Статті в журналах: "Orientation and stabilization subsystem"

1

Peresada, S., S. Bozhko, S. Kovbasa, and Ye Nikonenko. "ROBUST DIRECT FIELD ORIENTED CONTROL OF INDUCTION GENERATOR." Tekhnichna Elektrodynamika 2021, no. 4 (June 17, 2021): 14–24. http://dx.doi.org/10.15407/techned2021.04.014.

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A novel and robust field oriented vector control method for standalone induction generators (IG) is presented. The proposed controller exploits the concept of direct field orientation and provides asymptotic rotor flux modulus and DC-link voltage regulations when a DC-load is constant or slowly varying. Flux subsystem, designed using Lyapunov’s second method, has, in contrast to standard structures, closed loop properties and therefore is robust with respect to rotor resistance variations. A decomposition approach on the base of the two-time scale separation of the voltage and torque current dynamics is used for design of the voltage subsystem. The feedback linearizing voltage controller is designed using a steady state IG power balance equation. The resulting quasi-linear dynamics of the voltage control loop allows use of simple controllers tuning procedure and provides an improved dynamic performance for variable speed and flux operation. Results of a comparative experimental study with standard indirect field oriented control are presented. In contrast to existing solutions, the designed controller provides system performances stabilization when speed and flux are varying. It is experimentally shown that a robust field oriented controller ensures robust flux regulation and robust stabilization of the torque current dynamics leading to improved energy efficiency of the electromechanical conversion process. The proposed controller is suitable for energy generation systems with variable speed operation. References 18, figures 8.

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2

Kuseyri, Sina. "Modelling and stabilization of a three-axis ship-mounted mobile antenna system." Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment 231, no. 2 (August 19, 2016): 533–41. http://dx.doi.org/10.1177/1475090216661908.

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A mobile satellite communication antenna is a device installed on a moving carrier for mobile satellite communication. Gimballed motorized pedestals are used to eliminate the effect of disturbance and maintain uninterrupted communication when the carrier is moving. Mobile satellite communication antennas are becoming increasingly more popular due many advantages of mobile satellite communication. In this paper, a three-axis ship-mounted antenna on a pedestal gimbal system is studied. We study the problem with a different perspective and method from the previous work for two-axis antenna pedestals. The former studies treat the subsystems to be isolated and design controllers separately, which neglect the coupling effects in the dynamics of two or three-axis antenna pedestal gimbals. We treat three sub-systems as a whole and derive the dynamic model of the system using the Newton–Euler method. Based on the dynamic model, linear PI controllers are designed to stabilize the antenna to keep its orientation towards the satellite. The design objective of the control system is to direct the on-board antenna toward a satellite and to keep its orientation unaltered despite the effect of sea waves disturbing the antenna. Simulation results are presented to show the stabilization performance of the system with the synthesized controllers.

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3

Petrusová, Helena, Zdeněk Havlas, Pavel Hobza, and Rudolf Zahradník. "A theoretical study on acetylene dimer, acetylene-s-tetrazine and acetylene-benzene associates." Collection of Czechoslovak Chemical Communications 53, no. 11 (1988): 2495–502. http://dx.doi.org/10.1135/cccc19882495.

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Stabilization energies for the title van der Waals molecules were calculated for various mutual orientations of the subsystems. The interaction energy was expressed as a sum of three contributions: the Hartree-Fock interaction energy, the basis set superposition error and the dispersion energy. The potential energy minima represent reasonably good estimates of the structures of the van der Waals molecules.

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4

NISHIO, Kazunori, Kenji KASHIMA, and Jun-ichi IMURA. "Global Feedback Stabilization of Quantum Noiseless Subsystem." Transactions of the Society of Instrument and Control Engineers 45, no. 9 (2009): 459–68. http://dx.doi.org/10.9746/sicetr.45.459.

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5

Rosinová, D., and V. Veselý. "Decentralized Controller Design: Subsystem Robust Stabilization Approach." IFAC Proceedings Volumes 44, no. 1 (January 2011): 2541–45. http://dx.doi.org/10.3182/20110828-6-it-1002.03150.

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6

Su, Baili, and Dandan Chunyu. "Finite-Time Optimization Stabilization for a Class of Constrained Switched Nonlinear Systems." Mathematical Problems in Engineering 2018 (2018): 1–8. http://dx.doi.org/10.1155/2018/6824803.

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This paper studies the finite-time stability problem of a class of switched nonlinear systems with state constraints and control constrains. For each subsystem, optimization controller is designed by choosing the appropriate Lyapunov function to stabilize the subsystem in finite time and the estimation of the region of attraction can be prescribed. For the whole switched nonlinear system, a suitable switched law is designed to ensure the following: (1) at the time of the transition, Lyapunov function’s value of the switched-in subsystem being less than the value of the last subsystem; (2) the finite-time stability of the whole close-loop system. Finally, a simulation example is used to verify the effectiveness of the proposed algorithm.

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7

Gao, Zilin, Yinhe Wang, and Lili Zhang. "Adaptive control of structural balance for complex dynamical networks based on dynamic coupling of nodes." International Journal of Modern Physics B 32, no. 04 (February 2018): 1850042. http://dx.doi.org/10.1142/s021797921850042x.

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In the existing research results of the complex dynamical networks controlled, the controllers are mainly used to guarantee the synchronization or stabilization of the nodes’ state, and the terms coupled with connection relationships may affect the behaviors of nodes, this obviously ignores the dynamic common behavior of the connection relationships between the nodes. In fact, from the point of view of large-scale system, a complex dynamical network can be regarded to be composed of two time-varying dynamic subsystems, which can be called the nodes subsystem and the connection relationships subsystem, respectively. Similar to the synchronization or stabilization of the nodes subsystem, some characteristic phenomena can be also emerged in the connection relationships subsystem. For example, the structural balance in the social networks and the synaptic facilitation in the biological neural networks. This paper focuses on the structural balance in dynamic complex networks. Generally speaking, the state of the connection relationships subsystem is difficult to be measured accurately in practical applications, and thus it is not easy to implant the controller directly into the connection relationships subsystem. It is noted that the nodes subsystem and the relationships subsystem are mutually coupled, which implies that the state of the connection relationships subsystem can be affected by the controllable state of nodes subsystem. Inspired by this observation, by using the structural balance theory of triad, the controller with the parameter adaptive law is proposed for the nodes subsystem in this paper, which may ensure the connection relationship matrix to approximate a given structural balance matrix in the sense of the uniformly ultimately bounded (UUB). That is, the structural balance may be obtained by employing the controlling state of the nodes subsystem. Finally, the simulations are used to show the validity of the method in this paper.

