Mobility and Vehicle Mechanics

15-25

Authors: Sonja Kostić, Zorica Đorđević, Milosav Đorđević, Saša Jovanović

The distribution of the external radial load on rolling bodies of bearing is uneven. This is a statically undefined problem, so for the analysis of load distribution beside equilibrium conditions need to be introduced and supplemental one which are based on the relationship between the contact deformation of the contact parts and loads. The unevenness of the distribution is greater considering the influence of the inner radial clearance. Purpose of the paper is to determine the load transmitted by the most heavily loaded rolling body as well as the other rolling bodies, used analytical and numerical approach.

45-53

Authors: Slavica Mačužić, Igor Saveljić

A seat belt is a vehicle safety device designed to secure the occupant of a vehicle against harmful movement that may result during a collision or a sudden stop. In recent years, serious and fatal accidents have decreased in number. The reason is that more and more people begin to understand the importance of using safety belts. When driver makes a sudden stop, the speed from the car causes driver to hit the seat belt with significant force. That force saves life, but can leave passenger with bruises, scrapes and fractures. In this paper the influence of different force values on the abdomen of the driver by the seat belt is analyzed. As a result, the different speed values of the car, due to sudden braking, give different values of force which the seat belt acts on the driver.

17-27

Authors: Slobodan Mišanović, Predrag Živanović, Dušan Savković, Pavle Krstić, Slobodan Ivanov, Slobodan Stević

Since, September 1, 2016, new line EKO 1 is established in Belgrade, where are five E-buses in operation. What are the experiences in exploitation in terms of realized transport, maintenance, electric consumption, environmental benefits as well as the satisfaction of passengers, who use the line EKO 1, are the subjects of this paper. In paper will also present future plans for further expansion of the network line in Belgrade, where the electric buses will operate.

39-47

Authors: Boris Stojić, Aleksandar Poznić, Nebojša Nikolić

Vibrations of agricultural tractors and other off-road vehicles are mainly excited through uneven ground encountered by such vehicles. Thereby tire acts as geometrical filter that transforms short-wavelength road undulations into effective excitation profile of milder geometry. Being geometrically conditioned, this filtering behaviour depends on tyre radial deflection i.e. contacts length. In this paper examination of sensitivity of filtering behaviour to contact length change is described and results are presented.

27-42

Authors: Goran Pejić, Marko Bunjevac, Matija Pečet, Zoran Lulić

Despite significant improvements in vehicle technology in recent years, vehicle emissions remain a major influencing factor on air quality. Although air quality in the City of Zagreb is still relatively acceptable, official standards, i.e. limiting values are under threat. More than ever, policymakers are actively exploring options for new vehicle emission control and local fleet management policies, as well as the new monitoring technologies to support these activities. The goal of the research was to assess the influence of the introduction of Low Emission Zone on the total emission from the road traffic in the City of Zagreb. To make a model of emissions from road traffic, emissions on selected roads in the City of Zagreb using measured traffic activity data and adequate vehicle fleet characteristics description are calculated. Traffic activity data were obtained from traffic study of the City of Zagreb, while vehicle fleet characteristics are extracted from the database maintained by Center for Vehicles of Croatia and the Ministry of the Interior of the Republic of Croatia. The database contains all the data collected during the homologation process of the vehicles registered in Croatia as well as the data collected during the vehicle periodical technical inspection.

59-71

Authors: Isak Karabegović, Ermin Husak

In the last ten years, digital technology has significantly contributed to the change of people's lives worldwide, because its application has caused a rapid transformation of all aspects of human life, and especially fast transformation in the design, production, operation and maintenance of the production system, which caused an unexpected jump in productivity. It can be said that fourth industrial revolutions on-going process, which can be labelled a variety of ways, such as "intelligent factory", "smart industry" or "advance manufacturing". Development of the digital technologies in the last twenty years has introduced us from third in the fourth industrial revolution. The first time the term “Industry 4.0” appears in the Germany in year 2011 whose government promotes automation of production processes by introducing digital technologies. Germany is one of the most technologically developed countries in the world and it is logic that this revolution begins there. This example follows the other countries in the world. Fourth technological revolution depends on a number of new and innovative technological achievements. It is necessary to integrate production processes in all production phases and further applications by using ICT technologies for digitalization. The automation of production processes must include advanced sensors and intelligent robots that can be self-configured to be able to make specific product. It is necessary to collect large amounts of data to be analysed and used in the production processes. It is also necessary to realize network communication (include mobile and internet technology) between machines in the production process, the production system and the operator, as well as suppliers and distributors. Application of previously mentioned leads to the intelligent manufacturing processes that have a wide range of change of production processes. To intelligent process we can come only by applying intelligent industrial robots because they represent one of the cornerstones of the fourth industrial revolution. In this paper an analysis of industrial and service robot application in production processes. With the implementation of digital technology, robot technology and other advanced technology we, as a society, strive for intelligent automation, and intelligent factories, and thus create a society in which wealth, created through the strengthening of global competitiveness, will serve for resolving social issues in society.

