Факультет робототехніки та штучного інтелекту
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Item type:Наукова стаття, Creation of automatic clamping mechanisms for spindle assemblies of machine tools using a formalized description of structural elements(2022) Prydalnyi, BorysThe characteristics of the functioning of automatic mechanisms for clamping workpieces and cylindrical tools in the spindle assemblies of metalworking machines determine the potential for improving the productivity and quality of processing. The conducted research is aimed at developing new approaches to the creation of automatic clamping mechanisms with qualitatively new and necessary characteristics of their functioning. The formation of new characteristics is achieved by implementing appropriate changes at the structural level of an object.Item type:Наукова стаття, Identification of Analytical Dependencies of the Operational Characteristics of the Workpiece Clamping Mechanisms with the Rotary Movement of the Input Link(2021) Prydalnyi, Borys; Sulym, HeorhiyThe research is devoted to the problem of determining the efficiency of the workpiece fixing mechanism operation. Improving characteristics of workpiece fixing is one of the required conditions to increase the cutting modes, which may help to enhance the machining productivity. The study investigates the main characteristics and general features of a new structure of clamping mechanisms with electromechanical actuators for fixation of rotation bodies. The main advantages of using electromechanical clamping actuators with self-braking gear are presented. Two simplified dynamical models for the description of different stages of the clamping process are developed. The calculation scheme was formulated to find out how the mass-geometric parameters of mechanism elements should influence the main characteristics of the clamping mechanisms of this type.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, Comparison of the effectiveness of time series analysis methods: SMA, WMA, EMA, EWMA, and Kalman Filter for Data Analysis(Lublin: Lublin University of Technology, 2023) Gumeniuk, Larysa; Humeniuk, PavloIn time series analysis, signal processing, and financial analysis, simple moving average (SMA), weighted moving average (WMA), exponential moving average (EMA), exponential weighted moving average (EWMA), and Kalman filter are widely used methods. Each method has its own strengths and weaknesses, and the choice of method depends on the specific application and data characteristics. It is important for researchers and practitioners to understand the properties and limitations of these methods in order to make informed decisions when analyzing time series data. This study investigates the effectiveness of time series analysis methods using data modeled with a known exponential function with overlaid random noise. This approach allows for control of the underlying trend in the data while introducing the variability characteristic of real-world data. The relationships were written using scripts for the construction of dependencies, and graphical interpretation of the results is provided.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.