying demands to performances of long-edged profile of unevenness of agricultural background in traces of technological track, raising smoothness of a course in view of kinematic and power correlations of its power and technological part. Conclusions. Smoothness of course of specialized wide-track agricultural vehicle as dynamic system, which moves on traces of the fixed technological track, essentially depends on structure of its long-edged profile, rigidness of tires of anvil wheels (which value can be influenced in the fixed limits by changing air pressure). Dynamics of vertical vacillating of technological part is caused by its operation mass.