The article provides an analytical overview of promising technical solutions for gasoline engines of motor vehicles which is aimed at a significant reduction in fuel consumption and CO₂ emissions of the exhaust gases. It is shown that the main development trend gasoline internal combustion engine (ICE) of a conventional vehicle is the growth of turbocharge use, accompanied by an increase in specific power and a decrease in the ICE dimension, as well as by the decrease of fuel consumption and CO₂ emissions preserving at the same time vehicle speed characteristics. The main tendency in improving the efficiency of the ICE is to increase the expansion (compression) ratio up to 13-15 units. To solve the problems of combustion detonation in the near future it is expected to expand and improve the existing technologies (gasoline direct injection, adjustable valve drive, vortex control), as well as to develop new technologies (Miller cycle, variable compression ratio, recirculation of cooled exhaust gases). The ways to improve the gasoline ICE hybrids depend on the degree of electrification of the actuator. With a relatively low degree of electrification of the ICE it is expected to improve starting and vibroacoustics efficiency together with the rise of efficiency by measures characteristic for conventional ICE. The higher the degree of electrification, the more important power, vibroacoustics, size and cost of the engine, while its structure and optimum control provide its high general efficiency. In the long term (after 2025) the probable direction of the further efficiency increase of ICE may be the realization of a lean homogeneous mixture combustion in the low-temperature combustion mode. The implementation of this tendency will depend on the success in the development of efficient and low-cost NO_x reduction technologies of lean burn products, as well as the use of high-speed and self-learning controlling systems.

The work is devoted to the development and investigation of high-efficiency combined power units (CPU) for transport purposes on the basis of energy source (air-aluminum electrochemical generator -AA ECG) and power source (lithium-ion batteries - LIB). In this work the engineering approaches and technical solutions implemented in the creation of the AA ECG and CPU have been described. The results of volt-ampere and discharge tests of AA ECG module are presented, the maximum power of which is 1.5 kW and the specific energy consumption is 270 (W-h)/kg. The scheme of the CPU with two modules of AA ECG has been developed and implemented. Tests of the CPU with an energy capacity of 46 kW-h on the test bench simulating vehicle movement were carried out. For a vehicle weighing 1,800 kg, the distribution of energy flows in the CPU was obtained in the simulation of movement in accordance with the ISO/CD8714 cycle. The cycle energy consumption (183 W-h) was determined as well as the power reserve at one refilling (265 km). An example of CPU installation on the platform of an electric vehicle GEM was given. At a lower cost the combined power units being developed outperform the known analogs in the set of basic energy parameters - specific power and specific energy capacity.

Fuel economy of the vehicle is a very important performance indicator characterizing the road transport operating efficiency. Therefore, its timely monitoring with the purpose of diagnostics is an urgent task. The more the mileage of the vehicle, the worse the technical condition of the accumulator fuel- delivery system (AFDS) and as a result it affects the amount of fuel consumption, but the relationship between these quantities has not been practically investigated. The article is devoted to the experimental study of the technical condition influence of the AFDS vehicles electrohydraulic injectors. Among the available methods for measuring fuel consumption, the preference was given to its direct measurement, which meant the difference in the amount of fuel which passed through the forward and return lines, the volumetric flow was measured by means of sensors with oval gears. The sensors were characterized by high reproducibility of results, stable indicators at high temperature (on average up to 80°C) and sufficient measurement accuracy (1%). The information on the passed way, speed and acceleration of the vehicle was provided by the standard sensor of the angular speed of the anti-lock braking system from the driven wheel operating without a withdrawal. The experiments were carried out both in steady motion and at acceleration of the vehicle on a smooth asphalt concrete cover with a fully depressed fuel delivery pedal. The technical condition of the electrohydraulic injectors had been previously determined in bench conditions, after which they were installed on the vehicle (GAZ-2217) and check-in tests were conducted. The paper presents the test results of a vehicle with a AFDS equipped with injectors both in a nominal technical condition and in a close to limited technical condition, as the most interesting from the diagnostic point of view.

Fire safety issues of vehicles indicate the need for joint efforts of experts in the field of transport safety. The place of fire safety in the vehicle structure is determined on the basis of the technical regulation definition in the automotive industry. The statistics of fires in motor vehicles for 5 years has been collected and analyzed. Particular attention has been paid to the analysis of fires in buses since 2001. The main causes and locations of bus fires were considered. Operating requirements for the fire safety of buses were detailed on the basis of the technical regulations. According to the results of the GRSG expert group, at the World Forum WP.29 a table of the UN Rules was presented which included the issues referring to the overall safety of the vehicle and the rules of technical regulation of high-capacity buses fire safety. The key tendencies and dangerous places requiring additional study were identified at «FIVE» conference. International research results on similar issues were taken into consideration, including tests on evacuation conditions (Hungary), automatic fire extinguishing system (Sweden), as well as advanced composite materials. Vehicle protection against fire by means of automatic fire extinguishing systems was proposed, including special equipped vehicles (wheelchairs, buses for transporting children, vehicles for transportation of money and valuable cargo, vehicles for transportation of dangerous goods). Recommendations for equipping buses with automatic fire extinguishing systems together with methods of testing such systems were made and included in the amendments to UN Regulation N 107. The further development of the UN Regulation N 110 was outlined considering the incidents in the Netherlands and improving the UN Regulation N 118 methods by adding more rigid requirements existing for railway and sea transport. The conclusions contain proposals to improve the situation. The statistics of bus fires with their reference to their occurrence and causes in the Russian Federation was presented and the ways of fire safety further development of the object under study considering international research were suggested.

