Keresés

Keresési eredmények

• Survey of the Application Fields and Modeling Methods of Automotive Vehicle Dynamics Models

  196-209

  Szántó András

  Hajdu Sándor

  Deák Krisztián

  Megtekintések száma:

  201

  In this paper, a review is presented on automotive vehicle dynamics modeling. Applied vehicle dynamics models from various application fields are analyzed and classified in the first section. Vehicle dynamics models may be simplified because of different reasons: several control/estimation/analysis methods are suitable only for simplified models (e.g. using control-oriented models), or because of the computational cost. Detailed/truth models of vehicle dynamics represent another field of vehicle dynamics modeling, these models play an important role in the virtual prototyping of vehicles. In the second section, the main modeling considerations of vehicle dynamics are presented in longitudinal, lateral and vertical directions. Various physical effects must be considered in the case of vehicle dynamics modeling, a lot of these effects are significant only in a specific direction of the vehicle body, which is the main potential of model simplification. The section presents vehicle modeling considerations in all of the three translational directions of the vehicle body.

• Using the Photostress Method to Determine the Residual Stresses

  24-38

  Alzyod Hussein

  Ficzere Peter

  Megtekintések száma:

  152

  Strains and stresses in loaded and photoelastically coated structural members can be determined using the PhotoStress method. The quantitative values of variations in the principal strains (stresses) and their directions could be employed to get the strain or stress components field on the entire coated surface. In the PhotoStress experiment, isochromatic fringes give qualitative and quantitative information. It provides a source of information on the directions and magnitudes of principal strain and principal normal stress on the surface of photoelastic coated parts. This article reviews the principle of using PhotoStress analysis to measure the residual stress and provides the boundary condition of using this method.

• Maintenance of Electric and Hybrid Vehicles

  37-46

  De Souza Araujo Paulo Victor

  Komlósi István

  Varga Tamás Zoltán

  Menyhárt József

  Megtekintések száma:

  475

  An electric car is a vehicle powered by one or more electric engines, utilizing energy stored within batteries that are rechargeable. The first register of a usable electrical vehicle dates from 1880s. A hybrid vehicle incorporates two or more different power types, including, e.g., gasoline engines and electric motor. The goal in this work is to present the overall overview of the structure of the electric, hybrid and electric-hybrid vehicles, advantages and disadvantages of these types, the main points to focus when maintaining these and the challenges involved in its production and maintenance.

• Vehicle Modelling and Simulation in Simulink

  260-265

  Szántó András

  Hajdu Sándor

  Megtekintések száma:

  390

  In this paper a vehicle dynamics model is presented, which is an example that contains all the necessary aspects of making a decent vehicle model. Several examples show the use of such a model: basic vehicle dynamics phenomena can be recognized with the simulation of a detailed vehicle model. We are dealing with the connection between downforce and under/oversteer in this paper. In addition, the use of numerical simulations in the field of control systems is pointed out by an example of simulating an ABS control for the vehicle.

• Improving Safety & Ride Comfort through Dual Suspension System in Road Vehicles

  30-36

  Kumar Chandar

  Arain Zahid Ali

  Raza Syed Ahmed

  Kumar Suresh

  ul Abedin Abidi Syed Zain

  Lal Chaman

  Megtekintések száma:

  167

  The essential objective of the proposed suspension framework is to limit the undesired disturbance of a vehicle because of uneven surfaces on streets. This framework in vehicles is comprise of some fundamental components like dampers and springs which ingests the stuns that are instigated by unusual streets. In any case, these frameworks can just work up to a predefined constrain. Vehicle suspension frameworks are planned by taking the solace capacity of a traveler in record and to enhance the street grasp on each surface.

  This examination proposes an idea for structuring a superior suspension arrangement of vehicles to upgrade the nature of the drive without corrupting the dependability of the vehicle plan. In this exploration, a mix of two suspension framework is presented in which one goes about as an essential suspension while different fills in as an optional framework that can adequately lessen the vibrations. This mix upgrades the customary framework that is right now introduced in vehicles without bargaining on solace and street hold.