13-25

Authors: Saša Mitić, Ivan Blagojević

Motor vehicle industry is nowadays exposed to numerous serious challenges, mostly related to its influence to environment. Motor vehicles during their life cycles affect the environment in several aspects: through consumption of energy and other resources, through production of waste in design process and usage, and through disposal at the end of their life cycle. First two aspects are in consideration for many years and there is noticeable improvement in reducing the effects, but vehicle disposal at the end of life cycle is relatively new area of research. This paper presents main items of international legislative related to end-of-life vehicle recycling process, as well as responsibilities of all participants in this process, from producers to dismantlers and landfills. Also, current legislation in Serbia is presented, with suggestions and ways for future improvement. At the end, concrete data of recyclability and reusability rates for some vehicle models are given, approving the positive effects of applied legislation on vehicle influence to the environment.

43-52

Authors: Satoru Furugori, Takeo Kato, Yoshiyuki Matsuoka

Timeaxis design is a design concept that incorporates the concept of time axis into design theory and methodology. Under this design framework, different methods, such as models those who integrate multiple timescales, those employ identity mapping to describe non-linear and non-steady phenomena and those employ genetic network programing to describe phenomena evolving gradually as times pass, have been proposed. We applied Timeaxis design to develop an automotive safety control system that considers risks at a short timescale (second/minute), medium timescale (hour/day), and long timescale (month/year). This system displays the driving state on the basis of the state of the driver’s vehicle, surrounding vehicles, and driver’s physical conditions, generates the vehicle control algorithm on the basis of the driver’s state, and provides driving advice to the driver in real time. With this system, it is possible to correspond to future safety issues such as problems caused by mixing of autonomous vehicles and conventional vehicles, problems caused by reduction in driving skill due to automation of driving and problems caused by the decline in driving ability with aging.

13-25

Authors: Mikhail G. Shatrov, Vladimir V. Sinyavski, Ivan G. Shishlov, Andrey Y. Dunin, Andrey V. Vakulenko

Analysis of different methods of diesel engines conversion for operation on natural gas was carried out showing feasibility of these methods for engines of various applications. The KAMAZ V8 120/120 mm diesel engine was converted to operate on natural gas by spark ignition cycle and Cummins Kama 6L 104/127 mm diesel engine – by gas diesel (dual fuel) cycle. Gas feed and electronic engine control systems were developed for both the methods of engine conversion. For gas diesel version, modular gas feed and engine control systems were developed which could be mounted both on high-speed and medium-speed gas diesel engines. These systems were perfected during engine tests. CR fuel system for the perspective medium-speed D200 6L 200/280 mm gas diesel engine was developed jointly with the industrial partner. A computer model for simulation of engine operation was developed and calibrated on the basis of engine tests and used for the development of gas feed and engine control systems, experimental results analysis and forecasting of the parameters of the medium-speed D200 gas diesel engine. Engine tests of the gas and gas diesel engines demonstrated considerable decrease of CO2 and NOx emissions, practically no soot and lower fuel consumption compared to the base diesel engine.

37-49

Authors: Ivan Blagojević, Saša Mitić

Limited oil reserves and the ecological consequences of its use in motor vehicles impose an increasing need for alternative energy and drives. The use of hydrogen as the fuel of the future is one of the solutions whose commercialization has begun in the past few years. Although its use has no impact on the environment, the production process, which is still expensive, does. Transport and storage of hydrogen, as well as advanced, but expensive technologies for its use, also present additional challenges, which are examined by the authors of this review paper through few topics. The properties of hydrogen, the way it is obtained, stored and transported are presented. Particular attention is paid to the method of obtaining the propulsion energy by combustion or by using different types of fuel cells. The paper also covers some examples of vehicles powered by hydrogen.