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The work is aimed at increasing the reliability, accuracy, information content and depth of the process of diagnosing the cylinder-piston engine group. For this, an automated diagnostic system has been developed, which includes a system unit with a monitor, special software for measuring and processing information, a measuring analog-to-digital module, adapters for connecting to the engine. The diagnostic system allows you to record the change in pressure of the cylinder for every degree of rotation of the crankshaft with an error that does not exceed 1.7%. Measurements are performed in test mode, when the crankshaft of the engine is scrolled with a starter, and strain gauges are screwed in place of spark plugs. The measurement results are presented in the form of diagrams, text and digital values. The system also allows you to save, reproduce and transmit diagnostic information in digital, graphic and text form.

Problems of reducing emissions of harmful substances and fuel consumption of the engine are interrelated, since they are mainly determined by the work process. Measures aimed to reducing fuel consumption cause changes, often upwards, toxic compound formation. The fuel and environmental criterion is proposed taking into account the engine operating conditions for a reasonable choice of technical solutions for the comprehensive improvement of fuel economy and toxic level indicators of the exhaust gases. This criterion allows assessing the effectiveness of solutions to improve combustion efficiency, the use of alternative fuels, exhaust gas aftertreatment systems, and other measures.

In the design of gearboxes and transfer boxes of heavy-duty vehicle`s transmissions, sliding bearings are often used as supports for gear wheels. Analysis of the results of statistical processing of gearbox parts failures and transfer boxes of wheeled tractors with a pulling force of 30 kN indicates the need to improve the reliability of the sliding bearings of the gear wheels. Such plain bearings ensure free rotation of the gear wheels in case of the torque transmission absence, and when locked by a clutch, the radial load of the gear wheel is sensed, while operating in the slipping rolling mode. Such units are poorly understood and in the technical literature sources there are no recommendations for their engineering, which often leads to errors when selecting operation gaps and press fitted in gear wheels. The manufacturers of the transmissions assemblies replaced the plain bearings, which in this case are made of metal-ceramic bushes, for roller bearings.

The article considers the actual problem of vehicles fuel efficiency and environmental friendliness increasing. This problem is solved by developing of a new type of hybrid power unit. A feature of this development is that such a hybrid power unit can be implemented in the budget segment of cars. As a result of the study, conceptual solutions for creating a hybrid power unit were developed. The concept is based on the following theoretical provisions. The most economical speed of the hybrid vehicle in the "only electricity" mode lies in the range from 0 m / s to 16 m / s. The further set of speed and movement is advisable to carry out on an internal combustion engine. Mileage in the "only electricity" mode can be in the range from 20 km to 50 km, depending on the energy consumption of the battery. This distance can be chosen by the buyer of the hybrid vehicle depending on the estimated average daily mileage and the cost of the batteries. Traction batteries are charged in three cases.

In connection with the tightening of environmental standards, the leading manufacturers of marine low-speed engines are carrying out intensive work on their conversion to gas fuels. Due to the design features in this class of engines, only internal mixture formation is possible. For the organization of which two different approaches are possible. To date, only two are currently implemented. MAN started production of engines with gas fuel supply to the working cylinder under high pressure at the end of the compression stroke, and WinGD under low pressure at the beginning of the compression stroke. The analysis, performed by the authors, showed, that increasing the pressure before the gas supplying mechanisms to 3.5...6.0 MPa can reduce the residence time of the gas-air mixture in the working cylinder and reduce the likelihood of detonation combustion.

The article is devoted to the study of the efficiency of the system that provides the production of hydrogen-containing gas using a thermoelectric generator and the addition of this gas to the air charge of the spark ignition engine to improve its indicated, effective and environmental performance. The thermoelectric generator is installed in the engine exhaust system and provides the conversion of the exhaust gas thermal energy into electrical energy to power the generator of the hydrogen-containing gas. The results of experimental studies of indicated, effective and environmental performance of the engine with the hydrogen-containing gas added in a wide range of operating modes are provided. Vehicle fuel economy and environmental performance with the developed system for adding the hydrogen-containing gas are forecasted using a mathematical model of the car motion in the driving cycle.

This article deals with the features of the thermal preparation system application on automobile engine, the heating of which to operating temperatures is carried out on petrol, and subsequent operation on liquefied petroleum gas. The main element of the heat treatment system is a phase-transfer heat accumulator, the task of which is to minimize the engine warm-up time and, therefore, reduce petrol consumption on warm-up modes. An information system has been developed (is being used) for remote monitoring and control of the thermal preparation processes of an engine with a thermal accumulator. The results of experimental studies on a passenger vehicle engine under various operating conditions have confirmed the effectiveness of using a phase-transfer heat accumulator to reduce the heating time of the coolant and reduce the consumption of petrol to warm up the engine.

Thermodynamic models based on the volume balance method for calculating the working process of an engine with spark ignition and internal mixture formation are presented. The single-zone model makes it possible to determine the pressure and average temperature of gases in the engine cylinder during the working process. The two-zone combustion model takes into account the change in the volume of the exhaust gases zone and the air-fuel mixture zone. The model makes it possible to determine the pressure of gases in the cylinder and the temperature in the zones under consideration when the air-fuel mixture is distributed over the entire above-piston volume at the moment of ignition. The three-zone combustion model takes into account the change in the volume of the exhaust gases zone, air-fuel mixture zones and air zones when organizing the stratification of the air-fuel charge, allows you to determine the gas pressure in the cylinder and the temperature in the zones under consideration.

