Кафедра прикладної механіки та мехатроніки
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Item type:Наукова стаття, Information and measurement system for analyzing images of fundus tissue using computer-integrated technologies(2025-10-22) Povstyanoy, Oleksandr; Vynokurova, Olena; Denysiuk, Viktor; Lapchenko, Yuryi; Hrudetskij, RomanThe paper presents the results of research and development of a modern information and measurement system (IMS) designed for automated analysis of fundus images for the purpose of diagnosing and monitoring ophthalmic pathologies. The proposed system combines methods of digital medical image processing, artificial intelligence and computer vision, which allows ensuring high accuracy and objectivity of the diagnostic process. Particular attention is paid to the use of deep learning algorithms for the segmentation of anatomical structures of the retina and analysis of fluorescent images. A comprehensive method of photodynamic diagnostics and therapy has been developed, which is implemented based on a modified slit lamp with a laser illuminator. Effective methods of image registration and processing have been proposed, in particular their synchronization and spectral analysis, which allows for quantitative assessment of the state of tissues. The results of the study can be used in ophthalmological practice to increase the accuracy of early detection of pathologies, as well as in telemedicine and personalized medicine systems.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, Formation of Coatings on Titanium Alloys Saturated with Biocomponents by the PEO Method(Cham: Springer, 2025-02-14) Povstyanoy, Oleksandr; Imbirovych, Nataliia; Boiarska, Inna; Nykoliuk, TamaraIn the work, the influence of the composition of the electrolyte on the elec-trophysical parameters of the synthesis of coatings with increased biocom-patible properties was studied. It was established that under conditions of increased electrolyte concentration, the voltage at which the coating is syn-thesized decreases. This effect can be explained by the thermodynamic Gibbs conditions. According to these conditions, the system needs more energy when the medium contains more elements, which must also con-sume a certain amount of energy. The authors found that sodium salts in-crease the conductivity of the working environment. This effect affects the speed of the synthesis process and can reduce the cost of the energy re-serve of the system as a whole. Spectral analysis established that during the synthesis of a titanium alloy in an alkaline electrolyte, an equilibrium non-degenerate quasi-ideal plasma is realized in the discharge channel with a temperature of (1...1,1)×104 K and an electron density of (3,2...3,4)×1022 m-3. It is under these conditions that molecules dissociate into ions and interact with the components of the elec-trolyte, which leads to oxidation of the surface of valve metals and the formation of stable compounds with high biocompatible properties.Item type:Наукова стаття, Production and Surface Research of a New Material with the Addition of Diatomite for Potential Filtration Applications(Cham: Springer, 2025-07-12) Povstyanoy, Oleksandr; Imbirovych, Nataliia; Smetjukh, Bohdan; Karbovska, YuliiaThis work is dedicated to the research and study of the possibility of using Natural minerals such as Diatomaceous Earth (diatoms) for filtering various environments. The extraordinary progress and prospects of diatomaceous earth (DE) as a biomatrix material for creating porous materials are relevant and interesting. The unique structures of DE, including its mesoporosity and large surface area, have made it a key material for the filtration process. Its biotemplating ability can initiate the creation of highly efficient porous permeable materials. Its sufficient natural abundance and ecological properties are consistent with the increasing emphasis on sustainability in environmental solutions. Its complex structures and biotemplating capabilities will pave a compelling path in the future for the advancement of sustainable, highly efficient solutions for filtering environments, marking a significant step towards a more ecological and efficient future for humanity. This research paper explores the potential of DE as a bio-matrix material for creating a permeable material without delving into the complex filtration processes. Previous studies have shown that the use of Diatomaceous Earth with titanium powder in various proportions allows us to talk about the possibility of creating highly efficient porous permeable materials with branched porosity even for drinking water filtrationItem 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, THEORETICAL RESEARCH OF A NEW DESIGN OF A PARAMETRIC PRESSURE PULSE GENERATOR FOR A VIBRATORY HYDRAULIC DRIVE(2026-01-15) Povstyanoy, Oleksandr; OBERTYUKH, Roman; SLABKYI, Andrii; SUKHORUKOV, Sergey; KOTYK, SergeyBased on the results of the analysis of known circuit and structural designs of pressure pulse generators (PPG) in liquid, a new design of a single-stage parametric PPG with increased throughput capacity has been developed according to the connection diagram to the executive hydraulic cylinder of the hydraulic pulse drive (HPD) «at the inlet», the distribution links (first and second sealing stages) of which are combined with a high-rigidity slotted spring (SS). The newly designed PPG is used to control the HPD with a parametric-type actuating hydraulic cylinder. In order to create a scientifically sound methodology for the design calculation of the studied hydraulic impulse drive and PPG, a dynamic model of the HPD was developed, based on which and a sound structure of assumptions, a mathematical model of the HPD was constructed and analysed.Item type:Наукова стаття, Anti-friction Products from Composite Materials Based on Lh15 Steel Powder(2024-07-06) Povstyanoy, Oleksandr; Halchuk, Tetiana; Polinkevych, Romаn; Redko, OlhaThe work considers the possibility of manufacturing and using sintered composite products from a metal component in the form of alloy steel powder ob-tained from grinding waste of bearing production. The research was carried out at op-timal pressing parameters of 400...800 MPa, sintering at 1200°C for 2 hours from the moment of setting the specified temperature. The results of the first systematic studies of the strength and tribotechnical properties of sintered materials based on LH15 steel powder obtained from grinding slurries with copper and graphite additives are pre-sented. It was established that the tribotechnical characteristics of sintered products under conditions of medium loads mainly depend on the hardness of the composition. It has been experimentally verified that the high wear resistance and friction coefficient, which is on average 0.09, has a composition with a content of 2% graphite and 4% copper at a sliding speed of 5 m/s and a pressure of 10 MPa. It has been experimental-ly confirmed that the increase in the linear dependence of stress on deformation, in particular, when the strain is 8%, the stress is 1200...1400 MPa. This makes it possible to predict higher operational properties of products made from material of this com-position. The resulting anti-friction products have a significantly lower cost and a higher material utilization ratio compared to traditional materials.