Trans Motauto World
Vol. 2 (2017), Issue 1

Table of Contents

  • TRANSPORT TECHNICS. INVESTIGATION OF ELEMENTS. RELIABILITY

    • OPTIMIZATION OF MAGNETIC FLUX IN ELECTROMAGNETIC VIBRATING GENERATORS

      pg(s) 3-4

      Recent development in manufacturing of rare-earth permanent magnets provides a large variety of their shapes and magnetic properties. Ring shaped permanent magnets, mainly FeNdB magnets with high magnetic flux density (1.5 T), are frequently used for the construction of electromagnetic vibrating power generators for example in battery electric vehicles. The key parameter for optimal construction is the efficiency of power conversion which characterizes how effectively vibrating power generator converts kinetic energy into electric energy and stores it in batteries. The presented contribution brings an overview of concepts which increase this efficiency: 1) magnetic structure of axial magnets with like-poles facing each other incorporating soft magnet spacers; 2) cylindrical Halbach array magnetic structure; 3) outer magnetic shield structure for the concentration of magnetic flux. In the experimental section is also introduced constructed prototype of electromagnetic vibrating power generator and measurements of induced voltages.

    • DIRECTIONS FOR LOAD AND SAFETY APPRECIATION OF CARRYING STRUCTURES COMPONENT ELEMENTS

      pg(s) 5-7

      This paper presents the directions for load and safety appreciation of carrying structures component elements and their application to a particular object respectively carrying structure of rotating excavator working wheel. Load and safety of the carrying structure and its component elements are estimated based on the calculation of load and safety factors. The estimated load is based on the calculated value of load factors, while the safety by comparison of the calculated safety factors to the values of recommended minimum safety factors obtained by examinations of such structures in practice. With these indicators we have a situation where we are providing the static strength control of the analyzed elements. The paper presents numerical values of the load and safety coefficients for the excavator SRs-630 working in the coalmine "Suvodol" Bitola, for all characteristic working regimes in its exploitation lifetime. The numerical values of load and safety coefficients relate to clamps of the working wheel carrying structure and the most loaded joint of this structure.

    • FUZZY PROPORTIONAL DERIVATIVE APPROACH FOR VIBRATION CONTROL OF VEHICLES

      pg(s) 8-10

      In this paper a fuzzy logic proportional derivative controller is proposed for suppressing vertical vibrations of vehicles. Initially quarter vehicle model is presented. Afterwards fuzzy proportional derivative approach is described in order to minimize vertical displacement of vehicle body. The proposed controller is applied to quarter vehicle model to demonstrate and evaluate performance of the controller. Time responses of vehicle body displacement, acceleration and suspension deflection are compared between controlled and uncontrolled cases. The proposed controller exhibits promising behavior.

    • VIBRATION CHARACTERISTICS OF QUARTER CAR SEMI-ACTIVE SUSPENSION MODEL – NUMERICAL SIMULATIONS AND INDOOR TESTING

      pg(s) 11-16

      This paper describes the results of numerical simulations and laboratory experiments of quarter car semi-active suspension model. Elastic characteristic of the coil spring and damping characteristics of the shock absorber in various operating modes are determinate. The amplitude-frequency characteristics and transfer function of the system with various damping coefficient are obtained. The results can be used to design semi-active suspension control strategy for improving ride comfort and road holding of ground vehicles.

  • TRANSPORT. SAFETY AND ECOLOGY. LOGISTICS AND MANAGEMENT

    • CALCULATION ALGORITHM FOR PEDESTRIAN GREEN TIME

      pg(s) 17-18

      Places of crossing the roadway by pedestrians, regulated by traffic lights, provided largely safe passage. In these cases attached times of individual signals have to guarantee minimum delay of both streams. The paper presents a calculation algorithm for pedestrian green time according to the intensity of traffic flows and pedestrian flows in certain road conditions.

    • THE NOISE FROM VEHICLES AND TRANSPORT FLOW

      pg(s) 19-20

      Increases in road traffic lead to the expansion of areas of the acoustic discomfort, and the noises from vehicles acquire social importance. The noise as a set of sounds is characterized qualitatively and quantitatively by two main indicators: the sound pressure or intensity level, which have different effect on the human body. In addition, in terms of the effect on the human body, the prefence is given to the noise equivavlent level. The study of the noise equivalent level can be carried out in two ways. The first one consists in fact that at a given moment of time, at any point in space, there are summarized the noise level or sound energy intensity from all radiation sources, but another way implies summarizing the selected sound energy sources during a certain time period. So, in order to determine the noise equivalent level of one vehicle during that time period, which is required for passing a certain section, it is necessary to know those laws, which characterize traffic conditions and the calculated changes of the noise level in these conditions.

    • ITS-RELATED ASPECTS OF DEVELOPMENT OF URBAN TRANSPORT SYSTEMS

      pg(s) 21-29

      This article provides an overview of an ITS-related application developed for Urban transport systems in Russia.

      In today’s society, where the public relies increasingly on the transport network, Russian Federation, as the many other countries, faces tough challenges ahead. From congestion, safety to environmental impact, technology provides a rich variety of options to address existing and future concerns, and Intelligent Transport Systems are at the forefront.

      Deregulation of public transport in Russian market places new challenges for national transport companies. There is an increasing need of new service models and operational schemes allowing improved transport offer and competitive advantages. Investments are necessary to optimize the use of transport resources and increase the quality of service for the customers.

      Information and communications technologies play a fundamental role to achieve these objectives. This is the case with both flexible transport, where telematics allows to optimize resources and improve mobility services for the customers, and with optimization of regular, line based transport services.

      Thereupon, coordinate (position data), time and the navigation support (CTNS) together with telecommunications became a main informational background for automation basic technologies for the Urban transport systems.

    • ANALYZING THE LEVEL OF HIGH TROPOSPHERC OZONE DURING THE SUMMER 2014 and 2015 IN SKOPJE, R.MACEDONIA

      pg(s) 30-32

      Ozone is health-hazardous air pollutant and his level in the living environment is very important to be tracked and understand. This specific gas in nowadays occurs as byproduct of certain human activities, especially with car pollution and naturally due to increased temperature. Therefore, it is important to understand the relationship between this variable. The focus of this paper is to model this relationship, with data collected for period of 3 months in 2014 and 2015(summer period). According to the models obtained with machine learning methods, high level concentrations of ozone was found if temperature of the air is higher than 30.15oC and concentrations of NO2 are lower than 16.93 mg/m3(in 2013). Encourage by this model, in this paper we go further and extend our research to include more data (from 2014 and 2015) and different methods to find other influencing factors that contributes to high concentration of ozone.

    • A STUDY ON THERMAL PERFORMANCE OF LED SIGNAL HEADS USING INFRARED THERMOGRAPHY

      pg(s) 33-36

      This article presents results from a study on thermal performance of several LED traffic light heads. Thermal performance of an electronic equipment, especially LED luminaire, is a lifetime determining criteria. In order to simulate real life worst case scenario signal heads are placed in thermal chamber and the internal temperature is set to 60oC. A controller is made to control the LED signal heads with longest time sequences according to statutory requirements. Constant light mode is studied also. Measurements are made with infrared camera and thermocouple for verification. The measured solder point temperatures are used to calculate junction temperatures and estimate dangerous operating conditions.

    • RISKS AND SAFETY ISSUES RELATED TO USE OF ELECTRIC AND HYBRID VEHICLES

      pg(s) 37-40

      Nowadays hybrid vehicles take increasing share of new road vehicles, but also the electric vehicles have continuous development which is a sign of a serious beginning of new era of their use. The goals of introducing of these vehicles include lowering of the negative impact on the environment and also reducing of their operational costs. Together with the mentioned trends, there are some specifics related to the risks of using this type of vehicles. This paper gives the key elements related to the development of hybrid and electric vehicles with emphasis of the general distinctions in terms of conventional vehicles with internal combustion engines. The paper has focus on risk identification and hazards that can arise from hybrid and electric vehicles, which are specifically related to their technical differences from conventional vehicles with internal combustion engine. Those risks exist when the vehicles are in use, but also even when the vehicle is not in operation. There is also identification of potential risks for the emergency staff when there is accident with these types of vehicles. The paper also addresses the possible harmful events that can happen later or because of improper repairs of the vehicles. Having in mind that the literature sources are quite moderate and in Republic of Macedonia there is none, the conclusion represent an effort to systemize the available knowledge in order to help vehicle users and professionals to mitigate or lower the recognized risks.

  • VEHICLE ENGINES. APPLICATION OF FUELS TYPES. EFFICIENCY

    • SURFACE PLASMON RESONANCE – A PROMISING METHOD FOR ESTIMATING THE QUALITY OF MOTOR OIL

      pg(s) 41-44

      Shown in this paper is the possibility to diagnose quality of motor oil by using the method of surface plasmon resonance (SPR) Investigated in this work were four samples of the motor oil Genuine 5w-30 dexos 2, namely: the fresh one and three ones taken after car mileages 180, 430 and 712 km. When measuring the kinetics of refraction indexes for the studied samples of used oil, the authors observed a characteristic “shoulder” caused by sedimentation of oxidation and wear particles on the surface of SPR device sensitive element, while in the case of fresh oil there took place only the temperature drift of the refraction index. It has been experimentally shown that using the SPR method improves more than one order (from Δfmin = 0.17 vol.% down to Δfmin = 0.0107 vol.%) the detection limit and enhances sensitivity of measuring the wear particles concentration in motor oil as compared with the refractometric method. Thus, it is experimentally proved that the SPR method can be offered to control quality of motor oils as well as the degree of wear inherent to interacting parts of machinery.