• Személygépjárművek dinamikai modellezési eljárásainak áttekintése

  723-727

  Deák Krisztián

  Hajdu Sándor

  Szántó András

  Megtekintések száma:

  208

  A járműdinamikai modellek a modell egyszerűsítése alapján két csoportra oszthatók. Vannak egyszerűsített modellek, amelyek során elhanyagolásokkal élünk: ezek jellemzően a hossz-, oldal- és függőleges irányok közül nem tartalmazzák az összes irányt. Az egyszerűsített modellekre több ok miatt is szükség lehet: vannak szabályozási, becslési, valamint analízis módszerek, amelyek csak egyszerűsített modellek alapján alkalmazhatók, valamint a számítási idő miatt is szükség lehet egyszerűsítésre. Az egyszerűsített modellek mellett léteznek valós modellek, amelyek célja egy virtuális plant biztosítása a valós járműről, virtual prototyping alapú fejlesztésekhez. Ebben a cikkben egy rövid bevezetés után néhány egyszerűsített járműmodell kerül bemutatásra.

• Introduction to Design and Analysis of Torsional Vibration Dampers in Vehicle Industry

  310-324

  Venczel Márk

  Veress Árpád

  Megtekintések száma:

  318

  The crankshaft of today’s internal combustion engines with high performance output are exposed to harmful torsional oscillations originated from the unbalanced gas and inertial forces. To avoid the fatigue damage of engine components, caused by the undesired vibrations, torsional vibration dampers can be applied. Viscodampers are one type of the torsional vibration dampers, which operational fluid is silicone oil. For cost-effective R&D activities and production, finite element and finite volume numerical discretization methods based calculation techniques must be involved into the engineering work supported by the modern computer technology. The aim of this paper is to provide an insight into the multidisciplinary design and development process of visco-dampers in vehicle industry applications. Four different examples as structural, fatigue, CFD analyses and structural optimization have been introduced in the present work. It turned out from the static structural and fatigue analyses, that the investigated damper has safety factor over the limit for both static structural and fatigue analyses, so it is suitable for the given load conditions. In the structural optimization process 34.36% mass reduction has been achieved. According to the coupled fluid dynamic and heat transfer simulations a rather stagnating air zone evolved between the engine and the damper during the operation, which can cause efficiency reduction of cooling fins mounted onto the housing. In light of the numerical results, the suitable damper position has been determined for the highest heat transfer.

• Dinamikus tesztek soros gerjesztésű DC motoron. A motorral hajtott jármű fékezésének szimulációja

  15-20

  Szántó Attila

  Szíki Gusztáv Áron

  Sarvajcz Kornél

  Megtekintések száma:

  86

  A következőkben bemutatjuk a járműdinamikai szimuláció szerepét és hozzájárulását a Debreceni Egyetem Műszaki Karán folytatott járműfejlesztésekhez. Ismertetjük a szimulációs program részét képező soros gerjesztésű egyenáramú motor szimulációjához szükséges bemenő műszaki paramétereket, azok meghatározásához kifejlesztett eljárást, valamint a motoron végzett dinamikus tesztméréseket, és azok eredményét. Továbbá bemutatjuk a motor által hajtott járműhöz kifejlesztett szimulációs program legújabb – a fékezés szimulációjával kibővített – változatát, valamint a program futtatásával kapott eredményeket.

• Examining the Movement Differences in the Behavior of Normal and Rack Railway Vehicle

  96-103

  Nagy Andor

  Lakatos István

  Megtekintések száma:

  259

  The rack railway is a special type of railroad. There weren”t much built worldwide, and their number is decreasing. Now, in Budapest, there is a possibility to create an interoperable vehicle, based upon the experience gained from the previously operated line, and all the research regarding its unique characteristics. One from the many important sector of its operation, is the rail/rack/vehicle system. Its mechanical model is far more complex than a traditional railroad vehicle. We will demonstrate its behaviorial differences from a traditional railroad vehicle.

• Utilization of 3D Printing in Replacement of Basic Plastic Workpieces

  274-282

  Kristály Álmos

  Ficzere Péter

  Megtekintések száma:

  195

  In the experiment, a 3D printed cogwheel is made using the FDM technology to replace a broken part in a sewing machine. The aim of the project is to examine if a 3D model can be created and manufactured using only entry-level technical knowledge and tools. By the end of the article, it will be apparent that creating functioning plastic parts with a hobby 3D printer and basic CAD experience is very much possible.

