Факультет робототехніки та штучного інтелекту
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Item type:Наукова стаття, RESEARCH ON OVERSIZED LOAD PACKAGING(2024-05-24) Valetskyi, Bohdan; Tolstushko, Mykola; Tolstushko, Nataliya; Fedorus, YuriiModern packaging is rapidly developing in all industries. The development of packaging in agriculture, processing, and construction industries is intensive due to a significant share of large-sized cargo (styrofoam plates, rolls of mineral wool, fuel briquettes from agricultural and forest biomass, etc.). Therefore, the urgent task is to create equipment for high-quality packaging of large cargoes. During the large-size packaging process, the stretched film is welded. One of the problems is the need to tighten the package with a film, to ensure the density and strength of the welds, which will withstand the stretching of the film after sealing the formed package. The design of such machines is specific because it includes both the mechanisms of forming the package and the mechanisms of wrapping it with a film followed by welding. The necessity of shrinking large-sized packages during their welding, the use of new, including multi-layer polymer combined materials, requires a reduction in energy consumption, improvement of existing packaging methods and machines that implement them, and replacement of heat shrinking with mechanical shrinking. A new roller mechanism for welding and cooling the film is described. An experimental setup has been developed for researching the process of packing large cargoes. The dependence of the quality of the welding seam of the packaging film on the temperature and force of its welding, as well as the duration of heating and cooling of the seam, was determined experimentally. Basis on the analysis of the results of the experiments, the substantiation of the tightening parameters of large packages was carried out, which makes it possible to calculate the main parameters of the tightening mechanism, the optimal choice of the film wrapping material, and the reliable shaping of the package itself.Item type:Наукова стаття, Thermoforce Deformation of Nonthin Anisotropic Cylindrical Shells Protected by a Functionally Graded Material(Springer Science and Business Media LLC, 2026-05) Trach, Volodymyr; Podvornyi, Andrew; Bondarskyi, OleksandrBy using the modified Hu–Washizu variational principle, we obtain an inhomogeneous three-dimensional system of equilibrium differential equations. The application of this system makes it possible to study the stress-strain state of a composite cylindrical anisotropic shell for the force and temperatures impacts specified on its end faces. The anisotropy of the material of the shell is characterized by a single plane of elastic symmetry in each layer. By the Bubnov–Galerkin method, the original threedimensional system of equilibrium equations is reduced to a one-dimensional system of first-order ordinary differential equations with respect to the radial coordinate. The obtained boundary-value problem is solved by the numerical method of discrete orthogonalization. We present the results of numerical analysis of the stress-strain state of an anisotropic cylindrical composite boron–plastic shell protected against the action of high-intensity temperature fields by a layer of a nanoceramic functionally graded material.Item type:Наукова стаття, Powder Modifier Effect on the Mechanical Behavior of Polyurethane Foams(2026) Mikulich, Olena; Furs, Tetiana; Shemet, Vasylyna; Bondarskii, OlexandrThe paper investigated the influence of a powder modifier in the form of finely dispersed perlite on the mechanical behavior of rigid polyurethane foams under static monotonic and multi-cycle loading, which causes the material’s plastic deformation. The studies were conducted for polyurethane foam samples with different weight contents of perlite powder, ranging from 0 to 10 mass parts. Infrared spectroscopy established heterogeneous inclusion of the perlite additive as a mineral filler into the polymer matrix without changing the main structural bonds of modified polyurethane foam (MPU). The change in the values of Young’s modulus, yield strength and relative plastic deformation depending on the quantitative content of the powder modifier was investigated. It was established that the addition of a powder modifier, perlite, contributes to an increase in the stiffness of MPU foam. The change in Young’s modulus under multi-cycle loading within each series of experimental samples was evaluated. The results confirm the effectiveness of perlite powder for modifying polyurethane foam not only for solar radiation protection, but also to increase the stability of the mechanical characteristics of rigid polyurethane foams.Item type:Наукова стаття, Synthesis of Bandpass Filter as a Four-Pole Based on a Non-Homogeneous Line(2024-07-29) Kozlovskiy, Valeriy; Kozlovskiy, Valerii; Boiko, Juliy; Balanyuk, Yuriy; Yakymchuk, NataliaThe article deals with the synthesis of band-pass filters (BPF) for the design of microwave filtering devices, by using non-homogeneous lines (NL) with the selection of the appropriate wave impedance W. For this purpose, equivalent NL substitution circuits were created in the region of resonant and anti-resonant frequencies, and four-pole matrices of the transmission line were determined, whose matrix of impedances and admittances does not have partial