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Зараз показуємо 1 - 7 з 7

Загальні відомості про журнал
(Харківський національний автомобільно-дорожній університет, 2025)
Modeling and investigation of deformation kinetics in polymer adhesive systems
(Харківський національний автомобільно-дорожній університет, 2025) Pustovoitova, O.; Пустовойтова, Оксана
The article studies the change in the elastic limit and tensile strength of acrylic adhesive over time - from the maximum value (short-term strength) to the minimum (long-term strength limit). The development of deformations in samples under constant loads ranging from 0.2 to 0.85 of the destructive ones was experimentally studied. It is shown that at stresses below the long-term strength limit, the deformation curve includes two sections: instantaneous deformations and viscous deformations that develop over time. Destruction occurs due to the accumulation of damage (cracks, defects), and its speed depends on the stress level and the configuration of the adhesive joint. Purpose. The aim of this study is to establish the patterns of change in the yield strength and ultimate strength of acrylic adhesive over time under sustained loading, as well as to analyze the damage accumulation process in adhesive joints depending on stress level. Methodology. The experimental research involved testing acrylic adhesive specimens under constant loads ranging from 20% to 85% of their short-term (ultimate) strength. The development of deformations over time was observed, and the nature of failure was recorded. Results. It was found that under stresses below the long-term strength limit, the deformation curve consists of two distinct regions: instantaneous (elastic) deformation and time-dependent (viscous) deformation. Failure occurs due to the progressive accumulation of micro-damage, including cracks and defects. The rate of degradation depends on both the stress level and the geometry of the adhesive joint. Originality. This work provides a comprehensive description, for the first time, of the transition from short-term to long-term strength of acrylic adhesive under constant loading, taking into account the influence of joint configuration on the failure rate. Practical value. The results can be applied to predict the durability of adhesive joints in structures operating under sustained loads, such as anchor systems, and to optimize joint geometry in order to improve reliability.
Problems of adaptation of foreign applicants to study in the educational program "Automotive Engineering"
(Харківський національний автомобільно-дорожній університет, 2015) Novina, N.; Новіна, Наталія Нарсенівна
The issue of student adaptation to studying at higher education institutions in Ukraine is extremely relevant, especially in the context of globalization, the active internationalization of the educational space, and the continuous increase in the number of international students choosing Ukraine for their higher education. Adaptation is a complex, multifactorial process that includes not only academic but also social, psychological, and cultural components, all of which are closely interrelated and mutually influential. Particular attention should be given to the effective integration of international students into the learning environment of Ukraine’s technical universities, where the educational process is characterized by a high level of intellectual demand, specialized terminology, and the need for advanced analytical skills. At the same time, it is noted that the academic community has paid insufficient attention to the impact of cultural distance on the adaptation process. The article emphasizes the importance of a thorough analysis of the adaptation process in the context of cultural differences, as the cultural distance between a student’s country of origin and the Ukrainian cultural environment can significantly influence the speed, effectiveness, and completeness of their integration into the academic and social setting of the university. Purpose. To determine the level of adaptation of international students enrolled in the "Automotive Engineering" program depending on cultural distance and to identify factors that facilitate or hinder this process. Methodology. The study involved 60 international students from Turkmenistan, Azerbaijan, Morocco, Tunisia, Cameroon, and Nigeria. The research methods included surveys (including the International Student Adaptation Scale), observations, interviews, and analysis of academic performance and extracurricular participation. The data were analyzed using both quantitative (mean, variance, correlations) and qualitative methods. Results. It was found that students from culturally closer regions (Group 1) were the most adapted, while those from countries with greater cultural distance (Group 3) experienced significant difficulties. The main barriers were language challenges, culture shock, differences in academic expectations, and psychological pressure. Practical value. The study developed recommendations to improve language training, cultural integration, and academic support, which can be implemented by higher education institutions to ensure more effective adaptation of international students and reduce academic attrition rates.