• Járművek menetdinamikai szimulációja Matlab/Simulink környezetben

  36-41

  Szántó András

  Hajdu Sándor

  Megtekintések száma:

  244

  A következőkben járművek menetdinamikai szimulációjának a lehetőségeivel foglalkozunk. Az egyszerű kétkerék-modelltől kezdve, a valós futóművel rendelkező jármű tetszőleges útfelület mentén történő mozgásának a szimulációját mutatjuk be. A MATLAB, Simulink, valamint a Simscape nagyon jól használható eszközöket biztosít az előbb említett célok eléréséhez. Az így kapott járműmodell gyakorlati felhasználásának a hasznába is betekintést nyerünk, hiszen a szimuláció során ismert adatok birtokában gyakorlatilag bármilyen szabályozó algoritmus szimulációjára lehetőségünk van: a cikkben egy egyszerű ABS szabályozás kerül bemutatásra.

• Aktív hűtés hatásainak vizsgálata 3D nyomtatás esetén

  39-47

  Ficzere Péter

  Megtekintések száma:

  131

  A 3D nyomtatás egyre szélesebb körben alkalmazott gyártási eljárás. A gépek és anyagok fejlődésével egyre több ember számára hozzáférhető ez a technológia, egyre egyszerűsödik az alkalmazása. Mindemellett a technológia sajátosságaiból adódóan azért igényel gyártástechnológiai ismereteket. Bizonyos esetekben nagy túllógások esetén szükséges a frissen lerakott rétegek mielőbbi megszilárdítása. Ezt aktív hűtéssel lehet megvalósítani, ami viszont hatással lehet a darab anyagtulajdonságaira is. A kutatás a gyártás során alkalmazott aktív hűtés hatásait vizsgálja

• Vehicle Dynamic Simulation Possibilities Using AVL Cruise M

  309-323

  Nemes Dániel

  Pálfi Tibor

  Hajdu Sándor

  Megtekintések száma:

  194

  In most cases, when creating vehicle dynamics simulations, we need software that can speed up model creation and simulation. There are many programs on the market for this purpose, but they have different knowledge and user interfaces. We present in this article briefly introduces the use of one of the market's leading vehicle simulation software, the AVL Cruise M.

• Artificial Intelligence Possibilities in Vehicle Industry

  148-154

  Menyhárt József

  Megtekintések száma:

  257

  There have been several attempts during the last decades to extend the ranges of application of artificial intelligence. The aim of the development for AI is to replace human intelligence and experience. The ultimate aim for machines and vehicles is to run much more efficiently and with higher reliability than ever before. The Artificial Techniques (AI) used a wide range of expert systems to optimize problems. Hybrid intelligent management systems have become increasingly influential in artificial intelligence during the last decades. As a result, maintenance and fleet management systems have undergone significant development. By choosing adequate maintenance or operating strategy and taking user behaviour into consideration, these systems can not only increase the reliability and efficiency of vehicles but can also result in financial savings. The paper tries to discusses the applications of AI techniques in predictive maintenance and vehicle industry.

• Elektromos hajtású tanszéki versenyautó járműdinamikai modellezése

  106-114

  Attila Attila

  Szíki Gusztáv Áron

  Hajdu Sándor

  Megtekintések száma:

  121

  A következőkben egy MATLAB környezetben kifejlesztett járműdinamikai szimulációs programot ismertetünk. A program a műszaki adatokból, mint bemenő paraméterekből, előállítja a jármű menetdinamikai függvényeit, és közvetve alkalmas a műszaki paraméterek optimalizálására. A programot a DE MK Gépészmérnöki Tanszékén tervezett és kivitelezett elektromos meghajtású versenyautóra már sikeresen alkalmaztuk.

• Járművek menetdinamikai szimulációs lehetőségei AVL Cruise M környezetben

  743-748

  Nemes Dániel

  Pálfi Tibor

  Hajdu Sándor

  Megtekintések száma:

  231

  A járműdinamikai szimulációk készítésekor a legtöbb esetben szükségünk van egy szoftverre, amellyel meggyorsíthatjuk a modell készítését és szimulációját. Erre a célra számos program van a piacon, azonban ezek eltérő tudással és felhasználói felülettel rendelkeznek. Cikkünkben röviden bemutatjuk a piac egyik vezető járműszimulációs szoftverének használatát, az AVL Cruise M-et.

