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1

Estymacja stanu układu dwumasowego z wykorzystaniem obserwatora wielowarstwowego

Wróbel Karol, Śleszycki Kacper, Szabat Krzysztof, Katsura Seiichiro

Przegląd Elektrotechniczny

|

2023

|

R. 99, nr 5

184--189

PL

W referacie przedstawiono zagadnienia związane z tłumieniem drgań skrętnych w układzie dwumasowym. W celu efektywnego tłumienia oscylacji wybrano strukturę z dwoma dodatkowymi sprzężeniami zwrotnymi. W celu jej implementacji konieczne jest zastosowanie wybranego estymatora zmiennych stanu. Problem estymacji komplikuje się w przypadku nieznanych warunków początkowych obiektu, np. naciągniętego wału. W niniejszej pracy proponuje się zastosowanie obserwatora wielowarstwowego zapewniającego znaczne skrócenie czasu estymacji.. Jego efektywność została potwierdzona przez szereg badań symulacyjnych i eksperymentalnych dla obiektu o parametrach zawartych w określonych granicach.

EN

The paper presents issues related to the damping of torsional vibrations in a dual mass system. In order to effectively dampen the oscillations, a structure with two additional feedbacks was chosen. In order to implement it, it is necessary to use the selected state variable estimator. The estimation problem becomes more complicated in the case of unknown initial conditions of the object, e.g. a stretched shaft. This paper proposes the use of a multilayer observer. Its effectiveness has been confirmed by a series of simulation and experimental tests for an object with parameters within certain limits.

2

Behaviour of a torsional vibration viscous damper in the event of a damper fluid shortage

Chmielowiec Andrzej, Michajłyszyn Adam, Homik Wojciech

Polish Maritime Research

|

2023

|

nr 2

105--113

EN

This article presents the analysis of a damping fluid deficiency in a torsional vibration viscous damper. The problem is analysed both qualitatively and quantitatively. Experimental results are presented, showing what happens to the damper in a situation where the design of the housing is inadequate and the inertia forces prevent the formation of an oil film. In addition, the article deals with the problem of the proper design of the oil channel and the dimensions required to enable the damper to operate reliably. The results of the article may be useful to the constructors of torsional vibration viscous dampers for marine engines.

3

Data-driven virtual sensor for powertrains based on transfer learning

Karhinen Aku, Hämäläinen Aleksanteri, Manngård Mikael, Miettinen Jesse, Viitala Raine

Bulletin of the Polish Academy of Sciences. Technical Sciences

|

2023

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Vol. 71, nr 6

art. no. e147061

EN

Variation in powertrain parameters caused by dimensioning, manufacturing and assembly inaccuracies may prevent model-based virtual sensors from representing physical powertrains accurately. Data-driven virtual sensors employing machine learning models offer a solution for including variations in the powertrain parameters. These variations can be efficiently included in the training of the virtual sensor through simulation. The trained model can then be theoretically applied to real systems via transfer learning, allowing a data-driven virtual sensor to be trained without the notoriously labour-intensive step of gathering data from a real powertrain. This research presents a training procedure for a data-driven virtual sensor. The virtual sensor was made for a powertrain consisting of multiple shafts, couplings and gears. The training procedure generalizes the virtual sensor for a single powertrain with variations corresponding to the aforementioned inaccuracies. The training procedure includes parameter randomization and random excitation. That is, the data-driven virtual sensor was trained using data from multiple different powertrain instances, representing roughly the same powertrain. The virtual sensor trained using multiple instances of a simulated powertrain was accurate at estimating rotating speeds and torque of the loaded shaft of multiple simulated test powertrains. The estimates were computed from the rotating speeds and torque at the motor shaft of the powertrain. This research gives excellent grounds for further studies towards simulation-to-reality transfer learning, in which a virtual sensor is trained with simulated data and then applied to a real system.