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8

Rosinova, D., and M. Halická. "Decentralized stabilization of discrete-time systems: subsystem robustness approach." IFAC Proceedings Volumes 27, no. 11 (September 1994): 209–13. http://dx.doi.org/10.1016/s1474-6670(17)47649-x.

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9

Ren, Ru-Yi, Zao-Jian Zou, and Jian-Qin Wang. "Time-Scale Decomposition Techniques Used in the Ship Path-Following Problem with Rudder Roll Stabilization Control." Journal of Marine Science and Engineering 9, no. 9 (September 18, 2021): 1024. http://dx.doi.org/10.3390/jmse9091024.

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The motion control of a surface ship based on a four degrees of freedom (4-DoF) (surge, sway, roll, and yaw) maneuvering motion model is studied in this paper. A time-scale decomposition method is introduced to solve the path-following problem, implementing Rudder Roll Stabilization (RRS) at the same time. The control objectives are to let the ship to track a predefined curve path under environmental disturbances, and to reduce the roll motion at the same time. A singular perturbation method is used to decouple the whole system into two subsystems of different time scales: the slow path-following subsystem and the fast roll reduction subsystem. The coupling effect of the two subsystems is also considered in this framework of analysis. RRS control is only possible when there is the so-called bandwidth separation characteristic in the ship motion system, which requires a large bandwidth separation gap between the two subsystems. To avoid the slow subsystem being affected by the wave disturbances of high frequency and large system uncertainties, the L1 adaptive control is introduced in the slow subsystem, while a Proportion-Differentiation (PD) control law is adopted in the fast roll reduction subsystem. Simulation results show the effectiveness and robustness of the proposed control strategy.

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10

Pang, Hongbo, and Chensong Li. "Incremental passivity and stabilization for switched nonlinear systems." Transactions of the Institute of Measurement and Control 42, no. 11 (April 24, 2020): 2088–102. http://dx.doi.org/10.1177/0142331220905389.

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This paper studies the problems of incremental passivity, incremental passification and incremental stabilization for a switched nonlinear system. First, an incremental passivity concept for switched nonlinear systems is proposed. Each subsystem is only required to be incrementally passive, when it is active. The energy change of each inactive subsystem is charaterized. Then, a sufficient condition for such a system to be incrementally passive is given. Second, a state-dependent switching law and state feedback controllers are designed to render a system with relative degree one incrementally passive. Third, we show that an incrementally passive switched nonlinear system can be incrementally stabilized under some constraints on the energy change of inactive subsystems. In particular, a recursive feedback incremental passification design technique is adopted to achieve the incremental stability for a switched nonlinear system with any same relative degree by designing a set of feedback controllers and a state-dependent switching law, constructively. Finally, two examples are provided to verify the effectiveness of the proposed theory.

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11

Zariņš, Ansis, Diāna Haritonova, Augusts Rubans, Gunārs Silabriedis, and Jānis Zvirgzds. "FIELD TESTS OF ASTROMETRIC SUBSYSTEM." Geodesy and cartography 42, no. 1 (April 8, 2016): 1–6. http://dx.doi.org/10.3846/20296991.2016.1168029.

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The paper presents results of astrometric subsystem’s functionality tests for space object laser ranging and astrometric position determination device, which is under construction in the Institute of Geodesy and Geoinformatics (GGI) of the University of Latvia. Properties of hardware performance for astrometric image acquisition were evaluated and optimal parameters have been selected. Software for image processing and calculation of instrument orientation was tested and adjustments have been made for real-time operation support. Object tracking properties were evaluated, and mount error model parameters were calculated, using test measurements.

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12

Pagilla, Prabhakar R., and Yongliang Zhu. "A Decentralized Output Feedback Controller for a Class of Large-Scale Interconnected Nonlinear Systems." Journal of Dynamic Systems, Measurement, and Control 127, no. 1 (April 25, 2004): 167–72. http://dx.doi.org/10.1115/1.1870047.

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The decentralized output feedback control problem for a class of large-scale interconnected nonlinear systems is considered. The nonlinear interconnection function of each subsystem is assumed to satisfy a quadratic constraint on the entire state of the large-scale system. A decentralized estimated state feedback controller and a decentralized observer are designed for each subsystem. Sufficient conditions, for each subsystem, under which the proposed controller and observer can achieve exponential stabilization of the overall large-scale system are developed. Simulation results on a numerical example are given to verify the proposed design.

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13

Hu, Mingyuan, Kyunghyun Lee, Hyeongki Ahn, Ahyeong Choi, Hyunchang Kim, and Kwanho You. "Stabilization and Tracking of a Quadrotor Using Modified Sigmoid Sliding Mode Control." Sensors 22, no. 10 (May 10, 2022): 3618. http://dx.doi.org/10.3390/s22103618.

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A modified sigmoid sliding mode control (MS-SMC) approach is proposed for stabilizing and tracking a quadrotor system with a nonlinear sliding surface, where the dynamics model is underactuated, highly coupled, and nonlinear. The constructed nonlinear sliding surface is based on the traditional sliding mode surface with a modified sigmoid function, allowing the initial value to quickly reach equilibrium. A new type of nonlinear SMC is applied for performance improvement of the quadrotor using the proposed modified sigmoid sliding surface. To control the quadrotor effectively, a double-loop control method is used to design the control rate, in which the position subsystem is the outer loop, and the attitude subsystem is the inner loop.With the Lyapunov function, the stability of the overall closed-loop system is ensured by stabilizing each subsystem step by step. Moreover, from a practical point of view, the system performance under the model uncertainties and external disturbances are also considered. The simulation results show that the proposed MS-SMC performs better than the conventional sliding mode control (CSMC) and the back-stepping sliding mode control (BS-SMC) in terms of stabilization and tracking against external disturbances.