• Improvement of High Strength Automotive Steels Wettability Properties Using CO2 Laser Surface Treatment

  422-427

  Tajti Ferenc

  Berczeli Miklós

  Weltsch Zoltán

  Megtekintések száma:

  156

  As a result of stricter environmental and safety standards, vehicle manufacturers have to reduce the weight of the vehicles, because 10% weight loss cause 8-10% reduction of fuel consumption. To reduce car’s weight and increase safety, vehicle manufacturers use high-strength steels. Further weight reduction can be achieved by using corresponding bonding technology (soldering, sticking) and optimizing these technologies can increase the strength of the joints. According to literature research, the improvement of interface properties has a large effect on bonding technologies. In order to improve interface properties, we can use multiple surface treatments. In our research we investigate the effects of CO2 laser surface treatment on high strength steels, because CO2 lasers are often used in the vehicle industry. In order to detect the effect of surface treatment, we investigate the wettability of the treated and untreated steels. In our research we measure the surface tension of treated and untreated steels. Our main goal is to improve wettability properties thus the bonding technology. In our research we used DP 600 high strength steel sheet with the thickness of 1 mm. We cut the steel sheet to 25mm wide and 55mm long workpieces. Before the surface treatment, the workpieces had to be cleaned and degreased using methanol. We searched for parameters that do not cause any visible changes on the surfaces. Among the parameters of the treatment we were able to change the output power of the laser. We used contact angle measurement to examine the wettability.

• Literature Overall of Fatigue Analysis Approaches of Vehicle Components Made of Rubber

  130-140

  Tomposné Szüle Veronika

  Megtekintések száma:

  157

  Generally, the most frequently used structural materials are metals which have high strength and stiffness. However, there are many cases when other important properties come to the front, as well as high deformation capacity with elastic behavior, high viscosity namely good damping effect. Due to its above mentioned properties, rubber is widely used in vehicle and automotive industry. Vehicle components made of rubber usually exhibit large deformations. Cyclic finite deformations generate temperature in hyperelastic materials. Furthermore it is necessary to take into consideration the effects of ambient temperature. The mechanical properties of rubber depend on temperature and temperature changes can accelerate chemical alteration processes which lead to the material deterioration and fatigue processes. Research on fatigue behavior and fatigue properties of rubber has a great significance for predicting fatigue life and improving durability of rubber products. There are several studies on the fatigue behavior of rubber-based materials, but there is less research in the fatigue life prediction considering the influence of temperature and temperature changes. First purpose of this paper is summarizing the influence of temperature and temperature changes on the fatigue behavior of rubber. The second purpose of this study is to provide an overview of the state of the art on the fatigue life prediction of rubber with primary focus on the different methods available for prediction of fatigue life under the influence of temperature and temperature changes.

• Exhaust System Muffler Volume Optimization of Light Commercial passenger Car Using Transfer Matrix Method

  132-138

  Mohamad Barhm

  Jalics Károly

  Kermani Milad

  Megtekintések száma:

  183

  Nowadays, the automotive industry is focused on weight and size reduction. Main advantage of this weight and size reduction are improving the fuel economy. The specific fuel consumption of a vehicle can be improved through e.g. downsizing area of heat loss, if we focus on vehicle with weight reduction. Weight reduction can be done by replacing material or by changing the size (dimensions) of components. In the present work we have focused on Audi A6 muffler, troubleshooting and optimizing the muffler by changing pipe length of inlet and outlet, also by replacing the original mesh plate to porous pipe. Based on optimization, prototype has been built with the help of 3D design tool CATIA V5 and the calculations of transmission loss (TL) have been performed by MATLAB. Plane wave-based models such as the transfer matrix method (TMM) can offer fast initial prototype solutions for muffler designers. The principles of TMM for predicting the transmission loss of a muffler was used. Result of this present study of an existing muffler has been analysed and then compared with vehicle level test observation data. Noise level have been optimized for new muffler design. Other literatures were played significant rule for validate our results.

• Parameter Estimation of Drag Coefficient and Rolling Resistance of Vehicles Based on GPS Speed Data

  109-115

  Szántó András

  Hajdu Sándor

  Megtekintések száma:

  145

  In this paper, a parameter estimation method of the model-based design approach is applied to estimate the drag coefficient and the rolling resistance coefficient of a vehicle. In fact, a constant-force parameter (c_const) and a velocity-square-force parameter (c_square) are in the vehicle model, and these result in the sum force applied along the translational DOF that models the vehicle. It is only an assumption that the constant force is the rolling resistance and the force proportional to the square of the velocity is the drag force of the air. Only GPS speed data is used for the estimation process. The conclusion is that parameter estimation is a good alternative when expensive measurement devices are not available to measure the force losses separately and directly.

