Saša Mitić - Academia.edu (original) (raw)
Papers by Saša Mitić
Mobility and Vehicle Mechanics, 2021
The current state of vehicle technology development has been characterized by the production of a... more The current state of vehicle technology development has been characterized by the production of a very wide range of different types and categories of vehicles. Modern vehicles are characterized by a great complexity of fitted parts and mechanisms. These facts inevitably lead to the intensive development of legislation that cover the entire field of the automotive industry, as well as its harmonization at the international level. From the very beginning of harmonization, Yugoslavia has played a very active role in the development and implementation of the Regulations adopted within the United Nations, the Economic Commission for Europe. As the legal successor, Serbia continued on that path, but due to the situation in the previous 30 years, the activities within the harmonization of regulations have been significantly slowed down, primarily with the European legislation. The paper presents the current state of harmonization of regulations in Serbia with European legislation, as well as certain inconsistencies that occurred during the application of national regulations and performed comparative analysis. Also, an overview of the plan for harmonization of legislation has been given, and some examples of noncompliance are pointed out, which should be overcome with the proposed harmonization plan.
FME Transactions, 2013
This paper demonstrates the approach to determination of cornering stiffness as the most importan... more This paper demonstrates the approach to determination of cornering stiffness as the most important parameter of motor vehicle steering and stability systems through integration of empirical models and real exploitation parameters. The approach is based on the analysis of a tire mathematical model, identification of key real exploitation parameters and integration of a mechatronic system for tire load monitoring. Measurement of tire load and subsequent integration of measured values into developed software module provide a precise definition of cornering stiffness for a certain vehicle and road contact patch. This research assumes integration of a mathematical model and mechanical, electronic and information technologies with the aim of comprehensive understanding of tire behavior in terms of cornering stiffness determination.
Journal of Vibroengineering, 2016
Specific functional requirements for firefighting vehicles have resulted in stricter exploitation... more Specific functional requirements for firefighting vehicles have resulted in stricter exploitation regimes and frequent off-road use. Current practice appoints the problem of the strength of a superstructure’s modules, which are very different in terms of torsional rigidity. It is important to say here that there are no unambiguous manufacturer’s guidelines for bodybuilders to complete a firefighting vehicle. In such circumstances, the identification of the dynamic behaviour of modular firefighting superstructures further gains in importance. Developed numerical-experimental approach for identification, analysis and optimisation of the dynamic behaviour of modular firefighting vehicle superstructures is shown. Experimental part of this method is based on excitation of superstructure physical models with, for this purpose specially developed mechanical exciter. Also, natural frequencies of structures, important in terms of resonant zones, are obtained using bump test and FFT analysis....
Mobility and Vehicle Mechanics, 2018
Motor vehicle industry is nowadays exposed to numerous serious challenges, mostly related to its ... more 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.
Tehnicki vjesnik - Technical Gazette, 2016
Original scientific paper This paper focuses on the identification of failure causes of a bolted ... more Original scientific paper This paper focuses on the identification of failure causes of a bolted joint used for the bedding of a primary column of an aerial platform. The tests conducted to determine chemical composition and mechanical properties have confirmed the 12.9 grade of the bolts. Also, mechanical properties tests and metallographic examination did not indicate any hidden defects caused by heat treatment (e.g. decarburisation etc.). On the other hand, visual and metallographic examination of cross-section as well as electron microscope scanning confirmed fatigue fracture of the bolts. Therefore, further analyses were done to check the dimensioning and the installation of the bolts. The effects on stress states in the bolts are presented from the standpoint of rated operating regimes, stiffness of joined elements, lubrication conditions of thread surfaces and temperature incompatibility between the bolts and elements being joined. Pre-tightening torque value incompatible with lubrication conditions was found to be the main factor that led to high stress values that initiated and later intensified the fatigue process which ended in fatigue failure of the bolts.
Strojniški vestnik – Journal of Mechanical Engineering, 2011
Mobility and Vehicle Mechanics, 2018
Limited oil reserves and the ecological consequences of its use in motor vehicles impose an incre... more 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.