4

Application of fuzzy type II multi-layer Kalman filter for parameters identification of two-mass drive system

Śleszycki Kacper, Wróbel Karol, Szabat Krzysztof, Katsura Seiichiro

Bulletin of the Polish Academy of Sciences. Technical Sciences

|

2023

|

Vol. 71, nr 4

art. no. e146107

EN

The paper describes a novel online identification algorithm for a two-mass drive system. The multi-layer extended Kalman Filter (MKF) is proposed in the paper. The proposed estimator has two layers. In the first one, three single extended Kalman filters (EKF) are placed. In the second layer, based on the incoming signals from the first layer, the final states and parameters of the two-mass system are calculated. In the considered drive system, the stiffness coefficient of the elastic shaft and the time constant of the load machine is estimated. To improve the quality of estimated states, an additional system based on II types of fuzzy sets is proposed. The application of fuzzy MKF allows for a shorter identification time, as well as improves the accuracy of estimated parameters. The identified parameters of the two-mass system are used to calculate the coefficients of the implemented control structure. Theoretical considerations are supported by simulations and experimental tests.

5

Model of a Drive System for Low-Floor Trams with a Four-Linkage Coupling

Sanecki Henryk, Czauderna Tomasz

Problemy Kolejnictwa

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2022

|

Z. 196

137--149

EN

The article describes the structure and principles of operation of a drive system used in some low-floor trams. The system consists of electric motors, gear transmissions as well as hollow shaft s and four-linkage couplings causing the wheels to move. During the study, a dynamic model was built and the parameters needed to carry out a simulation were determined. NGT6 low-floor tram wagons operated by MPK S.A. Cracow were used as examples of existing vehicles. Due to the lack of available data, part of the work was devoted to determining mass moments of inertia of drive system components using an experimental method of torsional vibrations of a string. In subsequent chapters, a mathematical model was developed and a tram start-up simulation was performed based on specific parameters of the individual system components. Some of the results were presented in the form of graphs.

6

Vibration control of a rotating shaft by passive mass-spring-disc dynamic vibration absorber

Nguyen Duy Chinh

Archive of Mechanical Engineering

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2020

|

LXVII, nr 3

279--297

EN

Shaft is a machine element which is used to transmit rotary motion or torque. During transmission of motion, however, the machine shaft doesn’t always rotate with a constant angular velocity. Because of unstable current or due to sudden acceleration and deceleration, the machine shaft will rotate at a variable angular velocity. It is this rotary motion that generates the moment of inertial force, causing the machine shaft to have torsional deformation. However, due to the elasticity of the material, the shaft produces torsional vibration. Therefore, the main objective of this paper is to determine the optimal parameters of dynamic vibration absorber to eliminate torsional vibration of the rotating shaft that varies with time. The new results in this paper are summarized as follows: Firstly, the author determines the optimal parameters by using the minimum quadratic torque method. Secondly, the maximization of equivalent viscous resistance method is used for determining the optimal parameters. Thirdly, the author gives the optimal parameters of dynamic vibration absorber based on the fixed-point method. In this paper, the optimum parameters are found in an explicit analytical solutions, helping the scientists to easily find the optimal parameters for eliminating torsional vibration of the rotating shaft.

7

Estimation of state variables of the drive system with elastic joint using moving horizon estimation (MHE)

Serkies P.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2019

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Vol. 67, nr 5

883--892

EN

The article presents issues related to the application of a moving horizon estimator for state variables reconstruction in an advanced control structure of a drive system with an elastic joint. Firstly, a short review of the commonly used methods for state estimation in presented. Then, a description of a state controller structure follows. The design methodology based on the poles-placement method is briefly described. Next, the mathematical algorithm of MHE is presented and some crucial features of MHE are analysed. Then, selected simulation and experimental results are shown and described. The investigation shows, among others, the influence of window length on the quality of state variables estimation.

8

Experimental verification of the impact of a technical gas-using pneumatic coupling on torsional oscillation

Grega R., Krajňák J., Moravič M.

