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The work is devoted to the analysis of the transmission of a special vehicle (SV) for moving on various surfaces, in particular on stepped ones, designed for people with disabilities. Based on the analysis of various vehicles for the movement of people with disabilities, a model of a SV was created. The main difference of proposed SV is the possibility of using the movement of the passenger՚s center of mass relative to the chassis of a SV for stabilization of the movement. A kinematic scheme of the SV transmission which includes the planetary reducer was created. The reducer provides movement of SV at various modes. Also SV transmission was modeled in the Solidworks software. The analysis of the performance of this transmission when moving a SV on various surfaces was made on base of created 3D-model. Based on the analysis, the efficiency of the transmission of a SV was proved both when moving on a straight surface, and in walking mode when overcoming steps.

The system of special vehicle (SV) motion stabilization during moving on a straight surface is modeled on the base of dynamic equations of the mathematical model. The movement is stabilized by using a PID controller, the angular displacement of the mass is selected to ensure a given speed of movement, and the deflection angle is stabilized by controlling the engine torque.

Problem of loading and unloading of tracked vehicles on a rail flatcar can origin during the transportation of construction machinery, for example in case of reconstruction works near railways when using of cranes is impossible. Current solutions are based on use of ramps connected to a rail flatcar. These ramps are lowered on rails for moving out of a vehicle. At this protection of rails and railway elements during vehicle turning is provided by preliminary stacking of sleepers and automotive rubber tires on place for vehicle movement. This article describes automated method and appropriate mechanism for loading and unloading of self-propelled tracked machines on a rail flatcar. This method provides reduced labor intensity and process duration by exception of hand operations and also avoidance of damages of railway elements.

We present the results of observations of variations in the mid-latitude ionospheric parameters and physical processes in the geospace during March 20, 2015 partial solar eclipse over Kharkiv (49.60° N, 36.30° E) where the eclipse magnitude was about 0.54. The Kharkiv incoherent scatter (IS) radar and digital ionosonde were used for ionospheric observations and estimations of the parameters of the thermal and dynamical processes. At the time of the maximum obscuration of the Sun's area, an increase in the ionospheric F2 peak height by about 40 km was observed. At the same time, the electron density at altitudes of 190 and 210 km decreased by approximately 18.5 and 16.5%, respectively. During the eclipse, a decrease in the electron temperature and apparent changes in the vertical plasma drift velocity were observed. The observations and analysis have shown that the solar eclipse led to significant restructuring of the thermal and dynamic state of the ionospheric plasma over Kharkiv.

The equipment and methodical characteristics of determining the vertical component of the ionospheric plasma motion velocity Vz based on an incoherent scatter radar of Institute of Ionosphere, National Academy of Sciences and Ministry of Education and Science of Ukraine (Kharkiv), which is the only radar of such type in Central Europe, are described. Based on the radar data, the patterns of altitude and diurnal variations in Vz near the maximum of solar cycle 24 for the typical geophysical conditions (around the summer and winter solstices, the spring and fall equinoxes) at low geomagnetic activity and the specifics of these changes during ionospheric storms are presented. The results of modeling of the dynamic processes in ionospheric plasma under the conditions of the undisturbed ionosphere, including the determination of altitudetime variations in the thermospheric wind velocity, are presented. It has been established that this velocity can significantly differ from the thermospheric wind velocity calculated by the known empirical global models. This difference is likely related to the regional features of thermospheric wind that are not shown in the global models.

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.