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14

Yu, Mei, Nan Ding, Wen Tan, and Junyan Yu. "A Switched Approach to Robust Stabilization of Multiple Coupled Networked Control Systems." Abstract and Applied Analysis 2014 (2014): 1–13. http://dx.doi.org/10.1155/2014/623697.

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This paper proposes a switched approach to robust stabilization of a collection of coupled networked controlled systems (NCSs) with node devices acting over a limited communication channel. We suppose that the state information of every subsystem is split into different packets and only one packet of the subsystem can be transmitted at a time. Multiple NCSs with norm-bounded parameter uncertainties and multiple transmissions are modeled as a periodic switched system in this paper. State feedback controllers can be constructed in terms of linear matrix inequalities. A numerical example is given to show that a collection of uncertain NCSs with the problem of limited communication can be effectively stabilized via the designed controller.

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15

Liu, Lizhi, Yinhe Wang, Xiaoxiao Li, and Zilin Gao. "Structural balance for discrete-time complex dynamical network associated with the controlled nodes." Modern Physics Letters B 34, no. 10 (January 10, 2020): 2050098. http://dx.doi.org/10.1142/s0217984920500980.

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In this paper, the discrete-time complex dynamical networks with dynamic weighted value of connection relationships are regarded to be composed of the node and link subsystems, and the state variables of the two subsystems are mutually coupled. Different from most of the existing researches on synchronization or stabilization of nodes, the emphasis of this paper is on the links instead of nodes. This paper mainly focuses on the generation mechanism of structural balance in the link subsystem, the nodes only play an auxiliary role. Associated with the dynamic coupling term in the link subsystem, the suitable controller is proposed for node subsystem such that the structural balance of link subsystem without control input be achieved indirectly. Finally, a numerical simulation is given to show the effectiveness of the method in this paper.

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16

Abas, Norafizah, Rini Akmeliawati, Zulkiflie Ibrahim, M. Zamzuri A. Rashid, and N. Hazahsha Samsudin. "Design of Auto-Stabilization Control Technique for a Quadrotor System." Applied Mechanics and Materials 313-314 (March 2013): 559–64. http://dx.doi.org/10.4028/www.scientific.net/amm.313-314.559.

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This paper presents the design of auto-stabilization control technique for a quadrotor system. Aquadrotor is a highly nonlinear and has to be stabilized by a suitable control technique. Therefore, the main focus of this research is to design an appropriate control algorithm that able to auto-stabilize the quadrotor at hover. The dynamic modeling of the quadrotor is described by sets of equations of motion that are derived based on the Newton-Euler formalism with the implementation of UKF for parameter identification and state estimation. The control strategy adopted includes feedback linearization coupled with Proportional-Derivative (PD) controller for the translational subsystem and backstepping based Proportional-Integral-Derivative (PID) controller for the rotational subsystem. It is developed in MATLAB/Simulink platform and is validated via real-time implementation. Both controllers give satisfactory simulation results, where acceptable peak of overshoot and small steady state errors are achieved. Experimentally, the throttle is controlled in manual mode while attitude angles are stabilized automatically. The simulation and experimental results show that the proposed controller is able to effectively stabillized the quadrotor.

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17

Liu, Chen, Chaoyang Dong, Qing Wang, and Maopeng Ran. "Stabilization of a class of switched uncertain systems by active disturbance rejection control." Transactions of the Institute of Measurement and Control 40, no. 16 (May 30, 2018): 4421–31. http://dx.doi.org/10.1177/0142331217749697.

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The problem of stabilization for a class of switched uncertain non-linear systems is studied by active disturbance rejection control (ADRC). Coordinate transformation is applied to transform the system into a strict feedback system in normal form. The unknown non-linearity, parameter uncertainty and external disturbance are treated as an extended state of each subsystem, and a corresponding switched extended state observer (ESO) is designed. Based on the output of the switched ESO, a switching ADRC law is proposed. Rigorous proof is given to show that the switched ESO can estimate system states and the unknown non-linearity of each subsystem effectively. Furthermore, the proposed controller guarantees the closed-loop system be semi-globally uniformly ultimately bounded for a class of switching with average dwell time. A numerical example illustrates the effectiveness of the proposed method.

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18

Jing, Li, and Li Liu. "The Stabilization of Switched Systems with Input Saturation." Advanced Materials Research 945-949 (June 2014): 2676–79. http://dx.doi.org/10.4028/www.scientific.net/amr.945-949.2676.

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The paper analyzed the stability of switched systems with input saturation. First it considered a special case: the switched system with only one subsystem. Using a new method to dispose saturation in the system, the paper gets the sufficient condition of stability of the system. Based on the result, the controller of the system is designed. Then common switched systems were studied. By convex combination method we obtain the sufficient conditon of stability of switched systems and propose a method to estimate the attration domain of the systems.

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19

Zhu, Yanli, and Yuangong Sun. "Stabilization of Discrete-Time Planar Switched Linear Systems with Impulse." Discrete Dynamics in Nature and Society 2013 (2013): 1–7. http://dx.doi.org/10.1155/2013/134296.

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We study the stabilization problem of discrete-time planar switched linear systems with impulse. When all subsystems are controllable, based on an explicit estimation on the state transition matrix, we establish a sufficient condition such that the switched impulsive system is stabilizable under arbitrary switching signal with given switching frequency. When there exists at least one uncontrollable subsystem, a sufficient condition is also given to guarantee the stabilization of the switched impulsive system under appropriate switching signal.

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20

Zhu, Baolong, Zhiping Zhang, Mingliang Suo, Ying Chen, and Shunli Li. "Sampled-data mixed H∞ and passive control for attitude stabilization and vibration suppression of flexible spacecrafts with input delay." Journal of Vibration and Control 24, no. 22 (January 31, 2018): 5401–17. http://dx.doi.org/10.1177/1077546318754681.

