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Wyszukujesz frazę "vehicle dynamic" wg kryterium: Temat


Wyświetlanie 1-13 z 13
Tytuł:
Motion of the long-haul articulated truck assembly with all wheels steered on the road curve
Autorzy:
Frankowski, J.
Powiązania:
https://bibliotekanauki.pl/articles/247584.pdf
Data publikacji:
2010
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
long-haul articulated vehicle dynamic model
vehicle curvilinear motion
Opis:
Currently, the majority of cargo transported by multi-axle long and heavy-haul motor vehicles, most of which have possibility of front axle wheels are steering only. In the case of performing the obstacle avoidance maneuver, the overtaking maneuver or the parking maneuver, they are a significant difficulty for the driver because of the width of the occupied road lane when the vehicle moves on the road curve, lane which is wider than greater is the front wheels steering angle and greater overall vehicle length. The occurrence of the ofexcessive lateral tire slip phenomenon when driving on curved road trach is the cause of accelerated wear of tire tread, which together with a large number of wheels would lead to higher operational costs ofsuch vehicles. This work using a spatial dynamic model of the vehicle consisting of a two-axle tractor and three-axle trailer with many degrees of freedom, with the possibility of all the wheels steering, moving on a road curve, is a qualitative analysis of the wheels steering problem aimed at the avoidance ofslip in the pneumatic tire - road surface coactions area. The model of coactions of pneumatic tire with the road surface, side drift included, together with accounting the phenomenon of asymmetrical loading of the vehicle chassis and drive train was adopted. Control for all the wheels steering should lead to an overlay or the maximum approximation of the front axle wheel tracks with the rear axles wheel tracks for the of articulated long-haul truck assembly moving on the road curve. The solution of model eąuations of motion for the vehicle considered will allow for the definition of the relationship between the front axle and rear axle wheels steering angles and velocity of movement of the mass centre of articulated haul truck assembly for the given set of design and operating parameters. The designation of the vehicle track will be possible.
Źródło:
Journal of KONES; 2010, 17, 4; 157-168
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The impact of the cannon on the combat vehicle chassis during firing
Autorzy:
Borkowski, W.
Figurski, J.
Walentynowicz, J.
Hryciów, Z.
Powiązania:
https://bibliotekanauki.pl/articles/241723.pdf
Data publikacji:
2007
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
combat vehicle
cannon
dynamic loads
mathematical model
numerical simulations
Opis:
In this paper the mathematical model of combat vehicle as well as mathematical models of input function generated by the cannon during firing and terrain unevenness was presented. This model enables the analysis of dynamic loads of the equipment mounted inside combat vehicle as well as analysis of dynamic loads of the crew. Parameters of the impulse forces acting on the vehicle during firing were determined on the theoretical basics of internal ballistic of cannon. The results of calculation were presented for hypothetical basic combat vehicle with a 125 mm and 73 mm calibre smoothbore gun. Firing during short stops and during combat vehicle motion at different speeds on terrain unevenness as well as angle of elevation of the gun barrel and rotation angle of the turret on the level of dynamic load were considered. A part of this paper was presented at the RTO AVT Symposium on "Functional and Mechanical Integration of Weapons and Land and Air Vehicles".
Źródło:
Journal of KONES; 2007, 14, 1; 49-61
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numerical study of dynamic response of reinforced concrete bridge induced by selected heavy vehicle
Autorzy:
Szurgott, P.
Smolarz, M.
Powiązania:
https://bibliotekanauki.pl/articles/244088.pdf
Data publikacji:
2016
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
dynamic test
bridge
vehicle
finite element method
LS-DYNA
Opis:
The main aim of this study is to carry out dynamic simulations of structural response of reinforced concrete bridge loaded with a moving heavy vehicle. Computational dynamics analysis was conducted using LS-DYNA computer code. The selected bridge was a reinforced-concrete structure located on the U.S. 90 in Northwest Florida. The bridge has six prestressed AASHTO type III beams and concrete deck. An 8-axle vehicle including a tractor unit and a low bed trailer were selected as a representative for the study. FE model of the tractor based on previous studies; however, a FE model of the trailer was developed for the present work. Analyses included passages of a vehicle with 47 tonnes cargo. A cargo resting on a trailer was taken into account by changing the material density of selected components in the semi-trailer FE model. Time histories of the bridge deflections in the middle of the span were recorded during the simulation tests. Simulations were performed for the vehicle velocity between 20 and 50 mph, stepped by 5 mph. An influence of the velocity on the bridge deflection was determined. The main objective of the simulation tests on the selected bridge was to assess the actual dynamic load allowance (DLA), also known as impact factor, based on the maximum deflection of the bridge span as a function of the vehicle velocity.
