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The method of testing vehicles for dynamic position stability has been improved, which makes it possible to assesstheir lateral stability when driving on irregularities. The dynamic stability coefficient is proposed for use as an assessmentcriterion. The application of the developed method allows to obtain an assessment of stability in real time during theoperation of transport means.The structural scheme has been developed to ensure the reliability of the operation of wheeled vehicle, based onreducing the influence of the driver's qualifications as an element of the "driver-vehicle-road conditions" system on itsposition stability, taking into account the results of monitoring the technical condition.To conduct experiments and evaluate the results, the mobile registration and measurement complex (MRMC) wasused to assess and improve the safety of exploitation of wheeled vehicles, taking into account modern means andapproaches. A single-board computer Raspberry Pi version 3B + serves as a platform for the mobile registration andmeasurement complex. The architecture of MRMC is modular; it supports the installation of additional inertial sensors,photo and video fixation devices, GPS, as well as devices compatible with USB. Operating system – Raspbian based onDebian distribution (GNU / Linux).To further automate the process of controlling a wheeled vehicle, the promising scheme for the operation of theregistration and measuring complex with elements of artificial intelligence was developed, which allows, without theparticipation of the driver, to carry out the necessary actions to control it and ensure, including operational safety.The results can be used to assess the suitability and performance of wheeled vehicles.

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The conducted systematic analysis of maintainability indicators allows establishing their connection with other reliability properties and classifying these indicators according to technical and economic criteria. On this basis, the technological component of maintenance and repair, which ensures the provision of spare parts, tools and means of technical condition control, was selected and investigated. Set of indicators that allow to evaluate and standardize the maintainability of means of transport most fully and in accordance with modern requirements is proposed.The dependence was obtained for determining the required number of tools in a set of spare parts, tools and accessories (STA), which takes into account the reliable characteristics of the machine and the characteristics of the process of restoring its operability under real operating conditions.The approach to calculations of rational sets of tool equipment for vehicle machinery is proposed on the example of the chassis of the domestic wheeled tractor KhTZ-17221, the corresponding calculations are performed. The conducted analysis shows that with the existing service system and the level of reliability of the KhTZ-17221 tractors in real operation conditions to ensure the readiness factor within 0.85-0.95, the presence of tools in the equipment kit has a significant impact.The analysis of the obtained dependence shows that in order to quickly eliminate the consequences of the failures of the KhTZ-17221 tractors, it is necessary to have a complete set of tools in the set of STA, provided for in the operating instructions. Otherwise, the operative time for eliminating failures increases, which leads to unjustified downtime of equipment and increased costs for consumers, especially during periods of agricultural work. When increasing the number of tools in the kit of STA to the level regulated by the factory documentation, while maintaining all other parameters, it is possible to increase the readiness factor in real operation from 0.84 to 0.92. That is, the presence of tools significantly increases the efficiency of vehicles using in real operation conditions.The obtained results can be used to improve maintainability indicators

Харківський національний автомобільно-дорожній університет Вплив на потужність двигуна колісної машини механічних втрат при відключенні циліндрів Запропонована методика розрахунку механічних втрат, яка дозволяє з точністю близько 10 % визначати вплив кількості відключених циліндрів на ефективну по-тужність двигуна, потужність механічних втрат і механічний ККД. Встановлено, що при відключенні половини циліндрів: номінальна потужність станове 35-40 %, розбіжність експериментальних і розрахункових результатів коефіцієнта зміни потужності механічних втрат не більше 8 %; розбіжність розрахункових і експериментальних результатів коефіцієнта навантаження по потужності не більше 5 %; механічний ККД при завантаженні 48 % підвищується на 7 %. Із збільшенням кількості відключених циліндрів в двигуні, збільшується потужність механічних втрат та зменшується механічний ККД. Встановлено кореляційний зв'язок механічного ККД та ефективної потужності двигуна: із збільшенням кількості відключених циліндрів (факторна ознака) в двигуні, збільшується потужність механічних втрат (результативна ознака) та зменшується механічний ККД.