Piotr Rybak

Prof. Piotr Rybak

orcid

Research Focus & Metrics

Academic Career Length

17Years (2010-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 January 2014 in Journal of KONES. Powertrain and Transport
Verified
Journal Article
Closed access
ZHZdzisław Hryciów
Zdzisław Hryciów
WBWacław Borkowski
Wacław Borkowski
PRPiotr Rybak
Piotr Rybak
JWJózef Wysocki
Józef Wysocki

11 November 2021 in Materials
Verified
Journal Article
Open access
PDF file
ZHZdzisław Hryciów
Zdzisław Hryciów
Jerzy MałachowskiJerzy Małachowski
Jerzy Małachowski
PRPiotr Rybak
Piotr Rybak
AWAndrzej Wiśniewski
Andrzej Wiśniewski
Modern wheeled armoured vehicles can perform a variety of tasks, making the development of weapon systems that can be safely and effectively integrated with the vehicle structure an area of interest. Due to the cost of implementing new models, it is more economical to test potential configurations using numerical methods, such as the finite element method. The numerical model has been validated to confirm the reliability of the obtained results. Modal tests were also performed using four configurations to identify the frequency and mode shape of natural vibrations occurring within the support structure. In an experimental setting, hull vibrations were forced using the modal hammer testing method. The modal assurance criterion (MAC) and the authors’ procedure were used to confirm the experimental and numerical test results. Additional testing in the form of impact loads was carried out for turret-containing structures. Structural strain at indicated points and forces transmitted by brackets to the bottom of the hull were compared.

23 May 2014 in Journal of KONES. Powertrain and Transport
Verified
Journal Article
Closed access
WBWacław Borkowski
Wacław Borkowski
ZHZdzisław Hryciów
Zdzisław Hryciów
PRPiotr Rybak
Piotr Rybak
JWJózef Wysocki
Józef Wysocki
AWAndrzej Wiśniewski
Andrzej Wiśniewski

1 January 2023 in Eksploatacja i Niezawodność – Maintenance and Reliability
Verified
Journal Article
Open access
ZHZdzisław Hryciów
Zdzisław Hryciów
PRPiotr Rybak
Piotr Rybak
MWMichał Wojciechowski
Michał Wojciechowski
PWPrzemysław Wachowiak
Przemysław Wachowiak
BKBartosz Kalicki
Bartosz Kalicki
The purpose of this study was to determine the effect of gas pressure and temperature on the spring characteristic of a HP strut used in a wheeled armoured personnel carrier. The research was performed based on a simulation model. Data to validate the model were obtained during experimental tests. The results indicate, among other things, that the friction generated in the seals is an important source of resistance force. Comparison of the simulation results with the measured characteristics indicates a proper modelling of the strut operation. Simulation studies have indicated that it is easy to modify the required suspension parameters by adjusting the initial gas pressure. A linear effect of pressure on static deflection can be assumed. Temperature has a strong influence on the spring characteristic. When it changes, significant changes in vehicle height are observed due to the lack of a compensation system. The temperature changes are not only due to changes in ambient temperature, but also by intense heating of the HP struts caused by the vehicle moving over rough terrain.

14 January 2023 in Acta Mechanica et Automatica
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Journal Article
Open access
PDF file
PRPiotr Rybak
Piotr Rybak
ZHZdzisław Hryciów
Zdzisław Hryciów
BMBogusław Michałowski
Bogusław Michałowski
AWAndrzej Wiśniewski
Andrzej Wiśniewski
The operation of high-speed tracked vehicles takes place in difficult terrain conditions. Hence, to obtain a high operational reliability, the design or modernisation process must be precise and should consider even the slightest details. The article presents issues related to the problem of formulating vehicle models using partial models of flexible elements used in tracked mechanisms. Changes occurring in the shape and properties of elements such as track pads and roadwheel bandages as a consequence of operating conditions are presented. These changes are reflected in the presented elastic–damping characteristics of components of the crawler mechanism. Numerical studies have shown that deterioration of chassis suspension components after a significant mileage may increase dynamic loads (forces) acting on the running gear. Increased forces in the running gear naturally result in increased stresses in the road surface on which the vehicle is travelling, which can pose a danger (or excessive wear and tear) to road infrastructure components such as culverts, bridges and viaducts. In the literature, model tests of objects are carried out on models that represent new vehicles, and the characteristics of the adopted elements correspond to elements not affected by the process and operating conditions. Its influence should not be ignored in the design, testing and running of a special vehicle. The tracked mechanism, as running gear, is designed for special high-speed vehicles for off-road and off-road driving. Its design ensures high off-road traversability. The dynamic loads originating from off-road driving are superimposed on those generated by the engine, drive train and interaction of the tracks with the roadwheels, sprocket, idler and supporting tracks return rollers.

30 December 2021 in The Archives of Automotive Engineering - Archiwum Motoryzacji
Verified
Journal Article
Open access
ZHZdzisław Hryciów
Zdzisław Hryciów
AWAndrzej Wiśniewski
Andrzej Wiśniewski
PRPiotr Rybak
Piotr Rybak
TTTomasz Tarnożek
Tomasz Tarnożek
This paper presents the results of experimental investigations of the effects of car wheel unbalance on driving safety and comfort. Basic information about types of wheel unbalance, their causes, and effects are included. The test subject was a BMW 3 Series car with rear-wheel drive. A specific unbalance was introduced on the front steered wheels. The vehicle was driven in a straight line on an asphalt road in good condition at speeds between 70 km/h and 140 km/h. During the test runs, acceleration waveforms were recorded from sensors placed on the lower control arm, driver's seat, and steering wheel. The vibration level of the unbalanced wheel increases with the driving speed and with the increase in unbalance. The highest increase in vibration amplitude occurred on the steering wheel at speeds between 100 km/h and 120 km/h. These vibrations have a direct effect on the driver. This is evidenced by negative driver perceptions such as fatigue and driving discomfort. This was also confirmed by the calculated vibration exposure levels. Driving with unbalanced wheels accelerates wear on the tyres, steering, drive, and suspension components of the vehicle.