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This paper deals with the problem of mixed [Formula: see text] and passive control for flexible spacecrafts subject to nonuniform sampling and time-varying delay in the input channel. An impulsive observer-based controller is introduced and the resulting closed-loop system is a hybrid system consisting of a continuous time-delay subsystem and an impulsive differential subsystem. As a first result, we derive a generalized bounded real lemma (GBRL), that is, a generalized [Formula: see text] performance criterion, for the impulsive differential subsystem by constructing a time-varying Lyapunov functional. Then, on the basis of this GBRL and utilizing the Lyapunov–Krasovskii approach, a sufficient condition is derived to asymptotically stabilize the closed-loop system and simultaneously guarantee a prescribed mixed [Formula: see text] and passivity performance index. A design method is proposed for the desired controller, which can be readily constructed by solving a convex optimization problem with linear matrix inequalities (LMIs) constraints. Finally, numerical experiments are provided to support the theoretical results, and comparisons with former approaches are also discussed.

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21

HAJT, Sławomir, and Grzegorz STANKIEWICZ. "CHARAKTERISTICS OF THE FUNCTIONAL AND TECHNICAL SOLUTIONS USED IN THE LOGISTIC SUBSYSTEM OF SUPPLYING OF GREAT BRITAIN, THE USA, FRANCE AND GERMANY – PART II." Scientific Journal of the Military University of Land Forces 160, no. 2 (April 1, 2011): 58–76. http://dx.doi.org/10.5604/01.3001.0002.2956.

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In the first part of the article authors introduced selected operational and tactical aspects which are determining the size of material needs contemporary transport technologies of the armies in the contemporary armed struggle. Moreover there was described an overall characteristics of contemporary transport technologies. Furthermore in the context generally identified material needs of the armies in the military peacekeeping and stabilization operations authors introduced functional and technical solutions being used in the American and British supply subsystem of the land forces.Currently presented text in is fully devoted to characteristics of functional and technical solutions applied in the supply subsystem of France and Germany.

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22

Xu, Honglei, Yi Zhang, Jin Yang, Guanglu Zhou, and Louis Caccetta. "Practical exponential set stabilization for switched nonlinear systems with multiple subsystem equilibria." Journal of Global Optimization 65, no. 1 (July 15, 2015): 109–18. http://dx.doi.org/10.1007/s10898-015-0339-7.

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23

Jing, Li, and Li Liu. "The Stabilization of Switched Time-Delay Linear Systems with Input Saturation." Applied Mechanics and Materials 602-605 (August 2014): 2582–85. http://dx.doi.org/10.4028/www.scientific.net/amm.602-605.2582.

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We focused on the stabilization of switched linear systems with time-delay and input saturation. First, the saturation part of each subsystem was dealt with by a new method and the system was transformed into a general switched system. Secondly, we proposed a sufficient condition for system stability based on Multi - Lyapunov Function. The sufficient condition is expressed into LMI and can be solved with MatLab. Further, we designed the system controller.

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24

Leonov, A. I., and P. N. Nikolaev. "Providing Nanosatellite Triaxial Gravitational Orientation Using Magnetic Actuators." IOP Conference Series: Materials Science and Engineering 1215, no. 1 (January 1, 2022): 012005. http://dx.doi.org/10.1088/1757-899x/1215/1/012005.

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Abstract Three-axis gravity stabilization of 3U CubeSat is achieved due to selection of the nanosatellite moments of inertia at the design stage, as well as special modes included in the algorithm to provide stabilization of CubeSat relative to each motion channel separately. In this paper, we propose a modified algorithm based on the magnetic stabilization algorithm B-dot. The modified algorithm provides three modes intended to damp the initial angular velocity to the value of the orbital angular velocity, to keep the angular velocity at a value close to that of the orbital angular velocity, and to provide the nanosatellite gravitational triaxial stabilization by using one magnetic coil located on the axis with the transversal moment of inertia, which is possible due to the small angle between the magnetic field line and the satellite's trajectory. We propose two modifications for forming a control loop for orientation and stabilization of the 3U CubeSat: the first one uses measurements from magnetometers and angular rate sensors as feedback, and the second one, only magnetometers. The efficiency of the two modifications of modifications was studied by means of statistical modeling.

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25

Abramov, Yuriy, Oleksii Basmanov, Valentina Krivtsova, Andrey Mikhayluk, and Oleksandra Mikhayluk. "Developing an algorithm for monitoring gas generators of hydrogen storage and supply systems." EUREKA: Physics and Engineering, no. 2 (March 31, 2022): 45–54. http://dx.doi.org/10.21303/2461-4262.2022.002262.

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In relation to the main element of the hydrogen storage and supply system based on the hydro-reacting composition – the gas generator – an algorithm for its control has been developed. The development of such an algorithm is carried out in three stages. At the first stage, the problem of formalizing the hydrogen generation process is solved. Formalization of this process is carried out using the transfer function of the gas generator. The use of the criterion for the minimum error of the mismatch of the given amplitude-frequency characteristics of the gas generator allows to represent its transfer function in the form of a transfer function of the inertial link. At the second stage, the problem of determining the conditions for the occurrence of self-oscillations in the pressure stabilization subsystem is solved. A prerequisite for the emergence of a self-oscillating mode of operation of the hydrogen storage and supply system is the presence of a relay static characteristic of the pressure sensor. For the characteristic parameters of such a system, the ranges of values of the parameters of self-oscillations, frequencies and amplitudes, are determined. For these parameters, analytical expressions are obtained, which include the main parameters of the pressure stabilization subsystem in the hydrogen storage and supply system. At the third stage, the problem of forming a gas generator control algorithm is solved. As a test action in the implementation of the control algorithm, self-oscillations in the pressure stabilization subsystem are used. The control algorithm for the gas generator of the hydrogen storage and supply system includes determining the parameters of self-oscillations and comparing their values with the values obtained a priori. A typical diagram of a hydrogen storage and supply system is presented, in which the developed gas generator control algorithm is implemented

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26

Shi, Hai Bin, and Li Qi. "Output Feedback Stabilization Based on General Solution of Matrix Equation." Advanced Materials Research 546-547 (July 2012): 903–9. http://dx.doi.org/10.4028/www.scientific.net/amr.546-547.903.

