This study focuses on the design and optimization of the geometric parameters of gears in electric vehicle (EV) transmissions to enhance performance, efficiency, and noise reduction. The optimization process was conducted using KISSsoft, considering constraints such as input speed and torque, transmission system volume, and gear ratios for each driving mode. A novel aspect of this research is the integration of transmission efficiency analysis with a variable efficiency coefficient into the optimization workflow, which has been demonstrated to significantly influence the optimal design of multi-speed EV transmissions. Throughout the optimization, key factors such as tooth bending stress, contact stress, contact ratio, and specific sliding were analyzed. Additionally, the impact of module variations on gear profile geometry, overlap ratio, tooth count, and gear pair mass was investigated. Strength calculations for the optimized gear pairs, determined for all geometric parameters using KISSsoft, were performed in accordance with the mathematical model outlined in ISO 6336, and the results were subsequently compared. The findings emphasize the critical role of profile modifications and precise gear design in optimizing gear performance, ultimately contributing to improved efficiency, reliability, and service life.

https://doi.org/10.48081/JAKQ6441

2025

Issue 2

This article explores modern approaches to the use of innovative reinforcement in the construction of reinforced concrete structures. The main focus is on composite and polymer materials, which possess unique properties such as increased corrosion resistance, reduced weight, and improved mechanical performance. These characteristics open up wide opportunities for the application of such materials in construction, especially in conditions of high humidity or aggressive environments. However, despite the obvious advantages, there are also significant obstacles to the widespread adoption of new types of reinforcement. These include insufficient development of regulatory documents, high material costs, and their limited availability on the market. The article also analyzes the economic aspects of using innovative solutions, including their impact on the overall cost of construction and project timelines. Particular attention is paid to the prospects for the development of reinforcement technologies aimed at improving the durability, reliability, and efficiency of reinforced concrete structures. The possibilities of optimizing construction processes through the introduction of new materials and technologies, as well as the need for their adaptation to modern industry requirements, are considered. An important aspect of the work is the emphasis on interdisciplinary research, which can become the key to developing comprehensive solutions to overcome existing barriers. Thus, the article not only highlights the advantages of next-generation reinforcement but also offers practical recommendations for its broader application in construction practice.

https://doi.org/10.48081/JEWB8462

2025

Issue 2

Тo enhance the reliability of technologies used in additive manufacturing and expand their capabilities, the integration of the printing system with traditional technologies is being considered. However, one of the main challenges in this process is the inaccurate positioning of the print head, which can lead to a decrease in the quality of the fabricated structure. To address this issue, this paper proposes the use of a manipulator that compensates for deviations of the boom of traditional machinery used as a manipulator during 3D printing, thereby ensuring precise positioning of the print head. In selecting the manipulator, an analysis of serial and parallel manipulators was conducted. The manipulator effectively compensates for deviations along the XYZ axes in the working space, improving printing accuracy and quality. To accomplish this task, the Clavel delta robot was chosen due to its high speed, precise positioning capabilities, and sufficient rigidity provided by its parallel kinematics. During the study, direct and inverse kinematics problems were solved, the working area of the manipulator was determined, and its suitability for the given task was confirmed. The obtained results can be used to further optimize the 3D printing process and enhance its technological efficiency.Keywords: concrete 3D printing, manipulator, inverse kinematics, forward kinematics, Clavel's delta robot.

https://doi.org/10.48081/ECWK2774

2025

Issue 2

This paper examines the development and optimization of the control system for a lower limb exoskeleton with a gravity-independent suspension. The main focus is on creating adaptive control algorithms aimed at improving user mobility, reducing energy consumption, and ensuring a high degree of device autonomy. The study includes an analysis of existing exoskeleton designs, identifies their limitations, and proposes new approaches to optimizing mechanical structures, software, and power management systems. The developed control model is based on the use of inertial sensors, electromyographic sensors, and machine learning algorithms, allowing the exoskeleton to adapt to changes in the external environment and individual user characteristics. Special attention is given to the integration of regenerative systems that convert kinetic energy from movement into electrical energy, thereby extending the device's autonomous operation time. Empirical tests confirmed the effectiveness of the proposed solutions, demonstrating a significant reduction in muscle load, increased stability, and overall efficiency of the exoskeleton in various operating conditions. The development of a lower limb exoskeleton with a gravity-independent suspension represents a significant advancement in robotics, rehabilitation medicine, and industrial applications, opening new prospects for intelligent assistive devices capable of adapting to a wide range of tasks and user needs.

https://doi.org/10.48081/HFDE5458

2025

Issue 2

This work introduces a new technique for improving the performance of copper wire by combining room temperature drawing to create a gradient microstructure with rotating equal-channel step matrix deformation. A surface layer with nanoscale grains (500 nm) up to 1 mm is created by this combination process, which also introduces twisting and stretching forces. At the middle of the wire, these nanoscale grains eventually change into bigger micrometer-sized grains (4µm). The deformation reduces the average grain size by aligning the grains, causing extensive twinning, and increasing the density of large-angle grain boundaries, according to electron backscatter diffraction research. These large-angle boundaries play a significant role in enhancing the mechanical properties of the wire. With 68% at the surface, 42% in the middle, and 25% in the center, the density of these large-angle boundaries is not uniform, suggesting a customized microstructure for better mechanical performance, including higher strength and improved ductility, which can be crucial for various industrial applications.