Źródło:
Journal of KONES; 2016, 23, 4; 505-512
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The research on dynamic loads and traction properties of military vehicles in the aspect of improvement of their structures
Autorzy:
Borkowski, W.
Rybak, P.
Hryciów, Z.
Wysocki, J.
Michałowski, B.
Wiśniewski, A.
Powiązania:
https://bibliotekanauki.pl/articles/247931.pdf
Data publikacji:
2015
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
military vehicle
dynamic loads
traction
model tests
experimental tests
Opis:
Since the beginning of the 90’s, a scientific team in the Motor Vehicle and Transport Institute of the Mechanical Department in the Military University of Technology, has been involved in the model and experimental tests of the existing structures of the military vehicles (tanks, combat infantry vehicles and wheeled armoured carriers) in the aspect of their modernization. A part of works is related to the military vehicles included in the army’s equipment and the other parts are related to newly designed vehicles. In both cases issues related to the behaviour of selected assemblies and the whole vehicle, structure during threats posed by the reality of contemporary battlefield or armed symmetric or asymmetric conflicts are analysed. Selected effects of the tests and analyses will be presented mostly within the qualitative scope due to the data sensitivity. Contemporary design of military vehicles requires involvement of various research methods and specialized calculation software. The results obtained during performed various experimental tests make a valuable basis for verification of numerical models used in design process and multi-option simulation calculations.
Źródło:
Journal of KONES; 2015, 22, 1; 37-46
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Multibody dynamic stability analysis of a diesel-hydraulic locomotive
Autorzy:
Mahyuddin, A. I.
Febriartanto, A. N.
Akbar, A.
Handoko, Y. A.
Powiązania:
https://bibliotekanauki.pl/articles/245508.pdf
Data publikacji:
2011
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
simulation of rail vehicle
locomotive
dynamic stability
critical speed
derailment
Opis:
In the development stage of a rail vehicle, analyses to evaluate its dynamic stability are required. In this work, a newly designed Diesel-Hydraulic Locomotive is modelled as a multibody system consisting of several rigid bodies interconnected by elastic elements. Multibody dynamic analysis of the system is performed to obtain the dynamic response and stability evaluation. Stability on tangent and curve tracks as well as the Locomotive dynamic response is investigated. The stability on tangent track is limited by the locomotive critical speed, Vcr, evaluated for various wheel conicity and primary suspension stiffness. Operation beyond this critical speed will result in hunting which could lead to wheel-climb. Stability evaluation on the curve track is conducted through simulation of the model negotiating a curve with rail irregularity for various radii. The maximum and minimum velocities for negotiating the curve are evaluated. To evaluate the derailment safety on the curve track, the wheel-rail contact force ratio in lateral and vertical directions (L/V), and the loading-unloading ratio of the primary suspension in the vertical direction are computed, and are compared to limiting criteria. The results are found to meet the safety criteria. The guiding lateral force on the wheel entering a curve track for various primary suspension stiffnesses is also evaluated because its effect on wear rate of the wheel and rail. While lower stiffness value of the primary suspension results in favourable L/V and lower guiding force, it yields lower critical speed on tangent track. Hence, a parametric study of the primary suspension stiffness is conducted to obtain optimum value which yield acceptable critical speed and guiding force, yet still meet the safety criteria.
Źródło:
Journal of KONES; 2011, 18, 3; 219-226
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Preliminary determination of the JET-2 unmanned aerial vehicle dynamic performances
Autorzy:
Kowaleczko, G.
Powiązania:
https://bibliotekanauki.pl/articles/247554.pdf
Data publikacji:
2014
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
unmanned aerial vehicle
JET-2 plane
aerodynamic characteristics
dynamic performances
Opis:
The paper presents result of theoretical analysis of the spatial dynamic performances for an unmanned aerial vehicle (UAV). This drone is designed and produced by consortium consisted of The Air Force Institute of Technology, The Military University of Technology, The Warsaw University of Technology and The MSP enterprise. A plane JET-2 is the jet-powered airplane dedicated for Polish Military Forces. It will be used in the training process of anti-aircraft crews. Because of high level of requirements (maximum speed, stall speed, climb rate, range and endurance), it has been designed as the jet-powered aircraft. This plane will perform autonomous flights and therefore it should be stable in all phases of flight – static and dynamic stability is desirable. Therefore, the theoretical analysis focused on the stability performances have been performed, parallel to laboratory tests. They were done using nonlinear mathematical model of the JET-2. This model will be described in the paper as well as selected results of numerical simulations. The UAV JET-1 parameters and main parts of the system with the performances as the take-off mass 80 kg, the maximum speed 150 m/s, the endurance 60 min, the altitude 5000 m are presented in the paper.