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This paper gives a method for static output feedback stabilization of linear time invariant systems. A general solution of a matrix equation concerning system parameter matrices is used to construct a state coordinate transformation. Then, the closed-loop system is equivalent to a transitional form, whose pivotal isolated subsystem can be stabilized via a gain matrix. This gain matrix is the free variable of the general solution. Furthermore, using this general solution of the matrix equation, the original problem is reformulated to a low dimension system, which can be easily solved. Numerical example is given to illustrate the validity of the proposed algorithm.

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27

De la Sen, Manuel. "On the Stabilization of a Network of a Class of SISO Coupled Hybrid Linear Subsystems via Static Linear Output Feedback." Mathematics 10, no. 7 (March 25, 2022): 1066. http://dx.doi.org/10.3390/math10071066.

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This paper deals with the closed-loop stabilization of a network which consists of a set of coupled hybrid single-input single-output (SISO) subsystems. Each hybrid subsystem involves a continuous-time subsystem together with a digital (or, eventually, discrete-time) one being subject to eventual mutual couplings of dynamics and also to discrete delayed dynamics. The stabilizing controller is static and based on linear output feedback. The controller synthesis method is of algebraic type and based on the use of a linear algebraic system, whose unknown is a vector equivalent form of the controller gain matrix, which is obtained from a previous algebraic problem version which is based on the ad hoc use of the matrix Kronecker product of matrices. As a first step of the stabilization, an extended discrete-time system is built by discretizing the continuous parts of the hybrid system and to unify them together with its digital/discrete-time ones. The stabilization study via static linear output feedback contains several parts as follows: (a) stabilizing controller existence and controller synthesis for a predefined targeted closed-loop dynamics, (b) stabilizing controller existence and its synthesis under necessary and sufficient conditions based on the statement of an ad hoc algebraic matrix equation for this problem, (c) achievement of the stabilization objective under either partial or total decentralized control so that the whole controller has only a partial or null information about couplings between the various subsystems and (d) achievement of the objective under small coupling dynamics between subsystems.

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28

Hatab, Shimaa. "Deepening democracy or stabilization?" Review of Economics and Political Science 4, no. 1 (January 14, 2019): 20–37. http://dx.doi.org/10.1108/reps-10-2018-009.

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Purpose Is the need for stability pre-empting the need for democratic values? How can the EU cope with two contradictory security requirements: the need to promote democratic norms and to secure geostrategic interests? This paper takes on the security-democracy dilemma in a complex way that transcends the realpolitik frame overshadowing the analysis of the EU’s policy orientation in the Southern Mediterranean while considering its normative role as a fig leaf for security interests. Design/methodology/approach This paper investigates the EU’s foreign policy orientation reflected in the ENP in terms of the two logics of action of consequentialism and appropriateness. Tracing changes at the policy level over time between 2011 and 2015, the paper zooms into the implementation of the “new” ENP in the aftermath of the Arab uprisings in Egypt, Libya and Tunisia to highlight additional variation across countries. Findings Building on a document analysis of the official declarations for the policy-making level and of ENP action plans for the implementation level, the paper argues that local political dynamics and the level of the EU’s threat perception shape the EU’s response to the partner countries.

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29

Ngamroo, I. "Design of A Hvdc-Based Controller for Load Change Compensation and Stabilization of Inter-Area Oscillations." ASEAN Journal on Science and Technology for Development 20, no. 3&4 (December 27, 2017): 187–202. http://dx.doi.org/10.29037/ajstd.356.

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As an interconnected power system via a High-Voltage Direct Current (HVDC) link is subjected to a rapid load change with the frequency of inter-area oscillation mode, system frequency and tie line power may be severely disturbed and oscillate. To compensate for the rapid load change and stabilize both frequency and tie line power oscillations due to the inter-area mode, the dynamic power flow control via a HVDC link can be exploited. To implement this concept, a new design method of HVDC-based controller is proposed. To grasp a physical characteristic of the inter-area oscillation frequency, the technique of overlapping decompositions is employed to achieve the subsystem embedded with the inter-area mode. Consequently, the second-order lead/lag controller of HVDC link can be designed in this subsystem. To acquire the desired overshoot of frequency oscillations, the parameters of the controller are automatically optimized by the Tabu Search (TS) algorithm. The effectiveness of the designed controller is investigated in a three-area longitudinal interconnected power system which represents the interconnection between the south of Thailand and Malaysia power systems.

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30

Shigaev, A. S., T. B. Feldman, V. A. Nadtochenko, M. A. Ostrovsky, and V. D. Lakhno. "Investigation of Rhodopsin Chromophore Photoisomerization Based on the Quantum-Classical Model." Mathematical Biology and Bioinformatics 13, no. 1 (May 25, 2018): 169–86. http://dx.doi.org/10.17537/2018.13.169.

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A quantum-classical model of cis-trans photoisomerization of the visual pigment rhodopsin chromophore was investigated in wide ranges of parameters. The quantum subsystem of the model includes three electronic states for rhodopsin: the ground state, the excited state, and the ground state of primary photoproduct. The local temperature of the mass points of the classical subsystem was used as a main reference quantity. The best agreement with experimental data was shown to be in the range of moderate temperatures in agreement with the Raman spectroscopy data. The essential role of a quick transfer of the photoexcitation excess energy into apoprotein part in photoproduct stabilization process was illustrated. Also, the fundamental nature and the local character of the photoreaction were shown in the numerical investigations.

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31

Ischenko, V. I., and I. V. Zimchuk. "A subsystem of the digital correction of control system of space vehicle orientation." Kosmìčna nauka ì tehnologìâ 9, no. 4 (July 30, 2003): 45–48. http://dx.doi.org/10.15407/knit2003.04.045.

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32

Wang, Bin, Chenggao Li, and Weiyu Cao. "Effect of Polyacrylonitrile Precursor Orientation on the Structures and Properties of Thermally Stabilized Carbon Fiber." Materials 14, no. 12 (June 11, 2021): 3237. http://dx.doi.org/10.3390/ma14123237.