Zeszyty Naukowe. Transport / Politechnika Śląska

|

2018

|

z. 99

53--63

EN

The field of reducing torsional vibration of mechanical systems has seen the emergence of new flexible coupling designs. Our attention is focused on flexible pneumatic couplings. The flexible member of this coupling design is a pneumatic bag. The typical basic feature of such couplings is that the pneumatic bag allows for a change in air pressure. In the course of developing pneumatic couplings, we have experimented with the use of technical gases other than air for filling pneumatic bags. The aim has been to verify the impact of pneumatic couplings filled with other technical gases on the magnitude of torsional vibration in the mechanical system. For verification itself, two different gases have been used: helium, whose density is lower than air density, and propane butane, whose density is higher than air density. Experimental verification was performed under laboratory conditions on a mechanical system where torsion vibration was produced by a piston compressor.

9

Effect of torsional vibration on woodchip size distribution

Kaššay P.

Zeszyty Naukowe. Transport / Politechnika Śląska

|

2018

|

z. 99

95--104

EN

Nowadays, there is increasing demand for the use of renewable energy sources such as woodchips. One of the important qualitative parameters of woodchips is the size distribution. The aim of this article is to determine the effect of a woodchipper disc’s torsional vibration on the evenness of woodchip length, as well as propose a mathematical solution to this problem by assuming one harmonic component of disc speed and the uniform feed of chipped material. The presented mathematical solution can be used to determine the unevenness of woodchip length when the parameters of torsional vibration are known.

10

A brief overview about the development of torsional vibration calculation and education of methods for their calculation

Zoul V., Kováč P.

Zeszyty Naukowe. Transport / Politechnika Śląska

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2018

|

z. 99

205--211

EN

Torsional vibration calculation (TVC) is among the basic calculations that are required to support propulsion projects for various vehicles, ships and construction machines. A number of powerful software packages for these calculations already exists. However, the need to respect the physical properties of propulsion systems that are more complex than before has arisen. At the same time, knowledge about system properties and the capabilities of computing systems are also growing, resulting in an increase in new software systems, which could be used for these calculations. In this paper, these new trends are briefly described, with attention paid not only to practical use, but above all to how and to what extent these themes should be presented to students.

11

Semi-active torsional vibration isolation utilizing magnetorheological elastomer

Marzuki W. M. R. W., Muthalif A. G. A., Nordin N. H. D.

Vibrations in Physical Systems

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2018

|

Vol. 29

art. no. 2018014

EN

In rotating machinery, unattenuated excessive torsional vibration leads to damage and excessive wear. This type of vibration, which is transferred from one structure to another can be estimated using torsional transmissibility factor (TTF). The value of the TTF describes the ratio of output to input and reaches its peak at the natural frequency. Hence, the ability to vary coupling stiffness of two rotating shafts will allow the control of the TTF towards better performance and preventions from fatigue loading. Traditionally, passive rubbers are used as a flexible coupling in between two shafts. However, the constant passive stiffness of the material limits its performance. To address this issue, an adaptive coupling based on magnetorheological elastomer (MRE) is proposed to achieve better TTF at varying frequencies. Mathematical modelling, simulation study and experimental results of MRE for torsional vibration isolation are presented in this work. Natural frequency obtained from the TTF shows an increase of about 3 Hz when current changed from 1 to 6 A.

12

A novel predictive fuzzy adaptive controller for a two-mass drive system

Serkies P.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2018

|

Vol. 66, nr 1

37--47

EN

In the paper, a novel control structure based on the fuzzy logic and model predictive control methodologies for an elastic two-mass drive system is proposed. In order to reduce the computational requirements of the classical MPC methodology, the multi parametric programming (MPT) approach is used. The robustness of the system is ensured by implementation of three MPT controllers generated for different operation points and a supervisory fuzzy system. The main goal of the fuzzy system is suitable shaping of the control signal. The effectiveness of the proposed approach is checked in simulation and experimental tests. In order to show the properties of the proposed control structure, a critical comparison with an adaptive classical MPC controller is carried out. Both control structures are tested taking into account the performance and possibility of real-time implementation.

13

Optimal tuning of mechanical systems by application of a pneumatic tuner of torsional oscillation

Homišin J.