Variability in the interpretation of information in the investigation of road traffic incidents using 3D scanning devices
(Харківський національний автомобільно-дорожній університет, 2025) Leontiev, D.; Varlakhov, V.; Frolov, A.; Danets, S.; Don, Ye.; Леонтьєв, Дмитро Миколайович; Варлахов, Віталій Олександрович; Фролов, Андрій Анатолійович; Данець, Сергій Віталійович; Дон, Євген Юрійович
One of the key challenges in the investigation of road traffic accidents (RTAs) is the reliable determination of the collision mechanism between vehicles, especially in cases where the vehicles have been moved from the scene. Traditional methods of documentation and analysis often lack sufficient accuracy and objectivity. Goal. The aim of this study is to identify the mechanism of collision between two vehicles by analyzing and comparing their geometric damage patterns obtained via 3D scanning, followed by determining their actual relative positioning at the moment of initial contact. Methodology. To achieve this goal, a portable 3D scanner Artec Leo was used, enabling high-precision scanning of vehicles regardless of their location. The resulting 3D models of the damaged vehicles were aligned with each other and with a digital version of the accident scene diagram. During the analysis, vehicle orientation angles, the location of primary contact, movement directions, and damage characteristics were determined. Results. It was established that the collision occurred at an angle of 8–10° within the driving lane of vehicle 1. This conclusion is supported by the alignment of damage areas, the position of the front right headlamp of vehicle 1, and the distribution of glass and plastic fragments. The zone of initial contact was localized within 2 meters from the right edge of the carriageway. Originality. An integrated approach to digital traffic accident reconstruction using 3D scanning is proposed, allowing for accurate analysis even without access to the original accident scene. Practical value. The methodology can be applied in forensic vehicle examination, court investigations, and insurance case assessments to objectively determine the circumstances of a traffic collision.
Formulation of the problem of topology optimization of automobile and agricultural machinery structures
(Харківський національний автомобільно-дорожній університет, 2025) Tovt, B.; Leontiev, D.; Malyi, V.; Товт, Богдан Миколайович; Леонтьєв, Дмитро Миколайович; Малий, Віктор Миколайович
The demand for lightweight, durable, and efficient automobile and agricultural machinery structures requires advanced design methods. Topology optimization offers a solution by optimizing material distribution, but its application to complex structures is challenging due to varying loads and constraints. This study focuses on formulating the topology optimization problem to enhance structural efficiency and performance. Purpose. The primary goal of this paper is to contribute to the advancement of the scientific foundation of topology structural optimization, with a particular focus on tackling the complex optimization challenges encountered in automobile and agricultural machinery design. Methodology. Mathematical programming and modeling play a crucial role as foundational tools in the formulation of topology structural optimization problems within the automobile and agri-cultural machinery industry. Together, these tools facilitate the development of optimized structural designs that are not only lightweight and cost-effective but also capable of withstanding the demanding operational environments of agricultural equipment and automobiles. Results. This paper provides a short review and analysis of the current state of topology structural optimization. It presents both the classical variational formulation and the finite element formulation of the topology optimization prob-lem. The study specifically addresses the problem of minimizing structural mass under stress con-straints. The specific highlights are made for formulating the problem of topology optimization of agri-cultural machinery mechanical structures. The theory is applicable both for agricultural machinery and automobiles. Originality. This work focuses on the advancement of optimal design theory specifically tailored to address unique challenges in the design of automobile and agricultural machinery structures. To meet these needs, the study develops optimization approaches that integrate the specific mechanical, functional, and economic requirements of automobiles and agricultural equipment. Practical meaning. The practical value of this research lies in its adaptation of existing topology structural optimization problem formulations to address the specific challenges and requirements of the automobile and agri-cultural machinery industry. This adaptation ensures that the optimization solutions are not only math-ematically sound but also practically viable, enabling the design of robust, efficient, and cost-effective heavy machinery components.