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The thermal stabilization process of polyacrylonitrile (PAN) precursor fiber was the key step to prepare high-performance carbon fiber. During the thermal stabilization process, the aggregation structure and the reactivity of molecular chains have significant effects on the microstructures and mechanical properties of carbon fiber. In the present paper, the effects of the orientation structure of PAN precursor fiber on the thermal stabilization reaction and the mechanical properties of carbon fiber were experimentally studied. Using multi-dimensional structural and mechanical properties tests, such as XRD, DSC, 13C NMR and Instron machine testing, the crystalline and skeleton structure, exothermic behavior, and tensile properties of PAN precursor fiber with different orientations in the process of thermal stabilization were characterized to reveal the relationship between microstructure evolution and tensile properties. The results showed that the orientation structure of PAN precursor fiber had an obvious effect on the thermal stabilization process and the tensile stress–strain characteristic. When the heat treatment temperature was lower than 200 °C, the crystallinity and crystallite size of PAN fibers with higher orientation degrees increased significantly. After sufficient thermal stabilization, the original PAN precursor fiber with a higher orientation degree could form more aromatic lamellar structures and showed better regularity. Furthermore, the yield strength and initial modulus of the fibers with a higher orientation degree increased due to the formation of more aromatic rings. The maximum increase in the percentages of yield strength and tensile modulus of the PAN fibers were achieved when the heat-treated temperature was 200 °C, and the percentage values were 138.4% and 158.7% compared to the precursor without heat-treatment. In addition, the elongation at break of the fibers with a higher orientation degree was also relatively larger.

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33

Gao, Fangzheng, Fushun Yuan, Jian Zhang, and Yuqiang Wu. "Further Result on Finite-Time Stabilization of Stochastic Nonholonomic Systems." Abstract and Applied Analysis 2013 (2013): 1–8. http://dx.doi.org/10.1155/2013/439482.

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This paper further investigates the problem of finite-time state feedback stabilization for a class of stochastic nonholonomic systems in chained form. Compared with the existing literature, the stochastic nonholonomic systems under investigation have more uncertainties, such as thex0-subsystem contains stochastic disturbance. This renders the existing finite-time control methods highly difficult to the control problem of the systems or even inapplicable. In this paper, by extending adding a power integrator design method to a stochastic system and by skillfully constructingC2Lyapunov function, a novel switching control strategy is proposed, which renders that the states of closed-loop system are almost surely regulated to zero in a finite time. A simulation example is provided to demonstrate the effectiveness of the theoretical results.

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34

Zhong, Zhixiong, Guanghui Sun, Hamid Reza Karimi, and Jianbin Qiu. "Stability Analysis and Stabilization of T-S Fuzzy Delta Operator Systems with Time-Varying Delay via an Input-Output Approach." Mathematical Problems in Engineering 2013 (2013): 1–14. http://dx.doi.org/10.1155/2013/913234.

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The stability analysis and stabilization of Takagi-Sugeno (T-S) fuzzy delta operator systems with time-varying delay are investigated via an input-output approach. A model transformation method is employed to approximate the time-varying delay. The original system is transformed into a feedback interconnection form which has a forward subsystem with constant delays and a feedback one with uncertainties. By applying the scaled small gain (SSG) theorem to deal with this new system, and based on a Lyapunov Krasovskii functional (LKF) in delta operator domain, less conservative stability analysis and stabilization conditions are obtained. Numerical examples are provided to illustrate the advantages of the proposed method.

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35

Melnik, Maria. "On-board Algorithm for Nanosatellite Orientation and Stabilization System." Procedia Engineering 104 (2015): 57–64. http://dx.doi.org/10.1016/j.proeng.2015.04.097.

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36

杨, 诚笃. "Orientation Optimization Based 3D Video Stabilization for Portable Cameras." Computer Science and Application 05, no. 12 (2015): 436–44. http://dx.doi.org/10.12677/csa.2015.512055.

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37

Sun, Zhiyong, Myoung-Chul Park, Brian D. O. Anderson, and Hyo-Sung Ahn. "Distributed stabilization control of rigid formations with prescribed orientation." Automatica 78 (April 2017): 250–57. http://dx.doi.org/10.1016/j.automatica.2016.12.031.

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38

Hasseni, Seif-El-Islam, and Latifa Abdou. "Robust LPV Control for Attitude Stabilization of a Quadrotor Helicopter under Input Saturations." Advances in Technology Innovation 5, no. 2 (April 1, 2020): 98–111. http://dx.doi.org/10.46604/aiti.2020.3953.

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This article investigates the robust stabilization of the rotational subsystem of a quadrotor against external inputs (disturbances, noises, and parametric uncertainties) by the LFT-based LPV technique. By establishing the LPV attitude model, the LPV robust controller is designed for the system. The weighting functions are computed by Cuckoo Search, a meta-heuristic optimization algorithm. Besides, the input saturations are also taken into account through the Anti-Windup compensation technique. Simulation results show the robustness of the closed-loop system against disturbances, measurement noises, and the parametric uncertainties.

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39

Zhang, Zhe, Toshimitsu Ushio, Jing Zhang, Feng Liu, and Can Ding. "Asymptotic Stabilization for a Class of Linear Fractional-Order Composite Systems." Journal of Advanced Computational Intelligence and Intelligent Informatics 25, no. 3 (May 20, 2021): 285–90. http://dx.doi.org/10.20965/jaciii.2021.p0285.

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In this paper, we present the design for a decentralized control method comprising a series of local state feedback controllers for a class of linear fractional composite systems. In addition, the corresponding asymptotic stabilization criterion is derived. First, we design the local state feedback controllers for each subsystem of the linear fractional composite system. Then, based on the vector Lyapunov function, we combine these local state feedback controllers into a single decentralized controller through which the asymptotic stabilization criterion is proposed for the class of linear fractional composite system. Finally, numerical simulation of a class of linear fractional composite systems is used to verify the accuracy and effectiveness of the decentralized control method.

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40

Xue, Lingrong, Zhen-Guo Liu, Junjun Chen, and Fujing Xu. "Global Robust Stabilization Control for Nonlinear Time-Delay Systems with Dead-Zone Input and Complex Dynamics." Mathematical Problems in Engineering 2020 (May 26, 2020): 1–11. http://dx.doi.org/10.1155/2020/1672595.

