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Tytuł:
Synteza sterowania nieliniowych układów śledzenia przy braku znajomości dynamiki obiektu
Tracking System Nonlinear Control Synthesis Under a Lack of Object Dynamical Model
Autorzy:
Zwierzewicz, Z.
Borkowski, P.
Powiązania:
https://bibliotekanauki.pl/articles/360563.pdf
Data publikacji:
2006
Wydawca:
Akademia Morska w Szczecinie. Wydawnictwo AMSz
Tematy:
systemy nieliniowe
reżim ślizgu
adaptacja
stabilizacja kursu statku
EXPLO-SHIP 2006
nonlinear systems
sliding mode control
adaptation
ship course keeping
Opis:
W artykule dokonano syntezy sterowania nieliniowego układu śledzenia trajektorii, w sytuacji braku znajomości nieliniowej funkcji modelu obiektu, opartego na metodzie reżimu ślizgu. Wskazano, że zaprezentowane podejście daje się bezpośrednio uogólnić w sposób bardziej znacznie zaawansowany, polegający na adaptacyjnej aproksymacji nieznanej funkcji z pomocą AI aproksymatorów. Działanie systemu zilustrowano na przykładzie zadania stabilizacji kursu statku.
The paper refers to the tracking system nonlinear control synthesis via the sliding mode control where it is assumed that there is an unknown nonlinear function in the object model. It has been pointed out that the presented approach may be directly generalized to the much more advanced case, consisting in adaptive approximation of unknown function by means of AI aproximators. The system operation has been illustrated with an example of ship course keeping problem.
Źródło:
Zeszyty Naukowe Akademii Morskiej w Szczecinie; 2006, 11 (83); 413-424
1733-8670
2392-0378
Pojawia się w:
Zeszyty Naukowe Akademii Morskiej w Szczecinie
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Wear Assessment of Sliding Sleeves in a Single-Stage Cycloidal Drive
Autorzy:
Żurowski, Wojciech
Olejarczyk, Krzysztof
Zaręba, Renata
Powiązania:
https://bibliotekanauki.pl/articles/102727.pdf
Data publikacji:
2019
Wydawca:
Stowarzyszenie Inżynierów i Techników Mechaników Polskich
Tematy:
single-stage cycloidal drive
wear
sliding sleeves
synthetic oil
jednostopniowy napęd cykloidalny
zużycie
rękawy przesuwne
olej syntetyczny
Opis:
In the paper, the issue of sliding sleeves wear in a cycloidal transmission was addressed. The working model of a cycloidal drive was constructed and tested in the special rig, and its sleeves underwent detailed analysis afterwards. The sleeves were produced by the sintering technique out of Selfoil bronze with self-lubricating properties. In particular, their surface appearance, weight loss and dimensional changes were assessed; as additionally, the chemical content of the gearbox oil was analyzed. The differences in the sleeves wear were pointed out, related to their positions in the transmission.
Źródło:
Advances in Science and Technology. Research Journal; 2019, 13, 4; 239-245
2299-8624
Pojawia się w:
Advances in Science and Technology. Research Journal
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Fault identification in underwater vehicle thrusters via sliding mode observers
Autorzy:
Zuev, Alexander
Zhirabok, Alexey
Filaretov, Vladimir
Powiązania:
https://bibliotekanauki.pl/articles/1838162.pdf
Data publikacji:
2020
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
underwater vehicle
thruster
fault identification
sliding mode observer
pojazd podwodny
identyfikacja uszkodzenia
sterowanie ślizgowe
Opis:
The paper is devoted to the problem of increasing the efficiency of underwater vehicles by using a fault diagnosis system for their thrusters which provides detection, isolation, and identification of minor faults. To address the problem, a two-stage method is proposed. At the first stage, a bank of diagnostic observers is designed to detect and isolate the emerging faults. Each observer in this bank is constructed to be sensitive to some set of faults and insensitive to others. At the second stage, additional observers working in sliding mode are synthesized in order to accurately estimate the error value in the signal obtained from the angular velocity sensor and to estimate deviations of the thruster parameters from their nominal values due to the faults. In contrast to the existing solutions, reduced-order (i.e., lower-dimensional) models of the original system are proposed as a basis to construct sliding mode observers. This approach permits reduction of the complexity of the obtained observers in comparison with the known methods, where full-order observers are constructed. The simulation results show the efficiency and high quality of all synthesized observers. In all cases considered, it was possible to detect typical faults, as well as estimate their values.