Źródło:
Journal of KONES; 2014, 21, 4; 256-262
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numerical analysis of the front impact between two shunting locomotives
Autorzy:
Dziewulski, P.
Konarzewski, M.
Szurgott, P.
Powiązania:
https://bibliotekanauki.pl/articles/245458.pdf
Data publikacji:
2014
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
finite element method
dynamic analysis
crash test
railway vehicle
LS-DYNA
Opis:
The main aim of this study is to carry out dynamic finite element analysis of a crash between two identical shunting locomotives. Numerical simulations include front-end impact of the running locomotive with a stationary one situated on the track. The first design collision scenario includes such obstacle for railway vehicles operated on national and regional networks. A considered locomotive based on a popular Polish shunting locomotive – SM42. However, the tested locomotive was slightly modernized in comparison with the original one. Finite element model of the locomotive was developed by the authors. FE analyses were carried out according to the PN-EN 15227 standard, which provides crashworthiness requirements for railway vehicle bodies. LESS-DYNA computer code was used for the simulations. The energy balance was initially checked in order to confirm the accuracy of analysis. The paper presents selected results of analyses focused on the locomotive frame behaviour. Contours of effective stress for selected moments of time are presented. Time histories of selected parameters are also depicted. The current study is a part of the project focused on modernization of the SM42 locomotive. Therefore, it is required to evaluate the locomotive behaviour during the impact test. Dynamic numerical simulation is acceptable since the experimental tests on the complete objects under consideration are impractical and impossible at the moment.
Źródło:
Journal of KONES; 2014, 21, 3; 81-88
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numerical analysis of impact between shunting locomotive and selected road vehicle
Autorzy:
Dziewulski, P.
Stankiewicz, M.
Szurgott, P.
Powiązania:
https://bibliotekanauki.pl/articles/245955.pdf
Data publikacji:
2014
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
finite element method
dynamic analysis
crash test
railway vehicle
LS-DYNA
Opis:
The main aim of this study is to carry out dynamic finite element analysis of a crash between shunting locomotive and selected road vehicle. Numerical simulations include side impact of the running locomotive in the vehicle situated across the track. A considered locomotive based on a popular Polish shunting locomotive – SM42. However, the tested locomotive was slightly modernized in comparison with the original one. Finite element model of the locomotive was developed by the authors whereas the vehicle FE model was download from the free database of such models. FE analysis was carried out according to the PN-EN 15227 standard which provides crashworthiness requirements for railway vehicle bodies. 15 tons large truck was selected as a representative for the study. One of the design collision scenario includes such deformable obstacle for railway vehicles operated on national and regional networks. LS-DYNA computer code was used for the simulations. The paper presents selected results of analysis generally focused on the locomotive frame behaviour. Contours of stress for selected moments of time are presented. Moreover, time histories of selected parameters are depicted. The energy balance was also checked in order to confirm the accuracy of analysis. The current study is a part of the project focused on modernization of the SM42 locomotive. Therefore, it is required to evaluate the locomotive behaviour during the impact test. Dynamic numerical simulation are acceptable since the experimental tests on the complete objects under consideration are impractical and impossible at the moment.
Źródło:
Journal of KONES; 2014, 21, 4; 87-94
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Simulations of front impact between two shunting locomotives at different velocities
Autorzy:
Szurgott, P.
Kozioł, Ł.
