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EN
An essential part of a sustainable city is sustainable transport; however, the development of transport has led to the growing noise pollution. It is obvious that the road-traffic noise has negative health impacts on the population in the cities. These effects should be reduced to ensure the sustainability of modern cities. The main purpose of the study was to compare the changes in the noise level in the mountainous city in 2012 and 2016 compared to 1990. A hypothesis was introduced that over the past 26 years, the level and severity of noise during the day and night increased along with traffic and the number of cars. In addition, a comparison of the value of the traffic intensity of passenger cars and trucks during the daytime in the years 2012–2016 was made. Additionally, the noise generated by vehicles during the day and night was compared. On the basis of the results obtained, it can be concluded that the level of noise during the daytime over the last 26 years has clearly decreased. The main factors that reduced the noise level were the improvement of the quality of vehicle fleet, directing transit traffic to the city beltways, as well as the local use of noise barriers. However, the level of noise intensity at night increased significantly. This is due to the increase in the total number of vehicles in the city and their high speed at this time.
EN
The aim of this paper is to estimate the mass concentrations of volatile organic compounds (VOCs) such as benzene (B), toluene (T), ethylbenzene (E) and m-, p-, o-xylenes (X) inside of the driver-compartment of motor vehicles. The results were compared with the Czech limits for indoor environments and the external concentrations. The experiments were carried out on various routes with different methods of ventilation. The volatile emissions detected inside the vehicle were investigated in the city of Brno, Czech Republic. Cabin air was collected using desorption tubes and the samples were analysed by thermal desorption gas chromatography with a flame ionisation detector coupled with a mass detector. VOC concentrations detected in the cabin of the vehicle ranged from 2.93 µg.m-3 to 7.96 µg.m-3 for benzene, 1.42 µg.m-3 to 4.38 µg.m-3. for toluene, 44.06 µg.m-3 to 152.00 µg.m-3 for ethylbenzene and 63.07 µg.m-3 to 479.62 µg.m-3 for xylenes. The indoor limit value for benzene, according to the Czech standard, is 7 µg.m-3. Levels of toluene were consistently below the Czech hourly standard, whose value according to the Czech standard is 300 µg.m-3. According to our findings, various methods of ventilation are an important factor influencing the BTEX pollution levels within the interior of the vehicle. In addition, this paper presents the influence results of benzene on the health of passengers inside the cabin of the vehicle. The results show that all age categories, especially children under the age of two, are exposed to increased health risks.
3
Content available Wheeled armored personnel carrier Ryś and Irbis
EN
The article presents the characteristics of the Ryś and Irbis wheeled armored personnel carriers (Polish abbrev. KTO) designed in Poland. They constituted a deep modernization of the Czechoslovakian SKOT medium wheeled armored transporter. The paper presents the genesis of works on these vehicles and their main contractor, Military Automotive Works No. 5 in Poznań, which has dealt with repairs and modernization of combat vehicles since the 1950s. In the following part, the tactical and technical data of the basic version of the Ryś wheeled armored personnel carriers and special-purpose vehicles based on it are discussed, with particular attention paid to the versions that are of interest to the Ministry of National Defense. Next, the Irbis wheeled armored vehicle, and the special-purpose versions built on its chassis are characterized and presented to the International Defense Industry Exhibition in Kielce.
PL
W artykule zaprezentowana została charakterystyka opracowanych w Polsce transporterów opancerzonych Ryś i Irbis, które stanowiły głęboką modernizację konstrukcji czechosłowackiego transportera opancerzonego SKOT. Przedstawiono genezę prac nad tymi pojazdami oraz ich głównego wykonawcę Wojskowe Zakłady Motoryzacyjne nr 5 w Poznaniu, które zajmowały się remontami i modernizacją wozów bojowych już od lat pięćdziesiątych XX wieku. W dalszej części omówiono dane taktyczno-techniczne wersji podstawowej transportera opancerzonego Ryś oraz wozów specjalistycznych na jego bazie, ze szczególnym zwróceniem uwagi na wersje będące obiektem zainteresowania resortu Obrony Narodowej. Następnie scharakteryzowano transporter opancerzony Irbis i zbudowane na jego podwoziu odmiany specjalne, które zaprezentowano ma Międzynarodowym Salonie Przemysłu Obronnego w Kielcach.