Zeszyty Naukowe. Transport / Politechnika Śląska

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2017

|

z. 97

47--55

EN

Reducing the dynamic load of any mechanical system can be achieved when the torsional vibration magnitude is optimized by applying a pneumatic tuner of torsional oscillation. Changing the torsional stiffness of a pneumatic tuner can be accomplished by changing the pressure of the gaseous medium, out of operation or during the operation of a mechanical system. This results in two suggested methods of tuning: (i) tuning of torsional oscillating mechanical systems that are out of operation, which fulfils the conditions for mechanical system tuning; (2) tuning mechanical systems during an operation in a steady state, thus ensuring the conditions of so-called continuous tuning of the given systems. The aim of this paper is to present the possibility of controlling torsional oscillation of a mechanical system that is out of operation by applying a tangential pneumatic tuner of torsional oscillation.

14

Harmonic analysis of torsional vibration force excitation

Urbanský M.

Zeszyty Naukowe. Transport / Politechnika Śląska

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2017

|

z. 97

181--187

EN

In our department, we deal with various methods for the continuous tuning of torsional oscillating mechanical systems during their operation, mainly in terms of torsional vibration magnitude. Therefore, in order to carry out necessary experimental research, we need torsional oscillation exciters, which operate on various principles. The objective of this paper is to conduct a harmonic analysis of a torsional oscillation force excitation mechanism, in order to identify the possibilities of its application.

15

Vibrations in Marine Power Transmission System

Doan D., Murawski L.

Zeszyty Naukowe Akademii Morskiej w Gdyni

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2017

|

nr 100

37--50

EN

Vibration analyses of marine machines and structures are one of the most important during the design process as well as during exploitation. Vibrations of ship hull (including superstructure and main engine body) are separately analysed from the vibrations of power transmission system. Vibrations of propulsion system include three types: lateral vibration, coupled axial vibration and torsional vibration. Among them, torsional vibrations are usually the most dangerous for the shaft line and the crankshaft. These vibrations may cause the increasing failure of the engine crankshaft as broken and bent shaft. Therefore, this article focuses on the study of torsional vibration of ship propulsion system. Calculation of torsional vibration of propulsion system with a medium-speed main engine is presented. The analysis is based on finite element method, with the code written in Matlab software. The result of this paper is applied for the tugboat with the engine of power 350 HP.

PL

Analizy drgań okrętowych maszyn i konstrukcji są jednymi z najważniejszych podczas procesu projektowania oraz ich eksploatacji. Drgania kadłuba statku (z nadbudówką i korpusem silnika głównego włącznie) są analizowane oddzielnie od drgań układu przeniesienia napędu. Wyróżnia się trzy typy drgań układu napędowego: drgania giętne, sprzężone wzdłużne oraz skrętne. Wśród nich drgania skrętne są zwykle najgroźniejsze dla linii wałów wału korbowego. Mogą one zwiększyć prawdopodobieństwo uszkodzenia wału korbowego poprzez jego złamanie lub wygięcie. Z tego powodu w artykule skupiono się na analizie drgań skrętnych okrętowych układów napędowych. Zaprezentowano obliczenia drgań skrętnych układu napędowego wyposażonego w średnioobrotowy silnik główny. Analizę przeprowadzono metodą elementów skończonych, której procedura została napisana w programie Matlab. Zastosowano ją do obliczeń holownika wyposażonego w silnik o mocy 350 HP.

16

The effect of damping coefficients on the torsional vibration of the damped multi-branch gears system

Firouzi J., Ghassemi H., Vakilabadi K. A., Khalilnezhad H.

Journal of Applied Mathematics and Computational Mechanics

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2017

|

Vol. 16, nr 4

5--16

EN

The effect of the damping coefficients has been considered to estimate the torsional vibration of the multi-branch gears systems. In this paper, the effect of the viscous damping between the gears and the fluid in which the gear is working and the effect of the structural damping of the shafts in a three-branched gear system is investigated. Initially, the governing equations were derived and then the damping effects were studied using MATLAB code. In order to validate the results which prepared by MATLAB code are compared with the other computational methods. To investigate the effects of the stiffness and damping on the shafts and gears, different gear branch systems are considered. Some of the vibration results on the damped gear branched systems with viscous damper and structural damper are analyzed and discussed.