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This article investigates the robust stabilization problem for nonlinear time-delay systems with dead-zone input and complex dynamics. By flexibly using the inequality technique, the backstepping control method, and skillfully introducing a new Lyapunov–Krasovskii functional, we obtain a stable controller without using unmeasurable signals in the dynamic subsystem. The control system is guaranteed to be stable finally. Two simulation examples are given to verify the control strategy.

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41

Shahravi, Morteza, and Milad Azimi. "Attitude and Vibration Control of Flexible Spacecraft Using Singular Perturbation Approach." ISRN Aerospace Engineering 2014 (May 29, 2014): 1–13. http://dx.doi.org/10.1155/2014/163870.

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This paper addresses a composite two-time-scale control system for simultaneous three-axis attitude maneuvering and elastic mode stabilization of flexible spacecraft. By choosing an appropriate time coordinates transformation system, the spacecraft dynamics can be divided into double time-scale subsystems using singular perturbation theory (SPT). Attitude and vibration control laws are successively designed by considering a time bandwidths separation between the oscillatory flexible parts motion describing a fast subsystem and rigid body attitude dynamics as a slow subsystem. A nonlinear quaternion feedback control, based on modified sliding mode (MSM), is chosen for attitude control design and a strain rate feedback (SRF) scheme is developed for suppression of vibrational modes. In the attitude control law, the modification to sliding manifold for slow subsystem ensures that the spacecraft follows the shortest possible path to the sliding manifold and highly reduces the switching action. Stability proof of the overall closed-loop system is given via Lyapunov analysis. The proposed design approach is demonstrated to combine excellent performance in the compensation of residual flexible vibrations for the fully nonlinear system under consideration, as well as computational simplicity.

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42

Binazadeh, T., and M.-J. Yazdanpanah. "Robust partial control design for non-linear control systems: a guidance application." Proceedings of the Institution of Mechanical Engineers, Part I: Journal of Systems and Control Engineering 226, no. 2 (September 16, 2011): 233–42. http://dx.doi.org/10.1177/0959651811413013.

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In this paper, a general approach for robust partial stabilization of uncertain non-linear systems is presented. In this approach, the non-linear dynamic system is divided into two subsystems, called the first and the second subsystems. This division is done based on the required stability properties of the system’s states. The reduced input vector (the vector that includes components of the input vector appearing in the first subsystem) is designed to asymptotically stabilize the first subsystem. The proposed scheme is then applied for designing a guidance law as a potential application. Indeed, the paper presents a new approach to the missile guidance problem and shows that asymptotic stability behaviour is not realistic for all states of the guidance system. The effectiveness of the proposed guidance law in interception of manoeuvring targets is demonstrated analytically and through computer simulations.

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43

Denisenko, K. I., V. O. Lesyk, and T. V. Mysak. "INFLUENCE OF THE FILTER IN THE CONTROL CHANNEL CONTOURS OF THE STORAGE CAPACITOR VOLTAGE STABILIZATION ON THE DYNAMICS IN THREE-PHASE SHUNT ACTIVE POWER FILTER." Praci Institutu elektrodinamiki Nacionalanoi akademii nauk Ukraini 2021, no. 58 (May 19, 2021): 55–65. http://dx.doi.org/10.15407/publishing2021.58.055.

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The object of research is a three-phase shunt active power filter, which consists of a semiconductor voltage inverter on fully controllable switches, capacitive storage, and an RL-link. The carried-out decomposition of the research object according to the rate of motion of the dynamic system makes it possible to divide this dynamic system into two subsystems, interconnected by control. The role and influence of the communication subsystem between the voltage stabilization circuit on the storage capacitor of the three-phase shunt active power filter and the circuits for the formation of the compensation current, which is injected by this filter into the distributed power supply network, is considered. The presence of a non-linear load in this network is a source of distortion of the parameters of electrical energy. The formation of the compensation current by the forced introduction of the first order sliding modes along some sliding surfaces was carried out. The two-dimensional sliding surface is a linear combination of the components of the two-dimensional error vectors of the compensation current and the first derivative of the error of this current. The introduced communication subsystem makes it possible to reduce the influence of the disturbance in the form of harmonic components of the rectified voltage on the parameters of the compensating current. The influence of the dynamic characteristics of a communication subsystem with filtering properties on the performance indicators of a parallel active filter and the current distortion factor in the power supply network to which this filter is connected was analyzed. To confirm the theoretical assumptions, a simulation model was built and the results of digital modeling were analyzed. Comparison of different types of filters as a communication subsystem according to the criteria of the duration of the transient process and the harmonic distortion in the current that consumed from the network was carried out. References 26, figures 4, tables 3.

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44

Hayashi, Koichiro, Yasuyoshi Yokokohji, and Tsuneo Yoshikawa. "Tele-Existence Vision System with Image Stabilization for Rescue Robots." Journal of Robotics and Mechatronics 17, no. 2 (April 20, 2005): 181–88. http://dx.doi.org/10.20965/jrm.2005.p0181.

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The purpose of this research is to develop an intuitive interface to control rescue robots. We propose a new image stabilization system for operating rescue robots easily. The use of teleoperated rescue robots is promising in searching for victims in rubble. In the rescue activities with such robots, operators control the robots remotely through images captured by cameras mounted on the robots. Since the orientation of the robots change rapidly while they move in rubble, image stabilization is necessary so the operators can search for victims without suffering from fatigue or motion sickness. However, robot orientation changes so much that conventional image stabilizing methods does not work. In this paper, we propose a new image stabilization system which cancels camera motion caused by such rapid changes of robot orientation on an uneven terrain. After a preliminary experiment, a 3-DOF camera system was designed based on the newly proposed mechanism. To verify the performance of the camera system, we conducted two experiments. The results of the experiments confirmed that the proposed mechanism shows good image stabilization and good tracking of commanded head motion.

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45

Tian, Qinglin, Kevin I.-Kai Wang, and Zoran Salcic. "An INS and UWB Fusion-Based Gyroscope Drift Correction Approach for Indoor Pedestrian Tracking." Sensors 20, no. 16 (August 10, 2020): 4476. http://dx.doi.org/10.3390/s20164476.