PL
Obecnie trudno sobie wyobrazić inżyniera mechanika bez znajomości metod numerycznych (CAE). Powszechne korzystanie z komputerów i rozwój metod numerycznych przyczyniły się do zwiększenia jakości projektów inżynierskich. W artykule przedstawiono rozwój metod numerycznych i ich praktyczne zastosowania w budowie maszyn i pojazdów. Precyzja obliczeń oraz możliwość realizacji w rzeczywistości wirtualnej złożonych symulacji zwiększyła niezawodność produkowanych maszyn i pojazdów z jednoczesnym obniżeniem kosztów.
EN
Nowadays, is difficult to image mechanical engineer without skills of computer aided engineering (CAE) methods. Common use of computers, PC popularity and numerical methods development have been the reason of rapid growth of engineering design quality. Development of numerical methods and their practical applications in machine and vehicle building were presented. Precision of calculations as well as possibility of realization in virtual reality complex simulations increased reliability of produced machines and vehicles with simultaneous cost decreasing.
EN
This paper concerns the impact of coil factors on a hydraulic electric inerter-based vehicle suspension. A hydraulic electric inerter device is first introduced, and the dynamic model of a quarter car is established. Subsequently, the influences of the coil factors on the body acceleration, suspension working space and dynamic tire load are investigated in both the time and frequency domain. Results show that the coil factors have a slight effect on the vehicle suspension performance, decreasing the root-mean-square (RMS) of the vehicle body acceleration and increasing the RMS of the suspension working space and dynamic tire load.
6
Content available remote Ecological and functional aspects of operation of electric vehicles with fuel cell
EN
Hydrogen can have great importance in seven areas of necessary changes in the transformation of the power system, including transport (especially motor transport), industrial processes, thermal and energy production in the construction industry and production processes. Hydrogen fuel cell electric vehicles (FCEVs) do not cause local air pollution because they have zero “tailpipe” emissions. Essential are ecological and functional aspects of operating vehicles equipped with fuel cells. However, noteworthy is also the development of the refilling infrastructure. The functionality of FCEVs to a considerable degree depends on the functionality of fuel cells.
PL
Wodór może mieć ogromne znaczenie w siedmiu obszarach niezbędnych zmian transformacji systemu elektroenergetycznego, w tym w transporcie (zwłaszcza w transporcie samochodowym), procesach przemysłowych, produkcji ciepła i energii w budownictwie oraz procesach produkcyjnych. Elektryczne pojazdy wodorowe z ogniwami paliwowymi (FCEV) nie powodują lokalnie zanieczyszczenia powietrza, ponieważ mają zerową emisję z „wydechu”. Istotnymi są ekologiczne i funkcjonalne aspekty eksploatacji pojazdów wyposażonych w ogniwa paliwowe. Jednak istotnym jest także rozwój infrastruktury ich tankowania. Funkcjonalność pojazdów (FCEV) w istotnym stopniu zależy od funkcjonalności ogniw paliwowych.
EN
The article deals with a FEM analysis of main parts of an engineering design of a pneumatically controlled manipulator, which will serve for mounting a compressor to a PO536 car chassis. This car chassis belongs to SUV cars and it is equipped with a pneumatic suspension system. It is the chassis of a Porsche Cayenne car produced in the Slovak Republic. The designed manipulator will be located on the assembly line of this vehicle. Except of FEM analyses of designed important parts of the manipulator, which are necessary for verification of safety of the design in order to obtain distribution of stresses and deformations in a structure, the it contains also the design of a pneumatic circuit of the manipulator together with pneumatic logic and it individual components. Based on three-dimensional model, there will be possible to generate drawings of the manipulator for manufacturing of the device and its application to the real operation.
EN
Development of active safety systems of automobiles is nowadays based not only on road tests, but also on computer simulation of vehicle's curvilinear motion. To properly perform simulation, all required model parameters have to be properly estimated. The less complicated model is, the less parameters it requires. So that, it makes no sense to apply too complicated models, if we are not able to estimate parameters with relatively low error. One of the most popular is two- degree-of-freedom flat model to describe curvilinear motion of automobile. It is widely used in design and improvement of active safety systems. The article discusses the application of simple two- degree-of-freedom flat model of automobile, which requires only several parameters. These parameters are: mass of a vehicle, location of center of gravity of a vehicle, yaw mass moment of inertia of a vehicle, side-slip characteristics. Furthermore, to be able to compare simulation and measurement results, it is necessary to know some input signals such as steering wheel angle and velocity of a vehicle, recorded during road tests. In this article signal of steering wheel angle was taken from Controller Area Network (CAN) bus. In case of model of a vehicle, the Authors decided to compare the results of simulation using two different side slip characteristics known as the dependence between lateral reaction force and side slip angle: linear characteristic (constant cornering stiffness) and the characteristic represented by Pacejka’s Magic Formula in steady-state version.
EN
This paper presents the investigations of vibrations of a vehicle equipped with controlled magneto-rheological (MR) dampers and aerodynamic elements. A scaled sports vehicle model was developed to conduct this research. The tests were carried out with kinematic excitation resulting from road roughness and motion at a variable speed. During the airflow, the aerodynamic elements forces and moments on the test body. Vehicle vibrations are limited by the means of MR controlled dampers. The damping force is determined on the basis of an algorithm, where various strategies for determining forces in MR damper have been adopted. Two criteria were considered for assessing the effectiveness of the control algorithm - minimising vertical acceleration and changes in wheel normal reactions on road surface. This paper presents the results of those studies.
PL
W niniejszym opracowaniu zaprezentowany został mechatroniczny system służący do redukcji drgań pojazdów. Przedstawione zostały właściwości materiałów „inteligentnych", których cechy można zmieniać w stosunkowo krótkim czasie. Pozwala to na wykorzystanie takich materiałów do budowy sterowanych tłumików drgań, które mogą działać niemal w czasie rzeczywistym. Zaprezentowane zostały oryginalne konstrukcje tłumików magnetoreologicznych oraz tłumików z zaworem piezoelektrycznym. W pracy przedstawione zostały wyniki badań właściwości półaktywnych tłumików, na podstawie których został przyjęty model sterowanego tłumika oraz opracowana została metodyka identyfikacji jego parametrów. Przedstawiony został półaktywny system redukcji drgań pojazdu, gdzie wykorzystano cztery sterowane tłumiki. Powstające w tych tłumikach siły tarcia mają istotny wpływ na intensywność drgań pojazdu. Do oceny skuteczności sterowania siłami tłumienia w zawieszeniu pojazdu przyjęto funkcjonał kryterialny, który zależy od tych sił. Należy podkreślić, że siły tarcia w tłumikach wyznaczane są w każdej chwili. Pozwala to na wyznaczenie sygnałów sterujących działaniem półaktywnych tłumików. Przyjęty algorytm wyznaczania sił tarcia został wykorzystany podczas badań symulacyjnych drgań pojazdu z półaktywnymi tłumikami. Przeprowadzone zostały również badania terenowe pojazdów ze sterowanymi tłumikami. Na podstawie analizy wyników badań stwierdzono, że półaktywne systemy wpływają na zmniejszenie intensywności drgań pojazdów.
EN
This study discusses the mechatronic system for reduction of vehicle vibration. Properties of "intelligent" materials have been presented, whose features can be changed in relatively short time. It allows for using such materials to build the controlled vibration dampers which can operate nearly at real time. The original designs of magneto-rheological dampers as well as dampers with the piezoelectric valve have been presented. This work demonstrates results of the research regarding the properties of semi-active dampers. On this basis, a model for the controlled damper has been adopted, and the methodology of the identification of its parameters has been developed. A semi-active system for reduction of vehicle vibration has been presented, in which four controlled dampers were used. The friction forces generated in these dampers significantly influence the intensity of the vehicle vibration. To evaluate the effectiveness of control of damping forces in the vehicle suspension, the criteria functional has been adopted, which depends on these forces. It should be emphasised, that friction forces in the dampers are determined at every moment of time. It allows for determination of signals controlling the operation of the semi-active dampers. The adopted algorithm for determination of the friction forces was used during tests of the simulated vibration in a vehicle with semi-active dampers. Also, off-road tests of the vehicles with controlled dampers were carried out. Analysis of the test results enabled the conclusion that the applying of semi-active systems decreases the intensity of vehicle vibration.
11
Content available remote Fuel and electric energy consumption measurement of vehicles
EN
The article presents methods for measuring fuel consumption and electricity used in tests of rolling stock, buses, trolleybuses and trams. Based on the results of the performed experiments, the limitations of currently used research methods have been described and possible solutions have been proposed.
PL
W artykule przedstawiono metody pomiaru zużycia paliwa i energii elektrycznej stosowane w badaniach taboru kolejowego, autobusów, trolejbusów oraz tramwajów. Na podstawie zebranych doświadczeń opisano ograniczenia stosowanych obecnie metod badawczych i wskazano możliwe rozwiązania.
12
Content available remote Environmentally friendly fuel usage: Economic margin of feasibility
EN
In the world there are two main problems concerning energy and ecology. Despite the crude oil price fluctuation, it has tended to increase. Moreover fossil fuel burning emits hazard compounds, including greenhouse gas. To solve them alternative fuels for vehicle have to be used. In due to properties, their usage impacts on the engine efficiency. The alternative fuel usage needs additional investment costs on the vehicle engines adaptation and fuel supply infrastructure. So, decisions must be based on mathematical apparatus. Three submodels were used in the suggested mathematical model: energy and economic indicator for fuels; energy and economic indicator for vehicles; criteria for investment projects. As a criterion of investment projects the profitability index has been grounded. The mathematical model and the algorithm for determining the feasibility of the alternative fuel utilization have been developed. The proposed algorithm includes the following stages: calculation of the fuel energy cost; calculation of the criteria for vehicles; determining the maximum value of investments; making decisions. Biofuels and gaseous fuels for some countries have been studied. The economic attractiveness of the alternative transport fuels has been presented. According to mathematical modeling, gaseous fuels are more economically attractive compared with liquid biofuels. Among gaseous fuels, LPG has a higher economic efficiency. The economic margin of alternative fuel application feasibility has been determined.
EN
In this paper, a new three-dimensional vehicle with tandem axels at the rear is developed to determine dynamic response of bridge deck under load applying truck. The vehicle is modeled by a three-axle dynamic system with 9 degrees of freedom to accurately simulate the disposition and the intensity of loads on the bridge deck. The bridge deck is modeled by a thin, orthotropic, multi-span plate. The road surface irregularities are modeled by a random function characterized by a spectral roughness coefficient and power spectral density. The modal method is used to solve the equation of motion of the bridge deck. Equations of motion of the vehicle are obtained using the virtual work principle. The coupled equations of motion vehicle/bridge deck are integrated numerically by Newmark’s method. A computational algorithm in FORTRAN is then elaborated to solve the integrated equations of motion in a decoupled, iterative process. A numerical example of an orthotropic, three-span bridge deck, excited by a 9 degree of freedom truck is presented. The resulting distribution of the Dynamic Amplification Factor (DAF) on the bridge deck does not reflect any particular trend, because high values can be obtained at points where the vertical displacement is small. The DAF is significant only under the interaction force. Thus, the road surface roughness was shown to have a significant influence on the dynamic vehicle/bridge deck interaction forces.
EN
This paper presents a study of vibrations appearing in a vehicle in the process of its operation. The authors describe the primary source of the vibrations and their propagation in the entire structure. The observations were performed on the passenger cars with various gasoline and diesel engines. The aim was to examine the level of damping factor in the different locations in the car, precisely specified for the purpose of this studies. The secondary goal was to develop an effective method of obtaining and analyzing signals generated during the engine operation. The chosen instrument was Laser Doppler Vibrometer (LDV), which is used as the non-intrusive measurement utensil to detect velocity variations in designated places. The signals are gathered and collected as group of sinusoidal characteristics in the time domain. In order to achieve specific information about every component of the original signal, the authors apply Fast Fourier Transform (FFT) as the analyzing method. It allows to distinct the basic sinusoidal characteristics in the frequency domain through the spectral analysis. Based on the results, the authors are able to distinguish the dominant modes from the complex signal and indicate their impact on the car.
EN
Presentation of the number of passenger cars, vehicles other than passenger cars with GVM up to 3.5 tons and above 3.5 tons (trucks, buses and special vehicles), registered in Poland as at the end of 2015, with types of energy carriers. Forecasts of transport performance of the vehicle fleet and the forecast of the fleet volume in Poland by year 2035. Expert forecasts of energy carriers consumption (petrol, diesel oil, LPG, CNG, electric power, hydrogen) up to year 2035.