The article deals with the problem of noise reduction of vehicles. Noise pollution is an important environmental problem. Currently, the level of urban traffic noise varies from 70 to 95 dBA, which significantly exceeds the current sanitary standards. The main source of vehicle noise is the engine and its systems. In the engine noise, the component caused by the combustion process and mechanical component are mentioned. The next most important source of noise are transmission units. In them, noise is generated by gears, bearings and fast rotating shafts. Tires of a moving vehicle are one of the main sources of vibration and noise at high speeds (from 80-90 km / h). Sources of noise of aerohydrodynamic origin are stationary or nonstationary processes in gases. One of the most intense aerodynamic sources of noise is vortex formation in flowing parts of mechanisms. When the vehicle is moving in the air stream, it is a source of turbulence, so noise increases with increasing speed. The authors carried out a number of experimental studies of the noise emission of individual units of a automobile - engine, gearbox, cardan gear, differential, exhaust system. Taking into account the results of experimental studies, a technique is proposed for the probabilistic calculation of the vehicle noise. A mathematical model is developed for calculating the expected noise in the passenger compartment of passenger automobiles, which allows obtaining not only the mathematical expectation of noise levels from each unit and its spectral components, but also their dispersion. On the basis of the model, a program has been created that makes it possible to obtain the spectral noise components from each of the sources in one-third octave bands with an estimate of the probable range of their values (confidence intervals) even at the design stage of the vehicle, which allows us, at the design stage, to lay down the necessary characteristics of the noise emission of aggregates and the automobile as a whole. The created technique can be successfully used also for an estimation of characteristics of noise emission of other vehicles - cargo and other automobiles, buses, wheeled and caterpillar tractors, agricultural machines.

The article presents an analysis of the results of the experimental study, during which the load was determined for the gear wheel shaft of the rear-axle gearbox of the all-terrain vehicle transmission on ultra-low pressure tires TREKOL-39041. These all-terrain vehicles have very good cross-country ability and are indispensable for off-road operation during mudslide or deep snow, but they often have transmission failures, especially the shafts on which the wheel reduction gear of both the front and rear axles are installed. In the transmission of these vehicles on the tires of ultra-low pressure, the units from a number of commercially produced vehicles were used. The use of such units reduces the cost of construction and simplifies the production technology, maintenance and repair, but also creates certain difficulties in the design of this type of ATV, in some cases, increases the weight and dimensions. The experimental data are compared with the data of other authors and with calculated data. The obtained data are compared with the experimental and calculated data on the loading of the transmission elements of the UAZ-31512 automobile, the main units of which are used in the layout diagram of the snow aerial vehicle. The results of the studies indicate that the main reason for the failure in the transmission of the snow thrower TREKOL-39041 is the operating conditions, including somewhat different from ordinary tires, the interaction of the ultra-low pressure tires with the best traction and coupling properties with the supporting surface, and a more complex transmission scheme, than for conventional all-terrain vehicles, in which the transmission is simply assembled from the units of a number of serially produced automobiles and calculations of the dynamic loading of its elements on the forced modes are not conducted, which leads to the appearance of significantly exceeding the permissible values of stresses in the splined joint of the wheel gear shaft, to its plastic deformation and failure.

The description of multifunctional test bench construction to determine the basic operational characteristics of transmissions of automobiles and trucks designed in Volgograd State Technical University is provided. The description of its mathematical model created on the basis of the spatial dynamic schema is given and the results of calculation of test bench mass and inertia parameters are provided. The models of moving masses are the masses of transmission rotating elements, which transmit torque, transmission housing, test bench frame, that consists of two subframes, two hubs, DinaPack loading device, including a hydraulic machine. The values of parts inertia moments and stiffness of its joints are obtained by DASP software package and SolidWorks 3D CAD system. On the first stage to carry out the simulation capabilities at various loading conditions and forecast their results without a long-term field tests, on the basis of the structural scheme of test bench the flat dynamic model was created, which besides the data on composition and communication of the masses, contains data on elastic, inertial and dissipative parameters of its elements. On the next stage the spatial structural test bench scheme was created, on the basis of which in “Universal mechanism” program the spatial dynamic model was made. The dynamic model of test bench includes 31 inertial masses influenced by linear, contact, bipolar and special forces. To check the adequacy of the created model at the initial stage the calculation of fundamental frequencies of its masses in the range from 0 to 10000 Hz was made. The comparison of its values with the results of processing of experimental digital oscillograms of test bench masses oscillations showed sufficient for the solution of engineering problems convergence of results.

This paper describes the technology of creating the model of drivetrain of the tracked agricultural tractor Chetra 6C-315. Two-dimensional dynamic models do not provide an accurate representation of the whole complex of active and reactive forces acting on moving masses. Three-dimensional models provide much more opportunities for describing loading processes. The model was created in the program package “Universal mechanism” on the base of the kinematic scheme of transmission of tractor CHETRA 6C-315. The model consists of three main types of elements: “rotational joint”, “gearing”, and “planetary gear”. A program package includes a mathematical description of each element and the user has to specify only elements properties. In a planetary gear model for defining sun gear, crown gear, and carrier, joint with six degrees of freedom was used, and the connection between satellite and carrier is described with the rotational joint. As the result of full description describing of all elements of the tractor transmission, its three-dimensional model was obtained. The model takes into account reactive forces and moments from the casing and frame elements, and also from the engine. The model allows specifying a character of engine torque changing during the research. The characteristic of the engine torque is obtained from an indicator diagram beforehand. The analysis of results allows to find transmission areas with the highest dynamic load and to propose design ways for decreasing this load.

During a 10-day URSI World Day observational campaign beginning on August 1, 2011, an isolated, major geomagnetic storm occurred. On August 5, Kp reached values of 8− and Dst dropped to −113 nT. The occurrence of this isolated storm in the middle of a 10-day URSI World Day campaign provides and unprecedented opportunity to observe the coupling of solar wind energy into the magnetosphere and to evaluate the varied effects that occur in the coupled magnetosphere–ionosphere–thermosphere system. Dramatic changes in the ionosphere are seen at every one of the active radar stations, extending from Greenland down to equatorial Peru in the American sector and at middle latitudes in Ukraine. Data from TIMED and THEMIS are shown to support initial interpretations of the observations, where we focus on processes in the middle latitude afternoon sector during main phase, and the formation of a dense equatorial ionosphere during storm recovery. The combined measurements strongly suggest that the changes in ionospheric conditions observed after the main storm phase can be attributed in large part to changes in the stormtime thermosphere. This is through the generation of disturbance dynamo winds and also global neutral composition changes that either reduce or enhance plasma densities in a manner that depends mainly upon latitude. Unlike larger storms with possibly more sustained forcing, this storm exhibits minimal effects of persistent meridional stormtime wind drag, and little penetration of solar wind electric potentials to low latitudes. It is, therefore, an outstanding example of an impulsive event that exhibits longer-term effects through modification of the background atmosphere.

Analysis of operational failures in drivetrain details of vehicles equipped with extra-low pressure tires has been performed. Imperfection of existing method for simplified calculation of those drivetrains is shown.

The paper describes approximation method to the operational conditions of loading tractor transmission on the test bench when reproduction of dynamic loading modes.

The paper provides information about design of made in Volgograd State Technical University multi-functional test bench for determination of the basic operational characteristics of automobiles and automotive trucks transmissions. The test bench allows evaluating the level of vibration load of transmission elements in a wide range of operating modes. It also allows investigating modes of propagation of torsional vibrations on the shaft lines, determining overall efficiency of the transmission, noise intensity and vibration of units. The test bench allows receiving characteristics of the fields of thermal loading, investigating influence of lubrication system parameters on changing operational parame- ters. It also allows conduct life cycle testing of transmissions or their components.