Źródło:
International Journal of Applied Mathematics and Computer Science; 2020, 30, 4; 679-688
1641-876X
2083-8492
Pojawia się w:
International Journal of Applied Mathematics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The effect of the exposure-in-oil on the contact angle of the polymers forming sliding layers in hydrodynamic bearings
Wpływ ekspozycji w oleju na kąt zwilżania polimerów stosowanych na warstwy ślizgowe w łożyskach hydrodynamicznych
Autorzy:
Zorn, J.
Wasilczuk, M.
Powiązania:
https://bibliotekanauki.pl/articles/971605.pdf
Data publikacji:
2016
Wydawca:
Stowarzyszenie Inżynierów i Techników Mechaników Polskich
Tematy:
hydrodynamic thrust bearings
polymer-sliding layers
contact angle
wetting
łożyska hydrodynamiczne wzdłużne
polimerowe warstwy ślizgowe
kąt zwilżania
zwilżanie
Opis:
Polymers used as the sliding layers of hydrodynamic thrust bearings are typically thermoplastics characterized by relatively high values of contact angles when compared with metals. Metals, including Babbitt, or other bearing alloys, are characterized by low values of the contact angles. The lower the angle, the better the surface is wetted. Plastics used in tribological pairs to ensure a lower coefficient of friction, that is, for example, polytetrafluoroethylene (PTFE) or its composites, have several times higher contact angles compared to the bearing alloys. The research described below shows the effect of the exposure-in-oil contact angle of the polymer layer applied on a hydrodynamic sliding bearing. The conducted study showed the beneficial effects of oil on the reduction of the contact angle.
Polimery stosowane jako warstwy ślizgowe w hydrodynamicznych łożyskach wzdłużnych to zazwyczaj tworzywa termoplastyczne charakteryzujące się relatywnie wysokimi wartościami kątów zwilżania w porównaniu z metalami. Metale, w tym również Babbitt czy inne stopy łożyskowe, cechują niskie wartości kątów zwilżania. Im niższy kąt, tym powierzchnia lepiej się zwilża. Tworzywa sztuczne wykorzystywane w węzłach tribologicznych mających zapewnić jak niższy współczynnik tarcia, czyli na przykład politetra-fluoroetylen lub jego kompozyty cechują kilkukrotnie wyższe wartości kątów zwilżania w porównaniu ze stopami łożyskowymi. W opisanym poniżej badaniu przedstawiono wpływ ekspozycji w oleju na kąt zwilżania polimerów stosowanych na warstwy ślizgowe w łożyskach hydrodynamicznych. Przeprowadzone badanie pokazało korzystny wpływ oleju na obniżenie kąta zwilżania.
Źródło:
Tribologia; 2016, 269, 5; 219-227
0208-7774
Pojawia się w:
Tribologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Motion control and collision avoidance algorithms for unmanned surface vehicle swarm in practical maritime environment
Autorzy:
Zhuang, Jiayuan
Zhang, Lei
Qin, Zihe
Sun, Hanbing
Wang, Bo
Cao, Jian
Powiązania:
https://bibliotekanauki.pl/articles/260012.pdf
Data publikacji:
2019
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
USV
swarm control
collision avoidance
sliding mode
artificial potential field
Opis:
The issue of controlling a swarm of autonomous unmanned surface vehicles (USVs) in a practical maritime environment is studied in this paper. A hierarchical control framework associated with control algorithms for the USV swarm is proposed. In order to implement the distributed control of the autonomous swarm, the control framework is divided into three task layers. The first layer is the tele-operated task layer, which delivers the human operator’s command to the remote USV swarm. The second layer deals with autonomous tasks (i.e. swarm dispersion, or avoidance of obstacles and/or inner-USV collisions), which are defined by specific mathematical functions. The third layer is the control allocation layer, in which the control inputs are designed by applying the sliding mode control method. The motion controller is proved asymptotically stable by using the Lyapunov method. Numerical simulation of USV swarm motion is used to verify the effectiveness of the control framework.
