Introduction (problem statement and relevance). Simulation modelling and calculation of the thermal state of electric motors are important in the current conditions of automotive industry development. One of the key components of electrified vehicles is an electric motor, the specific indicators of which reach 10 kW/kg for electric vehicles. Certainly, such high performance indicators are impossible without innovative approaches to modelling and application of advanced materials.

The purpose of the study is to analyse the thermal processes inside the electric motor and to determine the heat transfer coefficient.

Methodology and research methods. The methods used are based on the fundamental principles of heat- and-mass transfer, electrical engineering, as well as methods of engineering analysis and research tests. Scientific novelty and results. Based on the research results, a verified thermal one-dimensional (1D) model of the electric motor has been obtained. The developed model showed an error of less than 10% based on the results of road cycle in-vehicle tests. Unlike the existing approaches based on simplified stationary thermal diagrams or computationally expensive three-dimensional (3D) CFD models, this work has developed a verified non-stationary one-dimensional (1D) model of the thermal state of an electric motor using the Matlab/Simulink (Simscape) environment. The model takes into account the interrelated processes of thermal conductivity, convective heat exchange in the liquid cooling system and forced rotor convection, as well as the dependence of the coolant’s thermophysical properties on temperature and flow rate.

The scientific novelty of the approach lies in the combined consideration of thermal processes in the active parts of the electric motor and in the cooling system of the model suitable for integration into the overall vehicle thermal system.

Practical significance. Current challenges in the automotive industry are aimed at improving specific indicators which inevitably leads to the necessity to solve heat dissipation problems. This model allows assessing the thermal state of windings and other components during vehicle operation; it can be integrated into a more general or comprehensive model, for example, a model of vehicle thermal management or traction drive, and also allows obtaining data on the thermal state of the system with high convergence of results without conducting preliminary field tests.

Introduction (problem statement and relevance). The paper suggests a physically substantiated method for recommending the optimum speed that minimizes short-term forecast fuel consumption taking into account constraints in terms of acceleration, speed limits and the traffic scene. The method relies on synchronized CAN telemetry and a digital terrain model, as well as a regression model identifying the reduced coefficients of the fuel consumption model. Validation on real routes showed fuel economy without increasing the travel time.

The purpose of the study is to identify and verify a procedure to form speed settings (commanded speed levels) that allows reduction in fuel consumption of heavy trucks under real operating conditions.

Methodology and research methods. The suggested approach is structured into three interconnected stages: 1) regression identification of parameters of a physically substantiated fuel consumption model based on properties extracted from CAN telematics and the digital terrain model; 2) short-term convex optimization of speed settings using L2-regularization; 3) introduction of perceptual constraints formed by the YOLO computer vision module, which ensures compliance with safety requirements and conformity of recommendations to the current road situation.

Scientific novelty and results. A stable “properties → coefficients” fit model has been obtained ensuring precise fuel consumption forecasts; fuel economy has been shown on routes while complying with road scene constraints.

Scientific novelty consists in combination of a physically reasonable regression model with perception and online optimization of speed settings.

Practical significance. The method is implemented in a standard ECU/mini-PC requiring only CAN and cartographic data; it generates recommendations for HMI in the form of a number and color scale, or manages intelligent cruise control. This allows reduction in consumption without worsening the travel time.

Introduction (problem statement and relevance). Increasing the level of vehicle passive safety remains one of the priority tasks of the modern automotive industry despite the continuous improvement of designs and systems. It is particularly difficult to ensure protection of the driver in case of side or lateral collisions, which, having a relatively low probability of occurrence, are characterized by extremely severe consequences due to the minimum area of absorption of impact energy. In such conditions, human safety depends in many respects on operational efficiency of passive safety system active elements (seat belt and side airbags).

The purpose of the study is to assess the degree of impact of passive safety system active elements on the index or indicator (total score) of passive safety of a passenger car.

Methodology and research methods. In order to conduct virtual testing, a comprehensive numerical modelling approach is used. The finite element method is used to reproduce the process of vehicle body deformation at the pole side impact as well as to analyze the anthropomorphic dummy interaction with the vehicle interior elements and the seat belt. The corpuscular particle method is used for high-precision modelling of the process of side airbags gas filling and interaction with the dummy.

The scientific novelty and results lie in development of a point rating system assessing the passive safety according to a set of the pole side impact injury criteria established by UN Regulation No. 135 and in assessment of each passive safety element contribution to reducing driver’s pole side impact injuring.

The practical significance consists in creation of a tool (point rating system) for quantitative assessment of passive safety at a pole side impact, which allows aligning different injury criteria into a single integral index for comprehensive assessment of driver injuring.

Introduction (problem statement and relevance). The paper deals with the issue of development of a new procedure for testing functionality of ADAS radars under real operating conditions of the Russian Federation due to changes in test objectives.

The purpose of the study is to develop a new test procedure to collect additional experimental data in order to derive analytical dependences reflecting actual processes.

Methodology and research methods. The study uses the method of comparative testing for vehicles with different radar positions. A new scheme for arranging the vehicles under test in a group during the experiment is developed, which excludes dependence of snow and dirt layer accumulation on a certain lead vehicle (LV).

Scientific novelty and results. It is proved that it is necessary to conduct measurements of not only the snow and dirt layer obstructing ADAS radar operation, but also of other physical parameters influencing the layer thickness dynamics. The roadway condition factor concept for highways is introduced, which characterizes the amount of snow and deicing chemical agents (DCA) on the road. The arrangement or location order of vehicles under test on the roadway is changed in order to exclude the influence of a certain LV on the rate and degree of contamination of the following vehicle under test. An analytical dependence is derived, which determines the order of vehicle rearrangement during the experiment. Based on the obtained experimental data, analytical dependences are derived, which characterize the real processes of snow and dirt layer build-up on operational surfaces of variously located ADAS radars.

The results of using of the obtained dependences in comparison with the experimental data will be published in a separate paper.

Practical significance. A design is developed for installing a quick-detachable test plate located at the same height above the road surface irrespective of the height of position of the default or standard ADAS radar. The possibility and necessity of measuring not only the snow and dirt layer thickness on the test plate surface, but also of its weight is proved in practice.

Reliable rear visibility is of great importance for ensuring road traffic safety. Under modern
conditions, various technical solutions are applied to meet these requirements. However, modern solutions
have both positive and negative aspects. International requirements for rear visibility parameters are
changing along with development of technical innovations. The purpose of the study is outreach activities
regarding devices for indirect vision, requirements for them, and highlighting of the advantages and
disadvantages of various designs. The anticipated results are to communicate to the reader correct
interpretation of requirements of UN Regulation No. 46 “Uniform provisions concerning the approval
of devices for indirect vision and of motor vehicles with regard to the installation of these devices” and
Directive 71/127/EEC regarding the requirements for devices for indirect vision of all classes and their
in-vehicle installation.

Introduction (problem statement and relevance). The global transition to the low-carbon economy stimulates development of hydrogen transport. The key advantage of hydrogen fuel cells (FC) over lithium-ion batteries is high specific energy, which potentially extends the cruising range and increases the loading capacity of vehicles. The relevance of the paper is determined by the necessity to optimize hybrid vehicle FC-based powertrains in order to increase their energy efficiency, which depends heavily on the system configuration.

The purpose of the study is to analyze the impact of a hybrid fuel cell based powertrain and traction battery configuration on the vehicle cruising range under conditions of the urban and intercity (highway) driving cycles.

Methodology and research methods. In order to achieve the purpose, a mathematical model of vehicle driving is developed, which includes the powertrain power balance and models of the following components: proton exchange membrane fuel cell, traction battery and hydrogen storage system. The simulation is conducted for the urban and intercity routes with variation of the key powertrain parameters: fuel cell maximum power, traction battery capacity and weight of the hydrogen being transported.

Scientific novelty and results. It is found that the optimum powertrain configuration depends crucially on the route type. For the urban cycle, the maximum cruising range (1433 km) is achieved in case of a configuration with a large-capacity traction battery (40 A·h) and low-power FC (40 kW). For the intercity cycle, the key is to increase the power of fuel cells (up to 160 kW), which allows lowering of requirements for the traction battery and increasing of the weight of the hydrogen transported, providing the cruising range of up to 833 km.

The scientific novelty consists in the method of increasing the energy efficiency of a hydrogen vehicle, taking into account the impact of the weight of components when analyzing various powertrain configurations.

Practical significance. The research results allow development of more efficient configurations of powertrains for hydrogen transport optimized for specific operating conditions. This promotes powertrain weight decrease, cruising range extension and, as a result, increase in economic feasibility and environmental efficiency of hydrogen vehicles.

Introduction (problem statement and relevance). The use of ground robotic vehicle systems in rescue units and in certain civil fields is especially in demand when there are threats to human life. The global practice confirms this completely. However, the use of such vehicle systems is often limited due to unsatisfactory combination of their technical and consumer properties. Therefore, defining the optimal concept for development of a robotic special transport vehicle based on assessment of experience in creating and operating various ground robotic vehicle systems and conducting special operations is a vital and relevant task.

The purpose of the study is to define the concept (requirements) for developing the robotic special transport vehicle.

Methodology and research methods. The article uses the method of analytical review, i.e. a critical analysis of sources, in some of which the authors of the article were direct participants or performers of works.

