Inertial evaluation of the tyre-road interaction during emergency braking An improved method of evaluation of the parameters of braking efficiency in vehicles of M1 category has been proposed for expert examination of motor vehicle accidents. This method is based on the control of parameters which are able to significantly influence the friction processes in the contact tyre-road area. These parameters were discovered in the course of analysis of theoretical approaches to the evaluation of the quality of tyre-road interaction, analytical formulas used for evaluation of the main braking parameters (deceleration, stopping distance) as well as for experimental evaluation of parameters of inertia braking efficiency. The generalization of study results showed that existing expert methods of evaluation of the parameters of vehicle motion during emergency braking do not take into account the design of modern braking systems, tyres and psychological aspects of control of the braking process by a human operator. After processing experimental data, recommendations have been formed to improve the existing approaches and eliminate the discovered defects. The verification of the proposed recommendations allowed to establish the areas of their efficiency for M1 category vehicles on dry bituminous concrete and confirmed the need to conduct further studies for vehicles of other categories and other types and conditions of road surface within the framework of the developed general approach.

The paper presents a method for calculating normal reactions of the road bearing surface along the axles of a multi-axle wheeled vehicle, upon which it is possible to construct the adhesion utilization curves for all vehicle axles, considering that both independent axles and axles combined in balancing trolleys are present in the vehicle suspension. The main idea of this method is developing a universal mathematical model for determining the horizontal coordinate of the center of elasticity (center of rotation) of a multi-axle vehicle body with reference to which the normal reactions along the axles of the vehicle during its braking are determined. In addition, with a known distribution of braking forces, the adhesion utilization curves are plotted. In the overview part, an analysis is given that showed that there is no single methodology or recommendations today regarding determination of normal road reactions on the axles of a multi-axle wheeled vehicle. The developed methodology can be applied in engineering calculations when checking multi-axle wheeled vehicles for compliance with international requirements for brake systems (Appendix 10 to UN / ECE Regulation No. 13). The universality of the proposed methodology allows recommendation for its implementation in the given Rules No. 13. The calculations of the adhesion utilization curves made on the example of a 4-axle vehicle showed that consideration of the design features of a multi-axle wheeled vehicle suspension significantly affects the nature of the geometry of the adhesion utilization curves within the permissible limits specified by UN / ECE Regulation No. 13 (Appendix 10).

An assessment of modern trends in the development of intelligent traffic management systems and their role in ensuring the efficiency of the functioning of transport networks was carried out. The processes of introducing technologies for expanding the flow of processed data into existing intelligent transport systems (ITS) that ensure an increase in the speed of information transmission in them have been determined. The classification of information sources that become available when the ITS transitions to the 5G standard and provide a basis for the implementation of technologies for avoiding extraordinary situations in transport networks is given.Existing methods of improving the efficiency of the city's transport network are mainly aimed at ensuring the ability of ITS to predict traffic flows. These include statistical and nonlinear methods, simulation-based methods, artificial intelligence methods, and combined methods. The implementation of these methods is achieved by increasing the information flow coming from the system. A comparison of these methods revealed that they can generally make predictions with high accuracy, however, regardless of the chosen standard, some of them are already at the peak of their potential in terms of application in ITS, and the rest still have room for development.The suitability of the forecasting method for working in real-time conditions is a significant advantage in ensuring effective management of traffic flows, allows to increase the stability of the transport network and the efficiency of the ITS, and has a positive effect on the level of traffic jams, road safety and ecological impact on the environment. The most promising in terms of a quick and flexible solution to an extraordinary situation are models with the use of artificial intelligence or a combination thereof, based on deep learning algorithms, which have proven their importance in predicting the results, making decisions regarding traffic flow forecasts and ensuring the elimination and avoidance of traffic jams based on the passage of vehicles through the intersection depending on the length and duration of the traffic light signals.

The article investigates the energy efficiency of motor-transmission units when using internal combustion engines with different numbers of cylinders. Transmissions, those in a unit with piston internal combustion engines are loaded with uneven torque, which is the cause of torsional vibrations of their parts. Torsional vibrations create additional dynamic loads on the transmission elements, and also reduce its efficiency. To ensure a high level of energy efficiency of the engine-transmission unit, the elastic-inertial parameters of the transmission must be matched with the amplitude-frequency characteristics of the torque of the installed engine. When replacing a serial internal combustion engines with an engine with output characteristics different from the prototype, it is necessary to assess the vibration resistance of the modernized engine-transmission unit, which was done in this work. As a criterion for vibration resistance of the modernized machine unit, the cyclic elastic efficiency of the transmission was used. This factor takes into account the natural frequency of the transmission input shaft, as well as the amplitude and frequency of vibration of the engine torque. The decisive influence on the vibration characteristics of the engine is exerted by the rotational speed of its crankshaft and the number of cylinders. When conducting a comparative assessment of the energy efficiency level of the modernized engine-transmission unit, it was assumed that before the modernization the transmission was in a unit with a single-cylinder internal combustion engine. As a result of the study, the conditions for ensuring the vibration resistance of engine transmission units have been determined, a method has been developed for comparative analysis of the energy efficiency indicators of engine transmission units with different numbers of internal combustion engine cylinders, and possible ways to increase the energy efficiency of engine units of cars and tractors during modernization with a change in the number of internal combustion engine cylinders are indicated.

При вирішенні задач автотехнічної експертизи дорожньо-транспортних пригод (ДТП) прийняття рішень відбувається в умовах неповноти інформації, тобто в умовах невизначеності. В процесі прийняття рішень виникають різні види невизначеності в залежності від причин її появи : кількісна, інформаційна, вартісна, професійна, обмежувальна, зовнішнього середовища. Крім того, невизначеність може мати стохастичну або нечітку природу. Відсутність єдиного методологічного підходу щодо оцінювання та мінімізації впливу невизначеності на результати автотехнічної експертизи ДТП може спричинити значну похибку визначення досліджуваних параметрів. Мета роботи полягає в узагальненні та розвитку існуючих підходів щодо оцінювання невизначеності методологічного забезпечення автотехнічної експертизи та мінімізації суб'єктивності формування експертних висновків в процесі встановлення обставин виникнення аварійних ситуацій. Розглянуто структуру формування невизначеності та методи її оцінювання при вирішенні задач автотехнічної експертизи ДТП. Показано, що процес прийняття рішень в автотехнічній експертизі ДТП слід розглядати не тільки як детермінований, але і як стохастичний та нечіткий процес, який потребує застосування синтезу детермінованих, імовірнісних, регресійних та нейро-нечітких моделей для врахування більшості факторів, що впливають на зменшення невизначеності при формуванні експертних висновків. Запропоновано оцінювати невизначеність методологічного забезпечення автотехнічної експертизи ДТП за показниками узагальненої інформаційної ентропії, яка не є власною властивістю прийнятої системи автотехнічної експертизи ДТП, а залежить від способу опису цієї системи. Розроблено метод нормованої ентропії, який, на відміну від існуючих, є універсальним інструментом для оцінювання композиційної невизначеності (композиції стохастичної і нечіткої невизначеності), характерної для цьного виду задач. Показано, що врахування стохастичної та нечіткої невизначеності, дозволяє звузити діапазони можливих рішень при проведенні експертизи на 20 %, а порівняно з детермінованим підходом суб'єктивність формування експертних висновків в процесі встановлення обставин виникнення аварійних ситуацій зменшується на 46-48 %.