https://doi.org/10.48081/CIZG7551

2025

Issue 2

Centrifugal pumps used in transport engineering are of interest from the point of view of improving their quality of operation, efficiency and operational reliability. A number of scientific studies are devoted to the problems of dynamic processes occurring during pump operation; development of computer models for studying dynamic stresses and vibrations of the main pump parts – the housing and the double-suction impeller. The rotor is a shaft on which the main part of the pump is installed-the impeller. The bearings are bearing units mounted on both sides of the wheel, in general, the system is represented as a rotor-dynamic system. Canitation processes that occur during pump operation contribute to the appearance of fluid pressure fluctuations and create vibrations of the system as a whole. The results of studying the dynamic characteristics of a centrifugal pump using the oscillation theory and frequency domain analysis, as well as the numerical simulation method, are presented. The results showed that vibration processes in the rotor depend of the geometry of the bearing supports, rotor balancing, and pump performance.

https://doi.org/10.48081/QCPX1418

2025

Issue 2

In this paper, we study the possibility of using calcium-containing ferroalloy ferroalumosilicocalcium (FASC) as a reducing agent in the production of refined ferrochrome. A comparative analysis of the standard technology using silicochrome and the developed method using FASC is carried out. Thermodynamic modeling in the temperature range from 300 to 3000 K using the TERRA software package was performed to determine the optimal process parameters. Experimental melts were carried out in a high-temperature resistance furnace "Tammana". The results of the studies showed that the use of FASC leads to a significant change in the phase composition of the slag: the content of calcium aluminates increases more than threefold, which helps to reduce the viscosity of the slag, improve its fluidity and reduce the melting point. The optimal range of slag basicity is 1.2–1.5, which ensures maximum extraction of chromium into the metal. The resulting alloy meets the requirements for refined grades of ferrochrome in terms of chemical composition, and the chromium content exceeds 65%. Thus, the use of complex ferroalloy FASK as a reducing agent allows increasing the efficiency of the process of obtaining refined ferrochrome, reducing chromium losses with slag and improving the metallurgical properties of slags.

https://doi.org/10.48081/SCIX5781

2025

Issue 2

Based on the analysis of the methods of crushing materials, the difficulties of crushing and existing grinders, the expediency of using the impact destruction method for fine and ultrafine grinding, as well as high-speed impact grinders, is substantiated. A mechanical and mathematical model of the impact destruction of material particles modeled by the shape of the beam has been developed, which makes it possible to predict the result of the grinding process and determine the rational parameters of the grinders. An engineering method in the form of simple functional relations for the theoretical calculation of stresses, the particle volume destroyed by a single impact of the working body, the grinding limit, the number of impacts of the working body and the time required to grind the particle from the initial to the final size, and the regulation of the parameters of the grinding process is proposed. The design of an impact grinder with an original organization of multi-stage grinding and increased energy stress of the process is proposed. The results of experimental studies of the multi-stage impact grinder, complementing the calculation method and proving the operability, efficiency and the possibility of practical use of the grinder, are presented. The proposed original multi-stage grinding scheme and the design of the grinder have opportunities for their further development and improvement. The results of the work can serve as a basis for further research on the processes of fine and ultrafine grinding of materials by impact, and the search for economical grinding possibilities.

https://doi.org10.48081/VEJS9382

2025

Issue 2

Ferroalloy production is one of the most significant areas of the metallurgical industry, but it is accompanied by significant emissions of dust particles containing toxic metals. These emissions not only worsen air quality, but also have a negative impact on soil, water bodies and human health. The article examines the main sources of pollution, including melting furnaces, gas purification plants, crushing and sorting processes, as well as waste accumulation. Special attention is paid to the characteristics of dust emissions, their size distribution and potential impact on the environment. An analysis of current research shows that PM10 and PM2.5 particulate matter pose the greatest danger, as they can enter the respiratory tract, causing chronic lung diseases, as well as cardiovascular and neurological disorders. Modern pollution minimization methods such as filtration systems, electrostatic precipitators, wet scrubbers and waste recycling are presented. The prospects for the introduction of new technologies, including automated monitoring of emissions and the use of alternative environmentally sound solutions, are being considered. The results obtained confirm the need for an integrated approach to reducing dust particle emissions at ferroalloy plants in order to minimize their impact on the environment and human health.

https://doi.org/10.48081/NVEL1782

2025

Issue 2

The costs that keep vehicles running contribute to the efficiency of transportation logistics. The variation of these costs over time, especially the exponential growth with increasing vehicle mileage, is an important issue in transport services and transportation. In this article the change of expenses on maintenance of work of motor transport at its operation in transport logistics is investigated. Costs ensuring serviceability vary significantly depending on the distance travelled by the vehicle, technical condition, mode of operation and other factors. The study analysed the size and dynamics of the costs required to ensure the operation of the vehicle. Information was provided on the changes in the wear curve, in particular, the level of wear of various components of the car in repair work, such as the engine, wheels, steering and braking systems. The study showed that the cost associated with maintaining the serviceability of a vehicle increases exponentially proportional to the distance travelled. This paper also proposed mathematical models describing the factors affecting vehicle operability and their interrelationships. The obtained data allow predicting and planning repair costs in advance in order to ensure efficient operation of vehicles.

https://doi.org/10.48081/KJYW1697

2025

Issue 2