Powiązania:
https://bibliotekanauki.pl/articles/244509.pdf
Data publikacji:
2016
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
finite element method
dynamic analysis
crash test
railway vehicle
LS-DYNA
Opis:
The main aim of this study is to carry out dynamic simulations of a crash between two identical shunting locomotives running at different velocities. Numerical analyses using a Finite Element Method (FEM) include front-end impact of the running locomotive with a stationary one situated on the track. Such collision scenario is required for railway vehicles operated on national and regional networks. A considered locomotive based on a Polish shunting locomotive – SM42, however the tested locomotive was slightly modernized. Finite element model of the locomotive was developed by the authors. FE analyses were conducted according to the PN-EN 15227 standard, which provides crashworthiness requirements for railway vehicle bodies. LS-DYNA computer code was used for the simulations. The paper presents selected results of analyses focused on the locomotive frame behaviour. Simulations were performed for the vehicle between 20 and 90 km/h. An influence of the impact velocity on some output quantities was determined. Contours of effective stress for selected moments of time as well as time histories of selected values are depicted. For modernized locomotives, it is required to evaluate their behaviour during the impact test. Dynamic numerical simulation is acceptable since the experimental tests on the complete objects under consideration are impractical and impossible sometimes.
Źródło:
Journal of KONES; 2016, 23, 2; 381-388
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numerical analysis of collision between locomotive and passenger car located on level crossing
Autorzy:
Szurgott, P.
Dziewulski, P.
Powiązania:
https://bibliotekanauki.pl/articles/246815.pdf
Data publikacji:
2014
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
finite element method
dynamic analysis
collision
railway vehicle
passenger car
LS-DYNA
Opis:
The main aim of this study is to carry out dynamic finite element analysis of a collision between shunting locomotive and a passenger car. Numerical simulations include side impact of the running locomotive in the vehicle situated across the track on a level crossing. A considered locomotive based on a popular diesel-electric shunting locomotive SM42 but it was slightly modernized in comparison with the original. Finite element model of the locomotive was developed by the authors whereas the vehicle FE model was download from the National Crashworthiness Analysis Center database and it was dedicated to the crash/impact analyses. FE analysis was carried out according to the PN-EN 15227 standard which provides crashworthiness requirements for railway vehicle bodies. However, additional objective of the analysis was to evaluate the behaviour of a small passenger car during the side impact with about 70-ton locomotive. A subcompact passenger car – Geo Metro – was selected as a representative for the study. One of the design collision scenario impact into low obstacle for railway vehicles operated on national and regional networks. LS-DYNA computer code was used for the simulations. The paper presents selected results of analysis generally focused on the locomotive frame behaviour. Contour of stress for the moment of time is presented. Moreover, time histories of selected parameters are depicted. The energy balance was also checked in order to confirm the accuracy of analysis.
Źródło:
Journal of KONES; 2014, 21, 4; 489-496
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Design of a new engine dynamometer test stand for driving cycle simulation
Autorzy:
Kęder, M.
Grzeszczyk, R.
Merkisz, J.
Fuć, P.
Lijewski, P.
Powiązania:
https://bibliotekanauki.pl/articles/246315.pdf
Data publikacji:
2014
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
dynamic engine test stand
combustion engine
variable frequency drive
induction motor
vehicle model
Opis:
Dynamic combustion engine test stand allows a very accurate analysis of the engine work. The prototype of such a system was developed and built in a cooperation of Poznan University of Technology with the ODIUT Automex company. The system consists of an asynchronous motor controlled by a regenerative variable-frequency drive with an ability to return braking energy back to the power system. Together they permit to set very precise work points of the combustion engine in every time moment, unlike test stands with eddy current dynamometer, which are only able to brake the engine. Measuring system is used to gather data from all sensors, especially torque sensor, which records the torque on a drive shaft. Sensors are connected to electronic boards, which provide signal processing, and data acquisition. Fuel mass flow meter with temperature and pressure control allows regulating the parameters of fuel supplied to the engine. A set of applications is used for test stand management and data presentation and visualization. Real conditions and vehicle dynamics are emulated using advanced models to allow a comprehensive research of the combustion engine on the test stand. The paper covers the description of developed system, its components, software and models adapted in emulation. Moreover, it provides schematics of the system as well as a block diagram of the vehicle dynamic model.
Źródło:
Journal of KONES; 2014, 21, 4; 217-224
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Development of finite element model of shunting locomotive applicable for dynamic analyses
Autorzy:
Dziewulski, P.
Szurgott, P.