Scientific novelty and results. Generalization and analysis of the experience in creating and operating ground robotic vehicle systems and conducting special operations. The conditions of use and the main requirements for the new object – the robotic special transport vehicle – have been determined, which appear to be optimal for development and intended application.

Practical significance. The proposed ground robotic vehicle system concept will be taken into account when creating a family of robotic special transport vehicles in the interests of rescue units of EMERCOM of Russia (The Ministry of the Russian Federation for Civil Defence, Emergencies and Elimination of Consequences of Natural Disasters) and certain civil fields.

Introduction (problem statement and relevance). Hydrogen as an energy carrier was proposed more than 200 years ago, but to date, there have been ongoing disputes about the feasibility of its application in motor vehicles. Discussions on this issue are contradictory, ranging from enthusiastic assessments of the “hydrogen” transition to quite critical assessments of its advantages. In this regard, it seems appropriate to evaluate the positive and negative aspects of the use of hydrogen in one of the most intensive areas of energy consumption, i.e. in automobile transport. The use of energy carriers in this capacity has a number of features, including mobility, specified lifetime and non-stationary nature of consumption. Based on these conditions, the requirements for the systems of filling, storage, transportation and consumption of any on-board energy carrier, including hydrogen, are formed. Quite a lot of attention has been paid to this issue, but considering the high dynamics of hydrogen technologies development, it is necessary, if possible, to promptly monitor these changes and timely assess the consequences of their implementation, including those in automobile transport.

The purpose of the study is to present and evaluate the current state of development of hydrogen storage and transportation systems, taking into account the specifics of automobile transport operation.

Scientific novelty and results. Critical assessment of present-day technologies of hydrogen storage and transportation, with the conclusion that it is inexpedient and untimely to switch to hydrogen power systems of present-day vehicles.

Methodology and research methods. Analysis of literature sources and references in terms of hydrogen and its storage systems from the perspective of feasibility of consumption by motor transport.

Practical significance. Recommendations to reduce efforts into the applied use of hydrogen in transport.

Introduction (problem statement and relevance). The article is devoted to analysis of national standard GOST R 58139-2024 “Quality management systems. Requirements for automotive organizations” which had been developed by Certification Association “Russian Register” and came into force on 01.05.2025. The text of the article contains comparative assessment of requirements of the standard with requirements of international standard IATF 16949:2016 “Quality management system requirements for automotive production and relevant service parts organizations” (hereinafter referred to as the IATF standard) which is currently the main regulatory document establishing requirements for quality management systems for automotive organizations. The domestic standard is considered comparable to the latter in terms of scope and merits of requirements for quality management systems which can ensure improvement of production management processes at enterprises and organizations manufacturing motor vehicles and their components, and influence their ability to continuously deliver products and/or services which meet the customers requirements.

The purpose of the study is to increase the standard efficiency, recommendations for improvement of requirements for quality management systems for automotive organizations.

Methodology and research methods. Benchmarking (comparative analysis).

Scientific novelty and results. Comparison of the requirements of the latest (new) current version of the domestic standard with the requirements established in the international standard IATF.

Practical significance. The practical significance consists in recommendations on inclusion of new requirements and improvement of already existing requirements into subsequent versions of the domestic standard.

Introduction (problem statement and relevance). Based on the results of previously conducted practical studies of chemical composition of welded seams and near-weld areas, hardness and structure of welded joints of dissimilar pearlitic steels 45 and 17GS when manufacturing driving axle casings of off-road vehicles as well as static and fatigue testing, it has been proposed to improve the welding technological process. However, in order to fully reveal the essence and reasons for the positive effect of the results of the previous studies and suggested technological process, in this paper, a computational analysis of temperature fields or patterns and their distribution within the welded joint areas, analysis of changes in the heated metal volume of welded joints, comparison of the results obtained with the studies performed earlier have been conducted and overall conclusions have been formulated.

The purpose of the study is to determine the effect of metal volume change in welded joints of dissimilar pearlitic steels on structural and phase transformations by calculating the temperature patterns distribution.

Methodology and research methods. The paper uses theoretical foundations of mathematical modeling of the theory of thermal processes and a specialized program for calculating properties of welded joints developed according to the methodology of the Bauman Moscow State Technical University.

Scientific novelty and results. The difference in temperature ranges of phase and structural transformations in steels 45 and 17GS is caused by their thermophysical properties. The cooling process when welding these steels with each other is accompanied with volume increase making upon that mutual deformation impact resulting in that austenitic transformations occur at higher temperatures. As a result, self-tempering of transformation products and relaxation of welding stresses occur.

Practical significance. The methodology and results presented in this paper may be used to predict properties of welded joints from other grades of steels.