• Simulation of BLDC Motor Drive Systems for Electric Vehicles Using Matlab Simulink

  48-52

  Dániel Nemes

  Hajdu Sándor

  Megtekintések száma:

  201

  The defining scientific developments of our time would not have been possible without the use of simulations. The aim of the research is to create a simulation of a BLDC motor. When creating a simulation, great emphasis must be placed on defining the purpose of the simulation. This basically determines the structure and complexity of the model. The model discussed here was created so that an optimization task could be defined more precisely by inserting it as a sub-model into a vehicle dynamics model. Scalability was another aspect, that is, to be able to increase the accuracy of the model with measured data in the future, as well as to be able to validate it. During the research, a BLDC motor efficiency map generation program was created, as well as an environment for testing the generated data. The created system gives researchers the opportunity to use a shape-correct efficiency model when simulating a BLDC motor even without measured data. This makes it possible to discover real relationships between model parameters when performing optimization.

   

• Optimization and Analysis of Structure about Lifting Device of Logistics Sorting

  425-431

  Zhao G

  Tiba Zsolt

  Menyhárt József

  Megtekintések száma:

  158

  The lifting device of a logistics sorting machine needs high frequency upward and downward reciprocating motion therefore the cutting fork arms and matching parts of the shaft are often worn out. In this paper the problem of the shear fork types applied for the lifting mechanism is studied at first. Then the advanced numerical simulation software ANSYS adopted for the lifting mechanism of the shear fork type, and the means of virtual simulation is introduced. Hence the possible location of faults and fault modes are analysed. Then improving measures about the lifting mechanism of the logistics sorting machine are suggested.

• The Effect of annealing temperature on corrosion resistance and microstructure of Zr-Sn-Nb-Fe alloy

  420-424

  Zhao G.

  Tiba Zsolt

  Menyhárt József

  Megtekintések száma:

  115

  The Ti-2Al-2.5Zr titanium alloy plate in beta phase water quench at different times of the reentry after annealing is implemented while primary phase number and size distribution of samples are obtained. This research is carried out on corrosion behavior in 3.5% [mass fraction] NaCl solution. Experimental study showed that after the beta phase water quenching Ti-2Al-2.5Zr titanium alloyed after 500 oC annealing when partial recrystallization happened. There seems to be lots of tiny dispersion in the alloy that was annealed with its samples of six-party [HCP] structure of Ti, Zr, Al phase 2 with the dimension below 100 nm. Reaching 500 oC when the rate of annealing at a primary phase of the sample at 550 oC is low 90% of the primary phase is less than 100 nm. The changing of the rule of present decreasing also triggers little difference overall. Precipitation in the process of annealing Zr [Nb,Fe,Cr] 2is less that proves to be good for corrosion resistance.

• Additív gyártástechnológia alkalmazása szélcsatornás szimulációkhoz

  62-71

  Pálfi Tamás

  Ficzere Péter

  Megtekintések száma:

  137

  Napjaink gazdasági szemlélete megköveteli többek között a reoülőgép üzemeltetőktől is, hogy egyre inkább a karbosemlegesség felé szervezzék át működésüket különböző innovatív technológiák bevezetésével.

  Jelen tanulmány célja, hogy mely innovatív formájának köszönhetően hozzájárul a repülőgépek üzemanyagfogyasztásának, ezáltal a légszennyezés lecsökkentéséhez.

• Frequency Domain Analysis of Tractor Tyre Enveloping Properties

  223-229

  Stojic Boris

  Megtekintések száma:

  77

  Main source of vibration excitation for off-road vehicles are ground profile undulations. Most unprepared terrains are characterized by wavelength of unevenness that is of the order of magnitude of the contact length between tire and ground, so that, due to its shape and elasticity, tire actually behaves as geometric low-pass filter transforming real road profile geometry into effective vehicle vibration excitation. Since this effective profile represents real vehicle excitation, it is of interest to study this filtering behaviour in more depth. In this work, investigation of this kind of tire response has been studied for agricultural tractor tire rolling quasistatically over singular road obstacle. Frequency analysis of road excitation and tyre response was carried out in order to obtain their spectra and frequency response function magnitude of the tyre as filter was obtained by dividing input by output spectra. Final assessment of frequency response function magnitude was obtained by averaging instances obtained for different dimensions of input obstacles.