Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

Wyszukujesz frazę "unsprung machines" wg kryterium: Temat


Wyświetlanie 1-6 z 6
Tytuł:
Active vibration reduction operator’s seat with the use of controlled single-acting pneumatic actuator
Autorzy:
Chwastek, S.
Powiązania:
https://bibliotekanauki.pl/articles/247371.pdf
Data publikacji:
2015
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
mobile heavy machines
unsprung vehicles
active reduction of vibration
controlled suspension seats
pneumatic actuator
Opis:
Mobile heavy machines produce vibrations with low natural frequencies. Because they tend to ride at low speeds, excitations due to road roughness excite low frequency vibrations, which can be reduced by active or semi active methods only. Under conditions of low frequency vibrations, energy dissipation in tires will reduce the vibration intensity in a minor degree only. In the unsprung mobile machine vibration isolation system are provided between a vibration source and the protected object (operator) along the path of vibration propagation. Most machines are now equipped with controlled suspension seats. In the case of active suspensions, the external energy source is required, for instance in the form of compressed air. The compressed air has the advantage that it is generally available in heavy machines as the working fluid and is environmentally friendly. Simulation tests were carried out both in the time domain in Matlab-Simulink and in the frequency domain in the program Mathcad. Simulation tests were performed to investigate effectiveness and stability of the proposed solution and the results were deemed satisfactory. The system was found to be feasible and implementable with respect to every parameter. The first purpose of this study is to develop a simulation model of the active suspension of operator's seat based on an adjustable pneumatic actuator. The other purpose of this study is to examine the effectiveness of different control strategies.
Źródło:
Journal of KONES; 2015, 22, 3; 13-19
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effectiveness of the active pneumatic suspension of the operator’s seat of the mobile machine in depend of the vibration reduction strategies
Autorzy:
Chwastek, S.
Pobędza, J.
Powiązania:
https://bibliotekanauki.pl/articles/245957.pdf
Data publikacji:
2018
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
unsprung mobile machines
active vibration reduction
controlled suspension seats
pneumatic actuator
Opis:
Low speeds of heavy mobile machines combined with large inertia result in the excitation of low frequency vibrations. Dissipation of vibration energy in the case of unsprung machines is performed only through tires, which slightly reduces the intensity of vibrations. Effective reduction of vibrations of mobile machines is possible only with active or semi-active methods. In unsprung mobile machines, on the way of propagation of vibrations between the source of vibrations and the protected object (machine operator), are vibroisolation systems located. These are most often controlled seat suspensions. In the case of the active suspensions, it is necessary to provide external energy, e.g. in the form of compressed air. The compressed air has the advantage that it is generally available in working machines as the working fluid and has its environmentally friendly properties (leaks do not contaminate the environment). This article is the result of the continuation of work on active methods of vibro-activity lowering in mobile machines, which resulted in, among others, elaboration of simulation model of the active operator’s seat suspension with controlled pneumatic actuator and its experimental identification. In particular, it was verifying the effectiveness of the adopted solution made the identification the friction model and thermodynamic phenomena in the controlled pneumatic cylinder. The aim of this work is parametric optimization of the suspension system and searching for the optimal control strategy. Experimental tests were carried out under conditions of harmonic excitations, coming from the electromechanical vibration exciter with controllable pitch and frequency. Data acquisition system and control circuit of the proportional directional control valve, supplying compressed air to the actuator were implemented using MATLAB-Simulink Real-Time software.
Źródło:
Journal of KONES; 2018, 25, 3; 93-98
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effectiveness of the active pneumatic suspension of the operator’s seat of the mobile machine in depend of the vibration reduction strategies
Autorzy:
Chwastek, S.
Pobędza, J.
Powiązania:
https://bibliotekanauki.pl/articles/244967.pdf
Data publikacji:
2018
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
unsprung mobile machines
active vibration reduction
controlled suspension seats
pneumatic actuator
Opis:
Low speeds of heavy mobile machines combined with large inertia result in the excitation of low frequency vibrations. Dissipation of vibration energy in the case of unsprung machines is performed only through tires, which slightly reduces the intensity of vibrations. Effective reduction of vibrations of mobile machines is possible only with active or semi-active methods. In unsprung mobile machines, on the way of propagation of vibrations between the source of vibrations and the protected object (machine operator), are vibroisolation systems located. These are most often controlled seat suspensions. In the case of the active suspensions, it is necessary to provide external energy, e.g. in the form of compressed air. The compressed air has the advantage that it is generally available in working machines as the working fluid and has its environmentally friendly properties (leaks do not contaminate the environment). This article is the result of the continuation of work on active methods of vibro-activity lowering in mobile machines, which resulted in, among others, elaboration of simulation model of the active operator’s seat suspension with controlled pneumatic actuator and its experimental identification. In particular, it was verifying the effectiveness of the adopted solution made the identification the friction model and thermodynamic phenomena in the controlled pneumatic cylinder. The aim of this work is parametric optimization of the suspension system and searching for the optimal control strategy. Experimental tests were carried out under conditions of harmonic excitations, coming from the electromechanical vibration exciter with controllable pitch and frequency. Data acquisition system and control circuit of the proportional directional control valve, supplying compressed air to the actuator were implemented using MATLAB-Simulink Real-Time software.
Źródło:
Journal of KONES; 2018, 25, 4; 43-48
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Model identification of active pneumatic vibration reduction operator’s seat of mobile machines
Autorzy:
Chwastek, S.
Pobędza, J.
Powiązania:
https://bibliotekanauki.pl/articles/244627.pdf
Data publikacji:
2016
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
unsprung machines