poles, and the transmission admittance and transmission impedance do not have zeros. BPF prototypes were synthesized with two parallel plumes based on a closed homogeneous line and one plume based on three NLs. A band-pass filter with an extended blocking band was implemented, and its amplitude-frequency characteristics were obtained. The use of NLs as resonators allows the choice of wave impedance to increase the blocking band of the BPF compared to the BPF on resonators based on homogeneous lines.Item type:Наукова стаття, Mathematical Modeling of a Small-Dimension Hydropulse Vibrator with a Valve-Driven Pressure Pulse Generator(2026-04-01) Povstyanoy, Oleksandr; Obertyukh, Roman; Slabkyi, AndryiThe article presents research on a new compact vibrator design based on a hydraulic pulse drive with a built-in valve-type pressure pulse generator. Based on scientific assumptions, an approximate cycle diagram of the working cycle, a structural diagram of the vibrator, and a representation of the hydraulic link of its hydraulic system as a Kelvin–Voigt model were developed. A dynamic model of the vibrator was designed, in which the hydraulic link interacts with the moving links via transmission ratios. Based on simplified dynamic models of the forward and reverse strokes of the executive element, a mathematical model of the vibrator was developed using the d’Alembert principle, resulting in a system of 2nd-order differential equations describing the motion of the executive element’s mass during its forward and reverse strokes. Consumption for energy equations at time intervals was also considered according to the approximate cycle diagram of the vibrator’s working cycle and the conditions of uniqueness that limit the movement of the mass of the executive element and the deformation of the hydraulic link. To provide a detailed analysis of the developed mathematical model, Python program code was written. The workflow was visualized in Google Colab. It was confirmed that the operating frequency range of a hydraulic pulse vibrator of this design is not a single fixed number – it is parametric and depends on the settings of the hydraulic system. By adjusting the pumping station parameters and the stiffness of the vibrator’s elastic elements, it is possible to achieve an actuator frequency up to 150 Hz and an amplitude of up to 2 mm.Item type:Наукова стаття, An impact of technological factors on the kinematic accuracy of cylindrical gear wheels during machining(Sumy State University (ROR), 2025-03-03) Povstyanoy, Oleksandr; Halchuk, Tetyana; Bembenek, Mihal; Valetskyi, BohdanThe work analyzes the means of controlling the accuracy of gears from the point of view of ensuring the manufacture of parts of a given quality. A theoretical study of the influence of the geometry and accuracy of the elements of the technological system and the process of gear milling with a worm cutter on the kinematic accuracy of cylindrical gears has been carried out. A method of conducting experimental studies of the wheel on the kinematic accuracy has been selected, which consists in comparing the circular distances between the same profiles of two teeth of the wheel with similar distances between the profiles of the other two teeth of the same wheel. The influence of the technological modes of processing of the gear milling process on its accuracy indicators has been experimentally studied. An optimization model for selecting technological modes of processing has been developed in order to ensure the required kinematic accuracy of the gear after the gear milling operation with a worm cutter due to the error of the accumulated step, as well as to reduce the number of experiments. The work was carried out using data from a private complex study of the elementary indicator of kinematic accuracy of the accumulated error of the wheel pitch, obtained during measurement control. During the work, metrological means and methods of gear wheel control were used. The research results were processed by methods of mathematical statistics.Item type:Наукова стаття, Evaluation of the surface characteristics of VT8 titanium alloy bio-functionalized through plasma electrolytic oxidation(2024-03-15) Povstyanoy, Oleksandr; Imbirovych, Nataliia; Zvirko, OlhaTitanium and its alloys are considered promising materials in the medical field due to a number of mechanical and corrosion properties, as well as biocompatibility. In order to improve the operational properties of such alloys, their surface is modified by various methods, particularly plasma-electrolytic oxidation (PEO). The main feature of the PEO method is the wide possibility of controlling the physical and mechanical properties of coatings by changing the electrolyte composition and operating modes. These include hardness as one of the important functional properties of oxide-ceramic biocompatible coatings which can be changed in a wide range. The hardness should be controlled to avoid brittle fracture of coatings. In this work, a number of PEO regimes were developed by varying the electrolyte composition, the ratio of anodic to cathodic currents, and the treatment duration. Coatings with a hardness in the range of 1400–2500 MPa and a thickness of 3.4–12 μm were synthesized. An acceptable correlation between the hardness and thickness of the coating was revealed. It enables the assessment of coating thickness by measurements of hardness and can be used