Powiązania:
https://bibliotekanauki.pl/articles/247466.pdf
Data publikacji:
2014
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
finite element method
modelling
dynamic analysis
crash test
railway vehicle
LS-DYNA
HyperMesh
Opis:
The main aim of this study is to develop a finite element model of the hybrid-shunting locomotive. Considered locomotive is based on a popular shunting locomotive in Poland – SM42. All components above the locomotive frame could be modified in comparison to the original object, whereas a chassis was essentially unchanged. Such solution allows the operators freely configure components e.g. diesel engine, generator, cooling module, cab etc., according to their own requirements. Works on the FE model were focused on very accurate reflection of the locomotive frame since the planned dynamic analyses include crash tests. FE model of the frame has a fine mesh and it is considered as a deformable component. Other segments of the vehicle are simplified and treated as rigid bodies mostly. FE model was developed on the basis of the locomotive CAD model. It was decided to transform the CAD model of the frame into the FE one applying the midsurface procedure. Such approach is correct since the locomotive frame is made of a large number of steel elements in the form of sheet metal plates and sections welded together. Altair Hyper Mesh software was used in the FE model developing process. Appropriate connections between respective components of the model e.g. wheelset – bogie, bogie – locomotive frame, were applied. Finally, the locomotive FE model consists of about 116 thousands of finite shell and solid elements and about 125 thousands of nodes. Dynamic analyses of the locomotive FE model will be carried out using LS-DYNA computer code.
Źródło:
Journal of KONES; 2014, 21, 4; 95-102
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influence of dynamic load on military vehicles construction
Wpływ obciążeń dynamicznych na budowę pojazdów wojskowych
Autorzy:
Simiński, P.
Stryjek, P.
Powiązania:
https://bibliotekanauki.pl/articles/241969.pdf
Data publikacji:
2007
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
obciążania dynamiczne
obciążania udarowe
badania eksperymentalne
pojazd
dynamic load
impact load
experimental researches
vehicle
Opis:
W artykule przedstawiono wpływ obciążeń udarowych i dynamicznych na konstrukcje pojazdów. Autorzy skoncentrowali się w głównej mierze na pojazdach terenowych i wojskowych, ponieważ warunki w jakich są eksploatowane powodują, że są one najczęściej narażone na obciążenia udarowe. W artykule pokazano przykłady wpływu obciążeń dynamicznych pochodzących od nierówności drogi na konstrukcje pojazdu. Ponadto zwrócono również uwagę na inne możliwe źródła obciążeń dynamicznych występujące w procesie eksploatacji. Przedstawiono także praktyczne uszkodzenia, które powstały na skutek wspomnianych obciążeń od innych źródeł. Uszkodzenia te wynikają zarówno z przekroczenia doraźnej wytrzymałości konstrukcji, jak i często z przyjęcia przez konstruktorów, już na etapie projektowania, błędnych rozwiązań. W kolejnej części zwrócono uwagę na rozwiązania konstrukcyjne oraz sposoby zapobiegania uszkodzeniom, mające na celu zabezpieczyć konstrukcje pojazdu i pasażerów, przed negatywnym skutkiem obciążeń udarowych. Niniejszy artykuł ma na celu przekazanie praktycznych uwag na temat wpływu obciążeń dynamicznych na konstrukcje pojazdów. Wszystkie z przykładów wpływu obciążeń dynamicznych na konstrukcje pojazdów, przedstawionych w artykule, pochodzą z praktyki badawczej i często dotyczą one pojazdów specjalnych lub konstrukcji prototypowych. Pojazdy wojskowe powinny być zabezpieczone przed wszelkiego rodzaju obciążeniami udarowymi, które mogą wystąpić podczas eksploatacji, a w wypadku przekroczenia wytrzymałości poszczególnych elementów, pojazd powinien być możliwy do naprawienia siłami wojskowych jednostek remontowych, nawet w warunkach poligonowych.
The article presents influence of dynamic load on construction military vehicles. The authors concentrated their attention on off road and military vehicles, because they operated in hard condition and are endanger to load impact. The article presents examples of influence the dynamic load on bump's road. Additionally, authors take note of another sources dynamics load during operation. Showed also practise damages as a result of dynamics load from different sources. These damages are result from over durability and engineer mistakes in construction procedure. In next part of articles the authors take note of construction solutions and ways prevent to damages. These solutions have been protecting crew to negative result of dynamics load and impact load. The article additionally takes note of practise experience from vehicle operation. All examples to coming from testing practise and often concern to prototypes and special vehicles. Military vehicles should be safe against all manner of impact loads which can appear during working, and in the case of excess strength particular elements, the vehicle should be retrievable the vehicle should be been by retrievable by military repair troops, even in range conditions.
Źródło:
Journal of KONES; 2007, 14, 1; 343-348
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-13 z 13

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