EN
In the regulations concerning approval of light vehicles starting from September 2019 it will be necessary to conduct exhaust emissions tests both on a chassis dynamometer and for real driving emissions. It is a legislative requirement set forth in EU regulations for the purpose of the RDE (Real Driving Emissions) procedure. To decide on the RDE route for the purpose of the LV exhaust emissions tests many requirements must be fulfilled, regarding for example external temperature and the topographic height of the tests, driving style (driving dynamic parameters), trip duration, length of respective test sections (urban, rural, motorway, etc.). The works on outlining RDE routes are continued across the country in various research centres. Specifying the RDE route for test purposes, i.e. works in which the authors of this article are actively involved, has become a major challenge for future approval surveys concerning the assessment of hazardous emissions from light vehicles and for development studies focusing on - for example - the consumption of energy in electric and hybrid vehicles. The test route has been chosen to ensure that the test is performed on a continual basis. Data were recorded on a constant basis with the minimum duration of the test achieved. The test involved light vehicles and PEMS device for measuring the exhaust emissions, vehicle’s speed, completed route, etc. The device was installed in such manner as to ensure that its impact on the exhaust emissions from the tested vehicle and on the device’s operation is the least. The vehicle load was consistent with the requirements of the standard and included the aforesaid measurement device, the driver and the operator of PEMS. The tests were carried out on working days. The streets and roads used for the tests were hard-surfaced. Measurements were performed in accordance with the requirements of RDE packages (Package 1-4), i.e. taking into account - among others - the engine cold start. The article discusses the method of outlining the test route fulfilling the specific requirements for RDE testing. Chosen results of exhaust emissions from a passenger car with a spark-ignition engine along the defined RDE test route have been provided. The tests discussed in the article are introductory in the area of RDE tests and provide an introduction into further studies of exhaust emissions and energy consumption in real driving conditions in conventional vehicles and vehicles with alternative engines, e.g. hybrid and electric vehicles.
PL
W artykule zaprezentowana została metoda diagnostyki bezpośredniej termorezystancyjnych czujników temperatury stosowanych w pojazdach mechanicznych. Przedstawione zostały charakterystyki R=f(T) oraz ich parametry techniczne i eksploatacyjne. Omówiono typy czujników powszechnie stosowanych układach pomiarowo-rejestrujących oraz funkcje, które spełniają w systemach sterujących w pojazdach. Na przykładzie wybranych typów czujników przedstawiona została prosta i szybka metoda diagnostyki bezpośredniej ich stanu technicznego. Przedstawione zostało stanowisko diagnostyczne oraz wyniki badań i wnioski dotyczące badanych czujników.
EN
The article discusses thermistor temperature sensors used in automotive vehicles. The characteristic types R=f(T) of thermoresistors as well as their technical and operational parameters are presented. The applications of particular types of thermoresistors in temperature measurements in automotive vehicles are discussed. On the example of the coolant temperature sensors diagnostics is presented. The test results and conclusion regarding the tested sensor diagnostics is presented. The test result and conclusions regarding the tested sensors are presented.
EN
Vehicle Routing Problem (VRP) is the process of selection of the most favorable roads in a road network vehicle should move during the customer service, so as such, it is a generalization of problems of a commercial traveler. Most of the algorithms for successful solution of VRP problems are consisted of several controll parameters and constants, so this paper presents the data-driven prediction model for adjustment of the parameters based on historical data, especially for practical VRP problems with realistic constraints. The approach is consisted of four prediction models and decision making systems for comparing acquired results each of the used models.
EN
Equipment set for studying dynamics characteristics of vehicles as automatic control objects is presented. Dynamics characteristics of various mobile objects were studied at test site. Experimental procedure, electronic data processing using a method of adjustable equivalent model is provided. Research data and received mathematical models are provided.
PL
Przedstawiono sprzęt przeznaczony do badania dynamicznych cech pojazdów jako obiektów kontrolowanych automatycznie.
20
Content available remote Influence of steering method on efficiency of pneumatic-hydraulic drive
EN
This article presents impact of control strategies for efficiency of pneumatic-hydraulic drive. The article is continuation of previous article where impact of control algorithm for characteristics of pneumatic-hydraulic drive is presented.
PL
Artykuł przedstawia wyniki eksperymentu prezentującego wpływ metody sterowania na sprawność pneumatyczno-hydraulicznej jednostki napędowej. Artykuł jest kontynuacją wcześniejszych prac, gdzie prezentowano wpływ algorytmu sterującego na charakterystyki pneumatyczno-hydraulicznej jednostki napędowej.
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