The issue of increasing the active safety of vehicles, especially buses and freight lorry trains, despite numerous developments in this area, remains relevant for a number of reasons, among which the author calls the constant increase in the fleet, a fragmented approach to the development of active safety systems, and the reverse effect from their implementation. This phenomenon is caused by the desire of drivers to make the vehicle stability as high as possible, reduce the concentration of their attention independent of the general level of their skill. The author summarizes the new interconnections in the “driver - vehicle -road - environment” system, conditioned by the influence of the human factor. An evolutionary analysis of the active safety systems development has been carried out by methods of scientific deduction and induction. The purpose of the work was to determine the functional composition of the innovative active safety system based on the warning method of traffic control, the main positions of which were a complex functional composition, preventive nature of the action and unlimited adaptability to the driver’s actions including the emergency situations in the process of vehicle movement. Organizational and technical ways of solving the human factor problem in the field of road safety have been indicated. Modern problems of development and introduction of vehicles autonomous control, in particular, insufficient accuracy and stability of navigation technologies, the complexity of compiling virtual maps, poor quality of road marking, climatic features, as well as legal and social aspects were formulated. A new classification of active safety systems in four directions of development was made. The basic and additional functions of the traffic control system for vehicles were listed.

For the development of various sectors of the economy and ensuring the defense the effective delivery of indivisible bulky and heavy items whose weight can reach hundreds of tons is of particular importance. A special role in solving this problem is given to convoys, because this kind of goods can be transported on public roads only with the help of them. On off-roads it can be done only partly. In general, the increase in transport efficiency is achieved by increasing efficiency and reducing transportation costs. The efficiency of road trains is determined by their average speed and lifting capacity. However, the possibility of using road trains in difficult driving conditions is significantly limited by the lack of maneuverability and inability of their widespread use in off-road areas. Another factor reducing the efficiency of road trains is the longitudinal sloping of roads. When moving up the hill even a fourwheeled tractor-trailer may have limited motion ability because of the coupling weight coefficient, and, consequently, insufficient traction. To achieve the improved pass ability of the road train it is possible by increasing the number of drive wheels which is achieved through its use as an active trailer. To compare the dynamic characteristics of the road train with passive and active semitrailer a mathematical model of two-chain road train dynamics as part of the four-axle truck and three-axle semi-trailer has been created. The results of theoretical studies of the road train rising motion conditioned by different variants of the drive wheels of the semitrailer were given. The direction of future research is the synthesis of rational law controlling the semitrailer drive system.

Due to the lower cost, smaller size and high reliability the friction couplings are most widely used in automobiles and tractors designs. The article deals with the process of starting and accelerating the vehicle or tractor units equipped with electronic hydraulic control system of friction clutch with speed manual transmission. To start and accelerate smoothly without jerks and heavy loads in the transmission a method of selecting algorithms of the clutch engagement has been developed. The selection of algorithms was done empirically, after which the data were tabulated. As a result, the best algorithm of coupling engagement was chosen. To control the clutch according to the chosen algorithm it was necessary to necessary to make changes in the design of its control system. For this purpose, a hydraulic cylinder was installed in the clutch control system. A mathematical model of the objective function optimization (minimization of the two criteria of quality) and restrictions (the angular velocity of the engine must not be below the tolerable, and the longitudinal acceleration of the vehicle or a tractor unit should not be above the normalized) was adopted together with the method of solving optimization problems. The method was based on the idea of a uniform compromise and it allowed to determine the optimal law of the coupling engagement. The use of automated clutch control option increases productivity and resource of the clutch, and therefore its economic efficiency. Also fuel and lubricants costs were reduced. The payback period of costs of an upgraded tractor or vehicle when compared to the baseline is 1.88 years.