УДК 550.385.4, 550.358:550.388 Приведены результаты расчетов эффектов возмущений теплового и динамического режимов верхней атмосферы Земли во время сильной магнитной бури 13–14 ноября 2012 г. Магнитная буря вызвала целый комплекс процессов, сопутствовавших возмущениям плазмы, электрических и магнитных полей в различных областях околоземного пространства. Подтверждено наличие в геомагнитных бурях как индивидуальных особенностей, так и общих закономерностей. Ключевые слова: геокосмическая буря, ионосферное возмущение, некогерентное рассеяние, динамические и тепловые процессы Статья поступила в редакцию 01.10.2014 Radio phys. radio astron. 2014, 19(4): 336-347 СПИСОК ЛИТЕРАТУРЫ 1. Домнин И. Ф., Емельянов Л. Я., Кацко С. В., Черногор Л. Ф. Ионосферные эффекты геокосмической бури 13–14 ноября 2012 г. // Радиофизика и радиоастрономия. – 2014. – Т. 19, № 2. – С. 170–180. 2. Черногор Л. Ф., Домнин И. Ф. Физика геокосмических бурь. – Харьков: ХНУ имени В. Н. Каразина, 2014. – 408 с. 3. Черногор Л. Ф. Физика Земли, атмосферы и геокосмоса в свете системной парадигмы // Радиофизика и радиоастрономия. – 2003. – Т. 8, № 1. – С. 59–106. 4. Григоренко Е. И., Пазюра С. А., Таран В. И., Черногор Л. Ф., Черняев С.В. Динамические процессы в ионосфере во время сильнейшей магнитной бури 30–31 мая 2003 г. // Геомагнетизм и аэрономия. – 2005. – Т. 45, № 6. – С. 803–823. 5. Salah J. E. and Evans J. V. Measurements of thermospheric temperature by incoherent scatter radar. In: Space Research XIII. – Berlin: Academie – Verlag, 1973. – P. 268–286. 6. Picone J. M., Hedin A. E., Drob D. P., and Aikin A. C. NRLMSISE-00 empirical model of the atmosphere: Statistical comparisons and scientific issues // J. Geophys. Res. Space Phys. – 2002. – Vol. 107, Is. A12. – P. SIA15-1–SIA15-16. 7. Бэнкс П. М. Тепловая структура ионосферы // ТИИЭР. – 1969. – Т. 57, № 3. – С. 6–30. 8. Schunk R. W. and Nagy A. F. Ionospheres: Physics, Plasma Physics, and Chemistry. – Cambridge, UK: Cambridge University Press, 2004. – 554 p. 9. Banks P. M. Charged particle temperatures and electron thermal conductivity in the upper atmosphere // Ann. Geophys. – 1966. – Vol. 22. – P. 577–584. 10. Dalgarno A. and Degges T. C. Electron cooling in the upper atmosphere // Planet. Space Sci. – 1968. – Vol. 16, Is. 1. – P. 125–127. 11. Сергеенко Н. П. Оценки электрических полей во время ионосферных возмущений. В кн.: Ионосферное прогнозирование. – М.: Наука, 1982. – С. 91–96. 12. Брюнелли Б. Е., Намгаладзе А. А. Физика ионосферы. – М.: Наука, 1987. – 528 с. 13. Домнин И. Ф., Емельянов Л. Я., Ляшенко М. В., Харитонова С. В., Черногор Л. Ф. Ионосферные процессы, сопровождавшие геокосмическую бурю 5–6 августа 2011 г. // Радиофизика и радиоастрономия. – 2012. – Т. 17, № 4. – С. 320–332. 14. Григоренко Е. И., Лысенко В. Н., Таран В. И., Черногор Л. Ф. Результаты радиофизических исследований процессов в ионосфере, сопровождавших сильнейшую геомагнитную бурю 25 сентября 1998 г. // Успехи современной радиоэлектроники. – 2003. – № 9. – С. 57–94. 15. Григоренко Е. И., Лазоренко С. В., Таран В. И., Черногор Л. Ф. Волновые возмущения в ионосфере, сопровождающие вспышку на Солнце и сильнейшую магнитную бурю 25 сентября 1998 г. // Геомагнетизм и аэрономия. – 2003. – Т. 43, № 6. – С. 770–787. 16. Кацко С. В., Домнин И. Ф., Емельянов Л. Я., Ляшенко М. В., Черногор Л. Ф. Ионосферная буря 5–6 августа 2011 г.: результаты расчетов основных эффектов // Радиофизика и радиоастрономия. – 2014. – Т. 19, № 1. – С. 26–39. 17. Данилов А. Д. Реакция области F на геомагнитные возмущения (обзор) // Гелиогеофизические исследования. – 2013. – № 5. – С. 1–33. 18. Пазюра С. А., Таран В. И., Черногор Л. Ф. Особенности ионосферной бури 4–6 апреля 2006 г. // Космічна наука і технологія. – 2008. – Т. 14, № 1. – С. 65–76. 19. Mansilla G. A. Mid-latitude effects of a great geomagnetic storm // J. Atmos. Sol.-Terr. Phys. – 2004. – Vol. 66, No. 12. – P. 1085–1091. 20. Mansilla G. A. Some effects in the upper atmosphere during geomagnetic storms // Adv. Space Res. – 2010. – Vol. 47, No. 6. – P. 930–937. 21. Sojka J. J., David M., Schunk R. W., and Heelis R. A. A modeling study of the longitudinal dependence of storm time midlatitude dayside total electron content enhancements // J. Geophys. Res. Space. Phys. – 2012. – Vol. 117, Is. A2. – id. A017000.