17

Firing order selection for a V20 commercial diesel engine with FEV Virtual Engine

Buczek K., Lauer S.

Combustion Engines

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2017

|

R. 56, nr 2

64--70

EN

The continuously increasing mechanical and thermal loads of modern engines require optimization of the designs with incorporation of a wide range of different aspects. Application of advanced computer simulations in the development process for most engine components is well established, leading to the creation of well optimized products. However, the optimization of such design variables ike the firing order, which influences engine operation in several disciplines, is still challenging. Considering the ever increasing peak firing pressure requirements, the layout of the firing order in multi-cylinder commercial engines is an efficient way to reduce crank train / overall engine vibration and main bearing loads, whilst controlling engine balancing and preserving adequate gas exchange dynamics. The proposed general firing order selection process for four-stroke engines and, in particular, its first part being the optimization of the firing order based on crank train torsional vibration, is the main topic of this paper. The exemplary study for a V20 high speed commercial Diesel engine regarding the influence of the firing sequence on crank train torsional vibration has been conducted with the multibody dynamics simulation software “FEV Virtual Engine”. It addresses various engine crankshaft layouts and engine applications.

18

Dodatkowe kryteria wytrzymałościowe dotyczące bezpieczeństwa eksploatacyjnego połączenia wtłaczanego zestawu kołowego

Sobaś M.

Pojazdy Szynowe

|

2016

|

Nr 1

17--27

PL

W artykule przedstawiono dodatkowe kryteria wytrzymałościowe, decydują- ce o bezpieczeństwie zestawów kołowych pojazdów trakcyjnych oraz tocznych. Kryteria te obowiązują dla przeprowadzonego prawidłowego montażu zestawu kołowego. Przedstawiono aktualny stan wiedzy na temat drgań skrętnych oraz giętnych zestawu kołowego. Omówiono również kryteria, decydujące o wytrzymałości statycznej i zmęczeniowej złącza wtłaczanego.

19

Model aided design of tuned rubber TVD

Pankiewicz J., Chiliński B., Wądołowski M.

Journal of KONES

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2016

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Vol. 23, No. 4

367--374

EN

The rotation of a crankshaft in piston combustion engines results from the acting of tangential forces on the crank, whose value changes with the change of the angle of shaft rotation. This results in torsional vibrations. These vibrations become especially dangerous when the frequency of changes of any components of tangential force is near or equal to the natural frequency of the shaft. It leads to resonant amplification of vibration amplitude and to exceeding the limit values of the angle of shaft torsion. Most often in such cases, various types of torsional vibration dampers are used. In automotive industry, these are usually rubber vibration dampers. Typical torsional vibration damper is an example of a resonant damper, which is designed for the most dangerous resonant frequency of the crankshaft related to the first form of vibration for which the torsional vibrations usually have the greatest amplitude. The design of such a damper involves choosing the inertia moment of the flywheel and the parameters of viscous-elastic element. The article describes the model and the simulation research, which allowed for creating the procedure of designing rubber dampers of torsional vibrations. This procedure can help to reduce the costs of operation tests for the design of optimal torsional vibration damper.

20

The impact of complex forcing on the viscous torsional vibration damper’s work in the crankshaft of the rotating combustion engine

Jagiełowicz-Ryznar C.

International Journal of Applied Mechanics and Engineering

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2016

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Vol. 21, no. 4

1017--1023

EN

The numerical calculations results of torsional vibration of the multi-cylinder crankshaft in the serial combustion engine (MC), including a viscous damper (VD), at complex forcing, were shown. In fact, in the MC case the crankshaft rotation forcings spectrum is the sum of harmonic forcing whose amplitude can be compared with the amplitude of the 1st harmonic. A significant impact, in the engine operational velocity, on the vibration damping process of MC, may be the amplitude of the 2nd harmonic of a forcing moment. The calculations results of MC vibration, depending on the amplitude of the 2nd harmonic of the forcing moment, for the first form of the torsional vibration, were shown. Higher forms of torsional vibrations have no practical significance. The calculations assume the optimum damping coefficient VD, when the simple harmonic forcing is equal to the base critical velocity of the MC crankshaft.