for non-destructive evaluation of coating thickness.Item type:Наукова стаття, Automatic device with self-braking for fixation objects in executive links of technological equipment(2025) Prydalnyi, BorysThe main characteristics of a new automatic device for the fixation of objects in executive links of technological equipment, which determine its suitability for use, are considered. The device is based on a new structure that ensures its self-braking after the process of object fixation and increases the reliability of holding the objects, which is especially important in safety-critical applications. The proposed structure can be implemented for use in various types of executive links of technological equipment, and in the paper, it is considered the most complex application of the device—as part of a spindle assembly. For the proposed design, the method of calculating the main parameters of this type of mechanism is presented. Based on the results of the research, analytical and graphical dependencies have been obtained describing the change of the clamping force from 45 to 15 kN when increasing the spindle speed up to 10000 rpm, and the dependence of the clamping force on the torque at the input link. Based on the results of the research, a preliminary conclusion has also been drawn regarding the possibility of using electromechanical clamping mechanisms of the proposed type as a part of spindle units of machine tools, also because the rotor diameter of the mechanism is within 100 mm and the stator is within 200 mm.Item type:Наукова стаття, Study of sapropel processing process in rotary disperser-mixer(Jelgava, 2025-05-21) Tsiz, Igor; Khomych, Serhiі; Tsyz, Tetiana; Holii, ValentynOrganic sapropel is a high-quality source of soil humus replenishment and is highly effective when applied to degraded and technogenically contaminated soils. The specific conditions of sapropel deposit formation result in a dispersed structure containing 92-98% water. To utilize sapropel as a solid organic fertilizer, its moisture content must be reduced to 60%, which requires significant energy input. One approach to utilizing organic sapropel in its natural moisture state is treating it with a weak alkaline (or acidic) solution to produce humic fertilizers. To ensure a high-quality reaction between sapropel and alkaline solution, a laboratory-scale rotary disperser-mixer was developed. This design facilitates micro-mixing of naturally moist sapropel with an alkaline solution in an annular channel formed between the rotor and stator. The aim of this study is to determine how the parameters of sapropel treatment in the developed disperser-mixer influence the activation of the humic complex. The study investigated the effects of the alkali solution concentration, the sapropel-to-alkali solution ratio, and the disperser-mixer rotor speed on the treatment process. To assess the effectiveness of the treated sapropel, a laboratory experiment was conducted, growing oil radish with varying fertilizer applications. A four-factor Box-Behnken experimental design was used to develop a mathematical model describing the effect of the treated sapropel on oil radish growth. The results indicate that sapropel processed using the developed rotary disperser mixer, compared to untreated sapropel, led to a 5-20% increase in oil radish plant height.Item type:Наукова стаття, Modeling dynamic and static operating modes of a low-power asynchronous electric drive(2025-06-27) Lyshuk, Viktor; Moroz, Sergiy; Selepyna, Yosyp; Zablotskyi, Valentyn; Yevsiuk, Mykola; Satsyk, Viktor; Tkachuk, AnatoliiThe article presents a mathematical model of the asynchronous motor in oblique coordinates, based on differential equations expressedin the standard Cauchy form. The differential equations of traditional models are implicitly formulated; therefore, during numerical implementationfor prolonged processes, matrix coefficient rotation leads to significant time expenditure and the accumulation of errors during integration. This complex task is proposed to be addressed by ensuring that the differential equations of the electromechanical state are non-stiff and, importantly, writtenin standard Cauchy form. The standard Cauchy form is essential for analyzing asynchronous motors, as changes in the number of unknowns significantlyrestructure the coefficient matrix. This formulation of the equations is convenient for numerical integration, as explicit methods, which are considerably simpler than implicit methods, can be implemented. To create a mathematical model, coordinate transformations were performed based on the classical theory of electric machines. The advantage of the proposed method of using different coordinate axes is the possibility of analyzing new variablesand obtaining constant coefficients in the equations of state of the electric motor.The model accounts for the electromagnetic interactions of the motor’s electrical circuits and their nonlinearity, enabling the simulation of electromagnetic and electromechanical processes. Transitional operating modes of the asynchronous motor have been modeled and analyzed. The proposed model can be utilized for analyzing the operation of motors both as standalone elements and as components of an electromechanical system. It is demonstrated that this model aligns with classical electrical machine theory.Simulation results are provided, along with their analysis.