Results of prospects investigation of dynamic oscillations absorbers using in suspensions of tractor cabs are described. Design of dynamic absorber is developed and patented. On the basis of calculation and experimental research, it is shown that in practice under all modes of moving of tractor unit, the cab springing system with dynamic absorbers ensures the best protection of operator position against vibration in comparison to systems with serial rubber vibration isolators.

Calculation of dynamic and thermal processes parameters during the severe magnetic storm of August 5–6, 2011 (Kp max=8−) are presented. The magnetic storm was accompanied by negative ionospheric disturbance over Kharkiv which caused a number of changes in ionosphere. Plasma heating was observed during electron concentration depression in the F-layer which was accompanied by changes in neutral atmosphere composition and ionospheric dynamics.

The observation results of the effects in the geospace plasma during a partially (magnitude ∼0.42) solar eclipse are presented. The experimental data were obtained with an incoherent scatter radar of the Institute of the Ionosphere (near Kharkov). During the eclipse, the density at the F2 layer maximum decreased by 32%, the foF2 critical frequency decreased by 17.5%, and the altitude of the F2 layer maximum increased insignificantly. At altitudes of 290–680 km, the electron density decreased by ∼25%. During the eclipse, the electron and ion temperature decreased by 70–180 and 0–140 K, respectively, at altitudes of 190–490 km. Near the eclipse main phase, the plasma velocity vertical component decreased by 10–45 m/s at altitudes of 200–470 km, respectively. At the time of the eclipse main phase, the hydrogen ion fractional density increased by 50% as compared to the reference day at altitudes of 450–650 km.

The observations of the effects of the partial (about 77%) solar eclipse (SE) of March 29, 2006, in the ionospheric plasma are presented. The experimental data were obtained using the Kharkov incoherent scatter radar. At the moment of the maximum phase of SE, a decrease in the critical frequency of the ionospheric F2 layer by 18%, a depletion of the density in the F2 layer maximum by 33%, and an increase in the maximum height zm by 30 km were observed. The solar eclipse caused a decrease in the electron and ion temperatures by 150–300 and 100–200 K, respectively, within the height range 210–490 km. An increase in the relative density of the hydrogen ions during the maximum phase of SE by 20–25% within the height range 900–1200 km is detected. Calculations of the parameters of dynamical processes and thermal regime of the ionospheric plasma during SE are performed.

The modeling results of the zonal electric field and the vertical component of the plasma transfer velocity due to electromagnetic drift during August 5–6, 2011 and November 13–15, 2012 magnetic storms were presented. Confirmed that has a penetration of electric fields from magnetospheric origin in the mid-latitude ionosphere during strong geomagnetic disturbances. For the considered disturbed periods the neutral wind parameters were calculated using Kharkiv incoherent scatter radar data.