Źródło:
Polish Maritime Research; 2019, 1; 107-116
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Sliding mode observers for fault identification in linear systems not satisfying matching and minimum phase conditions
Autorzy:
Zhirabok, Alexey
Zuev, Alexander
Filaretov, Vladimir
Shumsky, Alexey
Powiązania:
https://bibliotekanauki.pl/articles/1409401.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
linear systems
faults
identification
disturbances
sliding mode observer
Opis:
The paper studies the fault identification problem for linear control systems under the unmatched disturbances. A novel approach to the construction of a sliding mode observer is proposed for systems that do not satisfy common conditions required for fault estimation, in particular matching condition, minimum phase condition, and detectability condition. The suggested approach is based on the reduced order model of the original system. This allows to reduce complexity of sliding mode observer and relax the limitations imposed on the original system.
Źródło:
Archives of Control Sciences; 2021, 31, 2; 253-266
1230-2384
Pojawia się w:
Archives of Control Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Application of fractional calculus in iterative sliding mode synchronization control
Autorzy:
Zhang, Xin
Wen-Ru, Lu
Zhang, Liang
Xu, Wen-Bo
Powiązania:
https://bibliotekanauki.pl/articles/141629.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
cross-coupling control
fractional calculus
iterative learning control
PD control
robot arm
sliding mode control
Opis:
In order to control joints of manipulators with high precision, a position tracking control strategy combining fractional calculus with iterative learning control and sliding mode control is proposed for the control of a single joint of manipulators. Considering the coupling between joints of manipulators, a fractional-order iterative sliding mode crosscoupling control strategy is proposed and the theoretical proof of its progressive stability is given. The paper takes a two-joint manipulator as the research object to verify the control strategy of a single-joint manipulator. The results show that the control strategy proposed in this paper makes the two-joint mechanical arm chatter less and the tracking more accurate. The synchronous control of the manipulator is verified by a three-joint manipulator. The results show that the angular displacement adjustment times of the threejoint manipulator are 0.11 s, 0.31 s and 0.24 s, respectively. 3.25 s > 5 s, 3.15 s of a PD cross-coupling control strategy; 2.85 s, 2.32 s, 4.22 s of a PD iterative cross-coupling control strategy; 0.14 s, 0.33 s, 0.28 s of a fractional-order sliding mode cross-coupling control strategy. The root mean square error of the position error of the designed control strategy is 6.47 × 10−6 rad, 3.69 × 10−4 rad, 6.91 × 10−3 rad, respectively. The root mean square error of the synchronization error is 3.96×10−4 rad, 1.36×10−3 rad, 7.81×10−3 rad, superior to the other three control strategies. The results illustrate the effectiveness of the proposed control method.
Źródło:
Archives of Electrical Engineering; 2020, 69, 3; 499-519
1427-4221
2300-2506
Pojawia się w:
Archives of Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Research on beam supply control strategy based on sliding mode control
Autorzy:
Zhang, Hao
Dong, Haiying
Zhang, Baoping
Wu, Tong
Chen, Changwen
Powiązania:
https://bibliotekanauki.pl/articles/141014.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
beam supply
DC/DC converter
robustness
sliding mode control
Opis:
In the hybrid multiple H-bridge topology of beam supply, the load change of a DC/DC full-bridge converter can greatly affect the output voltage during onsite operation. An improved sliding mode control (SMC) strategy is thus proposed in this paper, where the rate of switching control is added to the law of system equivalent control to create a law that can realize a complete sliding mode control. Considering the special operating conditions of the load can have an influence on the performance of the controller, the impact of uncertainty existing in onsite conditions is suppressed with the proposed strategy utilized. The validity of the proposed strategy, finally, is verified by simulation, which proves the outperformance of the system in both robustness and dynamics.
Źródło:
Archives of Electrical Engineering; 2020, 69, 2; 349-364
1427-4221
2300-2506
Pojawia się w:
Archives of Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Backstepping sliding mode controller improved with fuzzy logic: Application to the quadrotor helicopter
Autorzy:
Zeghlache, S.
Saigaa, D.
Harrag, A.
Kara, K.
Bouguerra, A.
Powiązania:
https://bibliotekanauki.pl/articles/229480.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
fuzzy sliding mode
backstepping
quadrotor helicopter
dynamic modeling
Opis:
n this paper we present a new design method for the fight control of an autonomous quadrotor helicopter based on fuzzy sliding mode control using backstepping approach. Due to the underactuated property of the quadrotor helicopter, the controller can move three positions (x;y; z) of the helicopter and the yaw angle to their desired values and stabilize the pitch and roll angles. A first-order nonlinear sliding surface is obtained using the backstepping technique, on which the developed sliding mode controller is based. Mathematical development for the stability and convergence of the system is presented. The main purpose is to eliminate the chattering phenomenon. Thus we have used a fuzzy logic control to generate the hitting control signal. The performances of the nonlinear control method are evaluated by simulation and the results demonstrate the effectiveness of the proposed control strategy for the quadrotor helicopter in vertical flights.
Źródło:
Archives of Control Sciences; 2012, 22, 3; 315-342
1230-2384
Pojawia się w:
Archives of Control Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Control and optimisation of photovoltaic water pumping system using sliding mode
Autorzy:
Zarour, L.
Abed, K.
Hacil, M.
Borni, A.
Powiązania:
https://bibliotekanauki.pl/articles/200899.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
photovoltaic pumping system modelling
optimization
maximum power point
MPPT
sliding mode control
optymalizacja
maksymalny punkt mocy
Opis:
A sliding mode controller for the photovoltaic pumping system has been proposed in this paper. This system is composed of a?photovoltaic generator supplying a?three-phase permanent magnet synchronous motor coupled to a?centrifugal pump through a?three-phase voltage inverter. The objective of this study is to minimise the number of regulators and apply the sliding mode control by exploiting the specification of the field oriented control scheme (FOC). The first regulator is used to force the photovoltaic generator to operate at the maximum power point, while the second is used to provide the field oriented control to improve the system performance.The whole system is analysed and its mathematical model is done. Matlab is used to validate the performance and robustness of the proposed control strategy.
Źródło:
Bulletin of the Polish Academy of Sciences. Technical Sciences; 2019, 67, 3; 605-611
0239-7528
Pojawia się w:
Bulletin of the Polish Academy of Sciences. Technical Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Robust impedance control of a piezoelectric stage under thermal and external load disturbances
Autorzy:
Zareinejad, M.
Rezaei, S. M.
Ghidary, S. S.
Abdullah, A.
Motamedi, M.
Powiązania:
https://bibliotekanauki.pl/articles/969687.pdf
Data publikacji:
2009
Wydawca:
Polska Akademia Nauk. Instytut Badań Systemowych PAN
Tematy:
piezoelectric actuator
sliding mode
impedance control
hysteresis
Opis:
Piezoelectric actuators are widely used in micromanipulation tasks such as atomic force microscopy and cell manipulation. However, the hysteresis nonlinearity and the creep reduce their fidelity and cause difficulties in the micromanipulation control procedure. Besides, variation of temperature and external loads could change the model parameters identified for the piezo actuator. In this paper, a novel feedforward-feedback controller is proposed. The modified Prandtl-Ishlinskii model is utilized to linearize the actuator hysteresis in feedforward scheme and a sliding mode based impedance control with perturbation estimation is used to cancel out the thermal and external load disturbances in feedback scheme. The efficiency of the proposed controller is verified by experiments.
Źródło:
Control and Cybernetics; 2009, 38, 3; 635-648
0324-8569
Pojawia się w:
Control and Cybernetics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An investigation of nonlinear tangential contact behaviour of a spherical particle under varying loading
Autorzy:
Zabulionis, D.
Kacianauskas, R.
Markauskas, D.
Rojek, J.
Powiązania:
https://bibliotekanauki.pl/articles/201333.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
discrete element method
tangential elastic-frictional contact
incrementally linear constitutive relationship
stick-sliding switch
Opis:
An analytical and numerical study of the tangential contact of a spherical particle under varying combined normal-tangential loading is presented. The normal and tangential contact is described by the Hertz and regularized Coulomb laws. This study is focused on the analysis of the tangential displacement of the particle’s contact point under variable normal force and reevaluation of the procedures for calculation of the tangential force. The incremental displacement-driven and force-driven constitutive relationships are developed. The importance of an adequate numerical treatment of the tangential component of the contact force is shown for the slide mode, and the recommendations for its evaluation are proposed. The performance of the algorithm is demonstrated by solving the problem of the oblique impact of the spherical particle on the wall. The suggested methodology allows us to analyse the elastic and sliding effects of the tangential interaction more precisely than existing methodologies. Besides, the issue of the direction of the tangential force, when the Coulomb limit is reached, was reconsidered in one-dimensional case by taking three versions of the unit direction vector, which are based on the tangential elastic displacement, tangential stick force, and tangential relative velocity of the contact point of the particle.
Źródło:
Bulletin of the Polish Academy of Sciences. Technical Sciences; 2012, 60, 2; 265-278
0239-7528
Pojawia się w:
Bulletin of the Polish Academy of Sciences. Technical Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Vibration control and performance analysis of full car active suspension system using fractional order terminal sliding mode controller
Autorzy:
Yuvapriya, T.
Lakshami, P.
Rajendiran, S.
Powiązania:
https://bibliotekanauki.pl/articles/230099.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
active suspension system
fractional order terminal sliding mode controller
ISO8608
ISO2631
stability analysis
vibration dose value
Opis:
The main goal of introducing Active Suspension System in vehicles is to reduce the vehicle body motion under road obstacles which improves the ride comfort of the passenger. In this paper, the Full Car Model (FCM) with seven Degrees of Freedom is considered and simulated by MATLAB/Simulink. The Terminal Sliding Mode Controller (TSMC) and Fractional Order Terminal Sliding Mode Controller (FOTSMC) are designed to enhance the ride quality, stability and passenger comfort for FCM. The designed FOTSMC has the ability to provide higher control accuracy in a finite time. The performances of the designed controllers are evaluated by measuring the vehicle body vibration in both angular and vertical direction under bump input and ISO-8608 random input against passive suspension system. The Frequency Weighted Root Mean Square (FWRMS) and Vibration dose value of Body Acceleration as per ISO-2631 are evaluated for FOTSMC, TSMC and PSS. The stability of the FCM is proved by Lyapunouv theory. Further analysis with sprung mass and speed variation of FCM demonstrate the robustness of proposed controller. To investigate the performances of designed controllers, comparison is made with existing Sliding Mode Controller (SMC) which proves that the designed FOTSMC performs better than existing SMC.
Źródło:
Archives of Control Sciences; 2020, 30, 2; 295-324
1230-2384
Pojawia się w:
Archives of Control Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Lqr-Based Nonlinear Tuning Relay Control Design With Fast Convergence
Autorzy:
Yu, X.
Xia, Y.
Ledwich, G.
Oghanna, W.
Powiązania:
https://bibliotekanauki.pl/articles/908299.pdf
Data publikacji:
1999
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
sterowanie rozdzielcze
sterowanie przekaźnikowe
switching control
LQR
relay control
sliding mode
Opis:
In this article, we present a relay control scheme based on LQR design with fast convergence. This scheme provides a practical and simple way to achieve fast convergence based on the well-known LQR design principle. The controller is a global stabiliser in the sense that for any given initial condition, we can always initialize the controller to drive the system to reach the origin. This controller is tunable in accordance with the position of the system state: the closer to the origin, the larger the control gains, which results in a fast control that maintains bounded control magnitude. It has also been shown that setting matrix Q can significantly influence the tendency of eigenvalues to switch the hyperplane. The relation between matrix Q and the tendency of those eigenvalues has been identified. Simulation results are presented to demonstrate the effectiveness of the scheme.
Źródło:
International Journal of Applied Mathematics and Computer Science; 1999, 9, 2; 313-326
1641-876X
2083-8492
Pojawia się w:
International Journal of Applied Mathematics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A fault monitoring method for wind power generation system based on sliding mode observer
Autorzy:
Yu, Wenxin
Huang, Shao Dao
Jiang, Dan
Powiązania:
https://bibliotekanauki.pl/articles/141570.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
double-fed induction generator (DFIG)
sliding model observer (SMO)
stator voltage-oriented
Opis:
In this paper, a rotor current fault monitoring method is proposed based on a sliding mode observer. Firstly, the state-space model of the Double-Fed Induction Generator (DFIG) is constructed by vector transformation. Meanwhile, the stator voltage orientation vector control method is applied to decouple a stator and rotor currents, so as to obtain the correlation between the stator and rotor current. Furthermore, the mathematical model of stator voltage orientation is obtained. Then a state sliding mode observer (SMO) is established for the output current of the rotor of the DFIG. The stability and reachability of the system in a limited time is proved. Finally, the system state is determined by the residuals of the measured and estimated rotor currents. The simulation results show that the method proposed in this paper can effectively monitor the status: a normal state, voltage drop faults, short-circuit faults between windings, and rotor current sensor faults which have the advantages of fast response, high stability.
Źródło:
Archives of Electrical Engineering; 2020, 69, 3; 625-643
1427-4221
2300-2506
Pojawia się w:
Archives of Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
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