The choice of thresholds of electronic control adjustment of braking systems is oriented at the maximum of φ_x - s_x-diagram. To specify the maximum position of φ_x - s_x-diagram its forms under different conditions should be known. The majority of the vehicle motion modes are determined by the side force. In different cases the lateral force can occur before or after the wheel brake moment. The purpose of the article is to investigate the sequence effect of side force occurrence and the braking torque on the wheel tire grip with a solid road surface and to study the maximum position of φ_x - s_x-diagram. The author has developed techniques to take into account the sequence of appearance of the side force and torque of the wheel when calculating φ_x - s_x-diagrams. The research is based on the hypothesis according to which the proportion of the coefficient of adhesion implemented by the static friction in the contact area in the presence of lateral force is dependent on the proportionality coefficient of static friction. The formulas for the calculation of coupling coefficients for different slide sequence take into account the successive emergence of lateral force and braking torque of the wheel. The formulas are universal and can be applied to all types of tyres, different kinds and conditions of road surface. The forms of φ_x - s_x-diagram were studied at different sequence of side force occurrence and torque of the wheel. The essential influence of lateral force occurrence sequence and the torque of the wheel on friction properties of static and sliding zones of the wheel tire contact with the road and the maximum position of φ_x - s_x-diagram has been established. If the lateral force was prior to the beginning of braking the car (braking at turn, side wind, etc.), the maximum decrease of the friction coefficient was reduced in the preserved horizontal sliding position. If the lateral force appeared after the beginning of vehicle braking (braking while turning, side wind, etc.) its increase will cause reduction of the maximum friction coefficient at sliding displacement to the left. It has been established that the growth of the lateral force value from zero to a weight value led to the peak change of φ_x - s_x-diagrams up to 66% in the direction of smaller sliding. The results obtained can be applied in the creation and implementation of the wheeled vehicle control algorithms in the electronic active safety systems in order to increase traffic safety.

Identification technology applied to wheeled vehicles (WV) neither protects them against deliberate distortion of license plates nor provides the necessary information about the WV if it has not been included into the database before. Informatization and the need to reduce vehicles labor costs put forward a set of requirements to WV identification technologies which nowadays do not meet the technologies applied in Intelligent Transport System (ITS). To meet the ITS needs a Radio Frequency IDentification (RFID) is suggested which together with marking and attached to it updated and accumulated WV operation data includes a multi-stage procedure of the radio frequency scanning. WV electronic marking is supposed to be implemented by placing the identification data in numerous electronic control units installed in the WV and WV RFID tags. It is also suggested to place the registration, purpose, category, equipment, diagnostic norms and safety regulations data together with operating events of WV in the RFID tag and provide them with cryptographic protection in case they are queried by external information system. RFID tags of WV are to be linked with the onboard Local Area Network (LAN) and provide opportunities for renewal and replenishment both of variable registration data of WV and linked with them information. RFID will eliminate labor costs while seeking the data concerning purpose, configuration, diagnostic regulations, WV operating and is to provide automated confirmation of WV admission to the operation, pass or parking. The ability to monitor WV technical maintenance automatically in compliance with the manufacturer's instructions will serve as an instrument of the WV reliability.

The automotive developments of today tend to increase productivity, speed and ecological performance of vehicles. All changes which relate to the increase of cardinality parameters of the internal combustion engine (ICE) together with the use of hybrid drives and powertrain design improvement inevitably lead to the increase of intensity and vibration in wheeled vehicles. Analytical calculations show and experimental studies confirm the presence of alternating loads in the elements of wheeled machines. The number of failures caused by vibration is high in automotive machine building. The elimination of fluctuations in vehicles transmission is an important and urgent problem of modern engineering for the reduction of the cost of machines and additional expenditure on their recovery in the course of operating life. Vibration loading reduction problems of transport vehicles transmission are solved by many domestic and foreign firms. In each case the choice of the means reducing torsional vibrations in the transmission is determined by the specific characteristics of the system and its operating conditions. Experimental evaluation of dynamic loading of the vehicle transmission with a combined power unit (CPU) is conducted as part of the research work. The aim of the study under consideration is the accumulation of experimental data on the vibrational processes in the nodes of a hybrid vehicle drive. The practical value of the work is to evaluate the effectiveness of the proposed torsional vibration damper (TVD). The experimental data can be used to adjust and validate calculation models to determine the dynamic load transmissions of vehicles with CPU. In addition, the article describes the complex of information-measuring apparatus, the succession of preparing and programing of laboratory and road tests for a researched vehicle with a hybrid propulsion system.

The analysis of the development of automatic transmissions (AT) shows the desire of developers to reduce by all possible means the loss of power during its transfer from the engine to the drive wheels. The number of controlled friction elements in the off position is one of the main factors affecting the magnitude of the power losses in the gearbox. The smaller the number of the control elements, the higher the efficiency of transmission. Therefore, the leading manufacturers of AT shifted to the kinematic schemes possessing four degrees of freedom. One of the ways to reduce the power losses in the friction controls is a transition to a non-synchronized gear clutches in planetary transmissions. The gear couplings were first used by the German company ZF in the nine-speed gearbox ZF 9HP. It was found that for the synchronization of gear locking clutches and brakes at a lower gear it was necessary to increase the rotation frequency of the driving shaft of the gearbox by an amount equal to the progressive geometrical denominator between two adjacent gears, while the reduction of rotation frequency resulted in the increase of shifting gear by the same amount. The paper presents a methodology of experimental verification of the theoretical research results on Axiline Super Flow Technologies Group test stand. In the course of the experiment it is supposed to carry out the following research: to evaluate the gear coupling synchronization process during the down and up gear shifting in the ICE constant throttle position and during its opening. The presented technique allows to check study results and the possibility to use non-synchronized gear clutches in automatic planetary gearbox as controlling elements.