Mobility and Vehicle Mechanics, 2021
The current state of vehicle technology development has been characterized by the production of a... more The current state of vehicle technology development has been characterized by the production of a very wide range of different types and categories of vehicles. Modern vehicles are characterized by a great complexity of fitted parts and mechanisms. These facts inevitably lead to the intensive development of legislation that cover the entire field of the automotive industry, as well as its harmonization at the international level. From the very beginning of harmonization, Yugoslavia has played a very active role in the development and implementation of the Regulations adopted within the United Nations, the Economic Commission for Europe. As the legal successor, Serbia continued on that path, but due to the situation in the previous 30 years, the activities within the harmonization of regulations have been significantly slowed down, primarily with the European legislation. The paper presents the current state of harmonization of regulations in Serbia with European legislation, as well as certain inconsistencies that occurred during the application of national regulations and performed comparative analysis. Also, an overview of the plan for harmonization of legislation has been given, and some examples of noncompliance are pointed out, which should be overcome with the proposed harmonization plan.
FME Transactions, 2013
This paper demonstrates the approach to determination of cornering stiffness as the most importan... more This paper demonstrates the approach to determination of cornering stiffness as the most important parameter of motor vehicle steering and stability systems through integration of empirical models and real exploitation parameters. The approach is based on the analysis of a tire mathematical model, identification of key real exploitation parameters and integration of a mechatronic system for tire load monitoring. Measurement of tire load and subsequent integration of measured values into developed software module provide a precise definition of cornering stiffness for a certain vehicle and road contact patch. This research assumes integration of a mathematical model and mechanical, electronic and information technologies with the aim of comprehensive understanding of tire behavior in terms of cornering stiffness determination.
Journal of Vibroengineering, 2016
Specific functional requirements for firefighting vehicles have resulted in stricter exploitation... more Specific functional requirements for firefighting vehicles have resulted in stricter exploitation regimes and frequent off-road use. Current practice appoints the problem of the strength of a superstructure’s modules, which are very different in terms of torsional rigidity. It is important to say here that there are no unambiguous manufacturer’s guidelines for bodybuilders to complete a firefighting vehicle. In such circumstances, the identification of the dynamic behaviour of modular firefighting superstructures further gains in importance. Developed numerical-experimental approach for identification, analysis and optimisation of the dynamic behaviour of modular firefighting vehicle superstructures is shown. Experimental part of this method is based on excitation of superstructure physical models with, for this purpose specially developed mechanical exciter. Also, natural frequencies of structures, important in terms of resonant zones, are obtained using bump test and FFT analysis....
Mobility and Vehicle Mechanics, 2018
Motor vehicle industry is nowadays exposed to numerous serious challenges, mostly related to its ... more 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.
Tehnicki vjesnik - Technical Gazette, 2016
Original scientific paper This paper focuses on the identification of failure causes of a bolted ... more Original scientific paper This paper focuses on the identification of failure causes of a bolted joint used for the bedding of a primary column of an aerial platform. The tests conducted to determine chemical composition and mechanical properties have confirmed the 12.9 grade of the bolts. Also, mechanical properties tests and metallographic examination did not indicate any hidden defects caused by heat treatment (e.g. decarburisation etc.). On the other hand, visual and metallographic examination of cross-section as well as electron microscope scanning confirmed fatigue fracture of the bolts. Therefore, further analyses were done to check the dimensioning and the installation of the bolts. The effects on stress states in the bolts are presented from the standpoint of rated operating regimes, stiffness of joined elements, lubrication conditions of thread surfaces and temperature incompatibility between the bolts and elements being joined. Pre-tightening torque value incompatible with lubrication conditions was found to be the main factor that led to high stress values that initiated and later intensified the fatigue process which ended in fatigue failure of the bolts.
Strojniški vestnik – Journal of Mechanical Engineering, 2011
Mobility and Vehicle Mechanics, 2018
Limited oil reserves and the ecological consequences of its use in motor vehicles impose an incre... more 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.