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Information fusion combining inertial navigation and radio frequency (RF) technologies, is commonly applied in indoor positioning systems (IPSs) to obtain more accurate tracking results. The performance of the inertial navigation system (INS) subsystem is affected by sensor drift over time and the RF-based subsystem aims to correct the position estimate using a fusion filter. However, the inherent sensor drift is usually not corrected during fusion, which leads to increasingly erroneous estimates over a short period of time. Among the inertial sensor drifts, gyroscope drift has the most significant impact in determining the correct orientation and accurate tracking. A gyroscope drift correction approach is proposed in this study and is incorporated in an INS and ultra-wideband (UWB) fusion IPS where only distance measurements from UWB subsystem are used. The drift correction approach is based on turn detection to account for the fact that gyroscope drift is accumulated during a turn. Practical pedestrian tracking experiments are conducted to demonstrate the accuracy of the drift correction approach. With the gyroscope drift corrected, the fusion IPS is able to provide more accurate tracking performance and achieve up to 64.52% mean position error reduction when compared to the INS only tracking result.

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46

Fu, Xiaodong, Haiping Ai, and Li Chen. "Repetitive Learning Sliding Mode Stabilization Control for a Flexible-Base, Flexible-Link and Flexible-Joint Space Robot Capturing a Satellite." Applied Sciences 11, no. 17 (August 31, 2021): 8077. http://dx.doi.org/10.3390/app11178077.

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During the process of satellite capture by a flexible base–link–joint space robot, the base, joints, and links vibrate easily and also rotate in a disorderly manner owing to the impact torque. To address this problem, a repetitive learning sliding mode stabilization control is proposed to stabilize the system. First, the dynamic models of the fully flexible space robot and the captured satellite are established, respectively, and the impact effect is calculated according to the motion and force transfer relationships. Based on this, a dynamic model of the system after capturing is established. Subsequently, the system is decomposed into slow and fast subsystems using the singular perturbation theory. To ensure that the base attitude and the joints of the slow subsystem reach the desired trajectories, link vibrations are suppressed simultaneously, and a repetitive learning sliding mode controller based on the concept of the virtual force is designed. Moreover, a multilinear optimal controller is proposed for the fast subsystem to suppress the vibration of the base and joints. Two sub-controllers constitute the repetitive learning sliding mode stabilization control for the system. This ensures that the base attitude and joints of the system reach the desired trajectories in a limited time after capturing, obtain better control quality, and suppress the multiple flexible vibrations of the base, links and joints. Finally, the simulation results verify the effectiveness of the designed control strategy.

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47

Espin, M. J., M. A. S. Quintanilla, and J. M. Valverde. "Magnetic stabilization of fluidized beds: Effect of magnetic field orientation." Chemical Engineering Journal 313 (April 2017): 1335–45. http://dx.doi.org/10.1016/j.cej.2016.11.023.

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48

Schermer, J. J., W. J. P. van Enckevort, and L. J. Giling. "Orientation dependent surface stabilization on flame deposited diamond single crystals." Journal of Crystal Growth 148, no. 3 (March 1995): 248–60. http://dx.doi.org/10.1016/0022-0248(94)00958-9.

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49

Padun, O., Y. Kovalenko, B. Rassamakin, V. Ostapchuk, and A. Pynchuk. "DEVELOPING AND CREATION OF GROUND TESTING SIMULATOR FOR ORIENTATION AND STABILIZATION SYSTEM OF POLYITAN NANOSATELLITES." Journal of Rocket-Space Technology 27, no. 4 (December 30, 2019): 125–30. http://dx.doi.org/10.15421/451918.

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The article under the heading "Developing and creation of ground testing simulator for orientation and stabilization system of PolyITAN nanosatellites" is devoted to the research of methods of developing of the specialized simulator for the nanosatellite orientation and stabilization system ground testing. This problem is showed on the example of simulator developed in the National Technical Technical University of Ukraine “Igor Sikorsky Kyiv Polytechnic Institute”. Ground testing of the orientation and stabilization system is critically important phase of the pre-flight preparation of the nanosatellite. In order to provide precise tests, the simulator described in this article was developed. Objective of the simulator is to create targeted magnetic field in assured volume, where flight of the nanosatellite is imitated, stabilization and orientation performances are tested. The introduction describes experience of the PolyITAN team in developing of nanosatellites, the tasks of the first two nanosatellites - PolyITAN-1 and PolyITAN-2 are revealed, the actuality of this research is highlighted. The main part reveals the order of development of the simulator for orientation and stabilization system ground testing in gradual and sector-wise way. First part shows construction decisions in the simulator’s configuration to ensure accomplishment of the simulator’s objective. Second part describes calculation of the number of turns and the diameter of the wire to provide required value of the modulus of the vector of magnetic field induction, which is created by the simulator. Next part is devoted to calculation of power required for power sources, increment of magnetic field induction as a function of the current increment is provided, what is very important for power source selection. Next part is a research of the uniformity sphere - working space of the simulator, which must provide enough volume for testing of the 3U nanosatellites of CubeSat format. Final part describes control system of the simulator.

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50

Zhou, Yiran, Xu Han, Xiaoyuan Hu, Lianghua Xu, and Weiyu Cao. "Evolution of the structural orientation in polyacrylonitrile precursors during stabilization revealed by in-situ synchrotron wide-angle X-ray diffraction and polarized infrared spectroscopy." High Performance Polymers 29, no. 10 (October 6, 2016): 1158–64. http://dx.doi.org/10.1177/0954008316671793.

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Evolution of the orientation structures of polyacrylonitrile (PAN) precursors during thermal stabilization was investigated on the basis of in situ temperature-dependent measurements including synchrotron wide-angle X-ray diffraction and polarized infrared spectroscopy. The results indicated that the Hermans orientation factor of PAN crystallites increased firstly and then decreased in the process of stabilization, while the orientation of molecular chains showed a two-stage decrease. These were mainly attributed to the thermal relaxation of molecular chains and the cyclization reactions, which also resulted in the physical shrinkage as well as the chemical shrinkage apparently observed from the thermal mechanical curves of the precursor.

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