Dependence of the effect of pressure on the bearing surface on the pressure in a summer tire of size 225/55 R18
(Харківський національний автомобільно-дорожній університет, 2025) Pysartsov, O.; Писарцов, Олександр Сергійович
During the study of the influence of tire pressure on the bearing surface of M1 category vehicles, it was found that research on modern tire sizes has not been conducted. This can be useful when driving general traffic vehicles on the rough terrain. This served as the motivation for the present study. This article investigates the relationship between internal tire pressure and the pressure exerted by the vehicle on the bearing surface. The issue of optimizing tire pressure is especially relevant for ensuring high passability, reducing stress on road surfaces, and improving handling, especially under operating conditions on soft or uneven terrains such as sand, mud, or snow. Options for influencing the pressure on the supporting surface to increase the cross-country ability of the vehicle and practical solutions for increasing the passability are also considered. The purpose of the study was to determine the relationship between changes in internal tire pressure and the specific pressure exerted on the bearing surface. Originality. An experimental study was carried out according to the algorithm presented in the article on a vehicle of category M1 of general cross-country ability "Opel Grandland 1.5 BHDi" at the level of a concrete surface with Michelin Primacy 3 summer tires of size 225/55 R18 98V installed. Results. It was determined that reducing the tire pressure from 2.1 to 1.6 atmospheres leads to a decrease in bearing surface pressure from 1.37 to 1.08 kg/cm², which potentially improves vehicle passability. The mechanism of influence of car weight and tire contact area with the supporting surface from the pressure value in summer tires of standard size 225/55 R18 is described. An almost inverse proportional relationship between tire pressure and bearing surface pressure was also established. The article presents graphical and analytical dependencies and substantiates the feasibility of reducing tire pressure in the context of vehicle operation under challenging road conditions. Practical value. The results of the study can be applied in the design of wheeled vehicles, as well as in the practical operation of vehicles in off-road conditions.
Diagnostics of Electric Vehicles Using OBD-II: Principles, Capabilities, and Prospects
(Харківський національний автомобільно-дорожній університет, 2025) Hnatov, A.; Arhun, S.; Ulianets, О.; Ivanov, D.; Гнатов, Андрій Вікторович; Аргун, Щасяна Валіковна; Ульянець, Ольга Анатоліївна; Іванов, Дмитро Миколайович
The increasing number of electric vehicles necessitates effective diagnostic methods, as traditional approaches developed for internal combustion engine (ICE) vehicles are not always suitable for electric transport. One of the key diagnostic tools is OBD-II, which allows for obtaining information about the state of a vehicle's electrical systems. However, the accuracy and limitations of this method require detailed analysis. Objective. To explore the possibilities of using OBD-II for diagnosing electric vehicles by analyzing their functional potential, features of data reading and interpretation, and assessing the limitations of this method in comparison with other diagnostic approaches. Methodology. An analysis of the functional capabilities of OBD-II for diagnosing electric vehicles was conducted. An experimental assessment of the accuracy of data obtained using OBD-II in real-time was performed. Diagnostic parameters of the high-voltage battery, inverter, and electric motor were analyzed, as well as the efficiency of energy consumption and regenerative braking. Results. The study confirmed that OBD-II allows obtaining important diagnostic data about an electric vehicle, particularly regarding the state of the battery, electric motor, and other components. However, limitations were identified related to the incompleteness of certain parameters, especially concerning battery cell balancing. This can affect the accuracy of assessing the condition of the high-voltage battery and its remaining capacity. Originality. The article provides a comprehensive analysis of the application of OBD-II for monitoring electric vehicles, differing from traditional approaches focused on ICE vehicles. The possibilities of diagnosing major electrical systems in real-time are evaluated. Practical Value. The results may be useful for electric vehicle owners who wish to independently monitor the technical condition of their vehicles, as well as for auto service centers that use OBD-II in their practice. Integrating OBD-II with more accurate data processing algorithms can improve the efficiency of electric vehicle diagnostics.

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