The results of this work is allowed to identify a number of cybersecurity threats of the automated security-critical automotive systems, which reduces the efficiency of operation, road safety and system safety. Wired or wireless access of the information networks of the modern vehicles allows to gain control over power unit, chassis, security system components and comfort systems. According to the evaluating criterion of board electronics, the presence of poorly-protected communication channels, the 75% of the researched modern vehicles do not meet the minimum requirements of cybersecurity due to the danger of external blocking of vital systems. The revealed vulnerabilities of the security-critical automotive systems lead to the necessity of developing methods for mechanical and electronic protection of the modern vehicle. The law of normal distribution of the mid-points of the expert evaluation of the cyber-security of a modern vehicle has been determined.

Plane bearings are used as rotating bearings for gear wheels of vehicles transmissions. The design of these units provides for the operation of bearings in two main loading modes: sliding mode (without load transfer) and rolling mode with slipping motion (with load transfer). The mode of sliding bearings operation in the rolling and slipping mode is not sufficiently studied, which makes it impossible to quantify at the design stage the influence of the operating conditions of the vehicle on wear processes, and, therefore, on their reliability. It is necessary to take into account the fact that the condition of the bearing coupling affects the conditions of the gearing. The results of statistical studies of wear and accelerated wearing tests of sliding bearings of gears of a wheeled tractor show the low reliability values of both gear wheels and sliding bearings.

This work delivers a rotordynamics model of a high-velocity impeller of a supercharged engine. This model includes a deformable shaft and deformable disk with blades. The bearings are considered to be compliant rather than rigid. The disk has a cantilever arrangement relative to the elastic supports. The stress-strain state of the rotor system is analyzed within a broad range of the dimensional parameters and the rotational velocities. The critical frequencies are studied for this system as well. It is demonstrated that the first two critical velocities of the cantilever rotor with a massive deformable disk can be modified effectively by appropriate choice of the distance between the supports and their stiffness. As a result the operational range of the rotating velocity can be detuned from dangerous resonance.

The bulk of automobiles are equipped with ABS currently. Having of automatic devices that prevent vehicle wheels from locking and skidding does not require consideration of the normal reactions on the front and rear vehicle axles wheels’ changes dynamics. However, ABS malfunction is possible for various reasons, and in this case the braking system must provide the safety vehicle braking. To provide this, it is necessary to return to the problem of choosing the rational braking forces distribution between the wheels of the front and rear axles.

New solutions for actual problems of determination the efficient distribution of braking forces between the axles of the vehicle, and the stability and drivability of two-axles vehicles at service braking are received in the thesis. It permitted for the first time to determine the Law of distribution of the braking forces between the axles, that ensuring straight-running stability of two-axle vehicle at service braking, to obtain the ideal characteristics for the braking system of two-axle vehicle at service braking and to determine possible values for the distribution of braking force on the front axle. The drivability criterion at service braking obtained further development; it is offered to use boundary at gripping front or rear wheels angular vehicle acceleration on the road.

The article deals with experimental and theoretical researches of hydraulic processes in a system of accumulator fuel supplying (Common Rail) during the diagnosing while the vehicle idling and during the acceleration. The aim of the work is to assess the efficiency of the offered diagnosing technique as the point of view of cutting-down time for troubleshooting and as the point of view of increasing reliability of failure localization. Feature of the presented approach is that it uses the analysis of fuel pressure fluctuations in the high pressure hydroaccumulator, synchronously with the analysis of rotary speed of an engine crankshaft and the steering signals on electromagnetic magnets (or piezoelements) of injectors. The technique uniting preliminary diagnosing of Electronic Engine Control (EEC) and components of the vehicle fuel units during the constant remote monitoring process, and deep, detailed diagnosing at a service station is described.

This paper describes research focused upon improved the quality of automobile engine quality. Methods and models were developed for estimating and predicting the technical condition of internal combustion engine (ICE), which provides usage of the decision support making in the search for minimum fuel consumption regimes. We developed models of multi-criterion, multiparametric optimization of energy and material-material characteristics of ICE according to the system approach. The developed methods and models for estimating and predicting the technical state of the functionally interconnected and interacting ICE components are performed taking into account their hierarchy and topologies, energy resource used and the fuel. The cognitive methodology has been used to make engine models researches and analysis. The paper focuses on the fuzzy logic approach applying, considering the indeterminacy, incompleteness and unclear information in the engines operation processes.

The paper describes the process of modeling and optimizing the operating conditions of vehicles for a section of the transport network using simulation tools. The cyphergrams of the transport flow intensities in the transportation hub were built, a graphic model of vehicle traffic in the transportation hub was built, and a transition probability matrix was compiled, which was used to simulate modeling and optimize vehicle operating conditions for the considered transport hub. It is necessary to use simulation modeling software that supports all simulation methods and a powerful built-in library for traffic modeling. The corresponding simulation model was created. With the help of it, modeling in the transport hub selected for research has been carried out and the optimum values of the duration of the phases of traffic light objects have been obtained. It has reduced the average travel time through the site, which is considered in the work, and the number of cars in traffic jams.

The utilization of different types of energy in phase-transitional thermal accumulators and its further use for thermal development of different subsystems of hybrid vehicles enables to significantly increase their operational efficiency. The system of the combined utilization of thermal and electrical energy in phase-transitional thermal accumulators (TA) is offered. To charge TA, it uses thermal energy of exhaust gas, a coolant and motor oil of the internal combustion engine and electrical energy which is utilized by energy recovery system when braking the vehicle. It consists of consecutive stages of heat accumulation when charging TA from different energy sources of the hybrid vehicle, its storage and use for rapid heating of vehicle separate subsystems. The main heat and power characteristics of system components and heat accumulating materials used in phase-transitional TA have been justified.