active reduction of vibration
controlled suspension seats
pneumatic actuator
Opis:
Low-frequency vibrations, generated in mobile machines during their driving, could be reduced only by use of active or semiactive methods. In conditions of low-frequency vibrations, energy dissipation in the machines tires slightly reduces the intensity of the vibration. Unsprung mobile machines are usually equipped with system of vibration isolation, which is located on the way of vibration propagation, between the vibration source and the protected object (the operator of the machine). Generally, controlled seat suspension is used. In the case of the active suspensions, it is necessary to provide external energy, e.g., in the form of compressed air. The compressed air has the advantage that it is generally available in working machines as the working fluid and has its environmentally friendly properties (leaks do not contaminate the environment). This article is the result of the continuation of work on active methods of vibro-activity lowering in mobile machines, which resulted in, among others, elaboration of simulation model of the active operator’s seat suspension with controlled pneumatic actuator. Currently aim of the study was experimental verification of the theoretical results; this verification was performed on the laboratory test bench. In the stand tests, special attention was paid on the assumed models of friction and thermodynamic phenomena in pneumatic actuator, as well as on the control system. Experimental tests were carried out under conditions of harmonic excitations, coming from the electromechanical vibration exciter with controllable pitch and frequency. Data acquisition system and control circuit of the proportional directional control valve, supplying compressed air to the actuator were implemented using Matlab-Simulink Real-Time software. Identification of the simulation model allows for getting the right parameters of the seat suspension. In addition, parametric optimization of the seat suspension system and functional optimization of control strategy would be possible in the next step.
Źródło:
Journal of KONES; 2016, 23, 4; 55-62
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Modulation effect of vibration frequency of an unsprung heavy machine under the variable road adhesion conditions
Autorzy:
Chwastek, S.
Powiązania:
https://bibliotekanauki.pl/articles/244951.pdf
Data publikacji:
2013
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
mobile heavy machines
unsprung vehicles
galloping effect
adhesion factor
slipping action
frequency modulation of vibration
Opis:
Mobile heavy machines as unsprung vehicles exhibit low dissipation ability, hence the ride even at low speeds may give rise to intensive vibration. Particularly dangerous situations occur when the road wheels break away from the road surface due to the ’galloping’ effect, being the result of excited vertical and angular vibration of the machine frame in the vertical plane of symmetry. That implies a major restriction on the ride velocity, which negatively impacts on the machine performance. Vibrations thus produced are mostly in the low-frequency range and hence energy dissipation in tyres will reduce the vibration intensity in a minor degree only. The motion of tired wheels will always involve some slipping. While investigating the feasibility of increasing the efficiency of the vibration reduction systems, one ought to take into account the variable adhesion of road wheels due to different dynamic loading acting on the vehicle axles during the ride. Observations of unsprung machines during the ride suggest the occurrence of self-excited vibration. Mobile machines constitute dynamic systems, which can be governed by nonlinear, sometimes non-stationary differential equations of motion. Their stability also depends on intensity of external vibrations. This study investigates the motion of unsprung mobile machines, taking into account the dynamic processes in the driving system under the conditions of the variable adhesion of road wheels. The model of interaction between a tired wheel and the terrain takes into account the relationship between the road wheel adhesion factor and the slipping action. Mathcad supported by Matlab-Simulink and in the frequency domain – simulations in the time domain. The purpose of the simulation procedure was to find the causes of the vibration modulation frequency and determine the conditions triggering the occurrence of self-excited vibrations. Simulations are supported by the analysis of motion stability.
Źródło:
Journal of KONES; 2013, 20, 4; 55-62
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Spatial model of the unsprung wheeled machine’s dynamic system
Autorzy:
Chwastek, S.
Powiązania:
https://bibliotekanauki.pl/articles/241952.pdf
Data publikacji:
2014
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
spatial model
dynamic system
mobile heavy machines
unsprung vehicles
"galloping" effect
"snake meandering” effect
adhesion factor
slipping action
vibration
differential gear
Opis:
Mobile heavy machines as unsprung vehicles exhibit low dissipation ability, hence the ride even at low speeds may give rise to intensive vertical and angular vibration. Vibrations thus produced are mostly in the low-frequency range and hence energy dissipation in tires will reduce the vibration intensity in a minor degree only. Particularly dangerous situations occur when the road wheels break away from the road surface due to the ’galloping’ effect. Kinematic excitation acting on the wheels is mostly uncorrelated stochastic (random) processes, giving rise to the "snake meandering" effect. That implies a major restriction on the ride velocity, which negatively affects the machine performance. The motion of tired wheels will always involve certain slipping. While investigating the feasibility of increasing the efficiency of the vibration reduction systems, one ought to take into account the variable adhesion of road wheels due to different dynamic loading acting on the vehicle axles during the ride. This study investigates the motion of unsprung mobile machines, taking into account the dynamic processes in the driving system under the conditions of the variable adhesion of road wheels. The model of interaction between a tired wheel and the terrain takes into account the relationship between the road wheel adhesion factor and the slipping action, as well as the impacts of the differential gear on distribution of drive torque. The 3D (spatial) model of a backhoe loader is considered. It is a two-axle self-propelled machine on a wheeled chassis. The mathematical model constitutes nonlinear and non-stationary differential equations of motion. Their stability is therefore associated with vibration intensity. Simulations in the time domain were supported by Matlab-Simulink. The purpose of this study is to improve the safety features during the ride of mobile heavy machines, basing on the parametric optimization of the model.
Źródło:
Journal of KONES; 2014, 21, 2; 45-52
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-6 z 6

    Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies