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AFRICON Conference

作者： Jan Vittek Vladimir Vavrus Stephen J. Dodds Roy Perryman Leos Beran Ales Richter Faculty of Electrical Engineering University of Zilina Zilina Slovakia School of Computing and Technology University of East London London UK Institute of Mechatronics Technical University of Liberec Liberec Czech Republic

Design and verification of forced dynamics position control of a drive with a linear permanent magnet synchronous motor is presented. This control method is a relatively new one and using the principles of feedback linearisation offers an accurate realisation of a dynamic speed and position response, which can be selected for a given application by the user. In addition to this, the primary part current vector and the moving part flux vector are maintained mutually perpendicular as in conventional vector control. The control system has the cascade structure with an outer position control loop and an inner speed control loop. To achieve the defined speed response, the derived control law requires estimation of an external force, which is obtained from an observer. The overall control system is verified by simulations and experimentally. Preliminary experimental results confirmed that the moving part position response follows the prescribed one fairly closely.

关键词： Position control Velocity control Synchronous motors Permanent magnet motors Linear feedback control systems Control systems Force control Hysteresis motors Induction motors Acceleration

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A method to study ageing of polydomain ferroelectrics using measurements of nonlinear permittivity

A method to study ageing of polydomain ferroelectrics using ...

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作者： Mokrý, Pavel Institute of Mechatronics and Computer Engineering Technical University of Liberec CZ-46117 Liberec Czech Republic

It is known that the permittivity of the ferroelectric films is affected by several phenomena, which deteriorate the material quality (e.g. the redistribution of the crystal lattice defects, appearance of the electrode-adjacent non-ferroelectric layers or the spontaneous polarization screening due to a free charge injection across the electrode-adjacent layer, etc.). It is also known that the permittivity of ferroelectric polydomain films is controlled by the sum of two contributions: the crystal lattice (intrinsic) contribution and the domain wall movement (extrinsic) contribution. It is the latter one, which is very sensitive to the aforementioned phenomena and which plays a key role in the deterioration of the dielectric response of the ferroelectric polydomain films. In this Article, there is presented a method for the identification of the process, which is responsible for the ferroelectric ageing. The method is based on the analysis of the evolution of both the linear and nonlinear permittivity during ageing. Applicability of the method is theoretically demonstrated on four ageing scenarios in two qualitatively different systems where the evolution of the nonlinear permittivity is controlled, first, by a redistribution of the pinning centers on the domain wall and, second, by microstructural changes at the interface between the ferroelectric layer and the electrode. It is shown that each ageing scenario is characterized by unique trend in the evolution between the linear and nonlinear part of the permittivity, which can be verified experimentally.

关键词： Permittivity

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Polytopic model reconstruction of a pneumatic positioning system

Polytopic model reconstruction of a pneumatic positioning sy...

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International Symposium on Applied Computational Intelligence and Informatics ( SACI)

作者： Patricia Grof Zoltan Petres Janos Gyeviki Department of Mechatronics Optics and Information Engineering Budapest University슠of슠Technology슠and슠Economics Budapest Hungary Cognitive Informatics Group Hungarian Academy of Sciences Computer and Automation Research Institute Budapest Hungary Department of Technical and Process Engineering University of Szeged Szeged Hungary

The main contribution of this paper to develop a mathematical model which describes the movement of a piston of pneumatic cylinder controlled by a proportional valve, keeping the non linear behavior of pneumatic system. The linear parameter varying (LPV) representations and linear matrix inequality (LMI) based analysis and system control design are in the focus of modern control theories.

关键词： Sliding mode control Engine cylinders Robust control Vectors Control systems Mathematical model Pistons Automatic control Valves Pneumatic systems

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On solution of total least squares problems with multiple right-hand sides

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PAMM 2009年第1期8卷

作者： Iveta Hnětynková Martin Plešinger Zdeněk Strakoš Charles University in Prague Faculty of Mathematics and Physics Sokolovská 83 186 75 Prague 8 Czech Republic Institute of Computer Science Academy of Sciences of the Czech Republic Technical University of Liberec Faculty of Mechatronics and Interdisciplinary Engineering Studies Czech Republic

Consider a linear approximation problem AX ≈ B with multiple right–hand sides. When errors in the data are confirmed both to B and A , the total least squares (TLS) concept is used to solve this problem. Contrary to the standard least squares approximation problem, a solution of the TLS problem may not exist. For a single (vector) right–hand side, the classical theory has been developed by G.H. Golub, C.F. Van Loan [2], and S. Van Huffel, J. Vandewalle [4], and then complemented recently by the core problem approach of C.C. Paige, Z. Strakoš [5,6,7]. Analysis of the problem with multiple right–hand sides is still under development. In this short contribution we present conditions for the existence of a TLS solution. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

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The measurement on the solar cells in liberec city

The measurement on the solar cells in Liberec city

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International (EPE-PEMC) Power Electronics and Motion Control Conference

作者： Jiri Kubin Institute of Mechatronics and Computer Engineering Technical University of Liberec Liberec Czech Republic

In the years 2005 - 2007 was realised the project "Pilot project of the power-produsing yield of the solar photovoltaic system in our climatic conditions for requirement of the supplying of the information and monitoring system of liberec cityrdquo. The project was solved at technical university of liberec (TUL) with the cooperation of High School for Electrotechnics and Mechanical engineering in liberec (SPSSE). The project was financed by statutory city of liberec. The paper deals with realisation of the project, measurements proceeding and some particular results.

关键词： Photovoltaic cells Current measurement Meteorology Employment Solar energy Photovoltaic systems Voltage measurement

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Advanced Modelling and Control using a Laboratory Plant with Hybrid Processes

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IFAC Proceedings Volumes 2008年第2期41卷 14636-14641页

作者： J. Hlava B. Šulc Technical University Liberec Faculty of Mechatronics 461 17 Liberec Hálkova 4 Czech Republic Institute of Instrumentation and Control Engineering 166 07 Praha 6 Technická 4 Czech Republic

Advanced control theory is usually associated with the use of abstract mathematical tools. It requires much time and a good theoretical background to understand and explain these tools. In ordinary university courses or in continuing professional education organized by employers, it is not easy to meet these requirements. Widely used system simulation and virtual experiments can be a good aid to increase clarity, but they cannot fully demonstrate the problems that a control designer or user may encounter in practical implementation. A laboratory scale plant has been designed for this purpose in the framework of research activities focused on hybrid systems. It exhibits most of the hybrid phenomena typical of process control applications. The plant is also equipped with industrial control hardware, so that educational (as well as research) experiments can be carried out implementing advanced hybrid control algorithms in conditions close to real world applications. The instrumentation provides a remote web access facility. A mathematical and technical description of the pilot plant is included here, and this will enable readers to consider whether a similar device could be useful for their own educational and/or research purposes. Some examples of experimental results are also given.

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Editorial introduction for the special issue on sensors for microfluidic analysis systems

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IEEE Sensors Journal 2008年第5期8卷 427-429页

作者： Nagle, H. Troy Fair, Richard B. Shannon, Mark A. Tan, Ooi Kiang Geschke, Oliver Ahn, Chong H. Kaynak, Okyay Vellekoop, Michael J. Duke University Department of Electrical and Computer Engineering Durham NC 27708 United States University of Illinois at Urbana-Champaign Department of Mechanical Engineering Urbana IL 61801-2906 United States Nanyang Technological University Division of Microelectronics School of Electrical and Electronic Engineering Singapore 639798 Singapore Technical University of Denmark Department of Micro- and Nanotechnology Kongens Lyngby DK-2800 Denmark University of Cincinnati Department of Electrical and Computer Engineering and Computer Science Cincinnati OH 45221-0030 United States Bogazici University Department of Electrical and Electronics Engineering Istanbul 34342 Turkey Vienna University of Technology Institute of Sensor and Actuator Systems Vienna A-1040 Austria Department of Electrical and Computer Engineering Duke University Electrochemical Society Department of Mechanical Engineering University of Illinois at Urbana-Champaign Urbana IL United States National Science Foundation Science and Technology Center WaterCAMPWS Micro-Nano-Mechanical Systems Laboratory Nanyang Technological University School of Electrical and Electronic Engineering Department of Electrical and Computer Engineering and Computer Science University of Cincinnati Cincinnati OH United States Departments of Electrical Engineering and Biomedical Engineering Microsystems and BioMEMS Laboratory Univensity of Cincinnati Departments of Electrical and Electronics Engineering Bogazici University Istanbul Turkey UNESCO Mechatronics Research and Annlication Centre Vienna Austria Department of Industrial Sensor Systems Institute of Sensor and Actuator Systems Vienna University of Technology Vienna Austria

No abstract available

关键词： Special issues and sections Sensor systems Microfluidics Microelectronics USA Councils Mechanical engineering Actuators Fabrication Biosensors Ferroelectric materials

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Study of the evolution of 180 domain pattern micro structure using measurements of nonlinear permittivity

Study of the evolution of 180 domain pattern micro structure...

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2007 16th IEEE International Symposium on the Applications of Ferroelectrics, ISAF

作者： Mokrý, Pavel Wang, Yongli Tagantsev, Alexander K. Stolichnov, Igor Institute of Mechatronics and Computer Engineering Technical University of Liberec CZ-46117 Liberec Czech Republic Ceramics Laboratory EPFL-Swiss Federal Institute of Technology Lausanne 1015 Switzerland

ISBN: (纸本)1424413338

In this work, we study theoretically and experimentally the linear and nonlinear dielectric response in a system where the extrinsic permittivity is controlled by bending movements of pinned 180 domain walls. We calculated the linear and nonlinear extrinsic contribution to permittivity and discovered a quadratic relationship between them, which is a feature quite different from that of the lattice contribution derived from Landau theory. We show that, from measured values of linear and nonlinear permittivity, it is possible to determine the configuration of the 180 domain pattern and the concentration of the pinning centers in the ferroelectric. Therefore, our results can be used as a simple and useful tool for getting a deeper insight into the configuration of the domain pattern and the quality of the ferroelectric thin films, which is demonstrated on data obtained from [111] oriented PZT (45/55) thin film.

关键词： Permittivity

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On the vibration control using a piezoelectric actuator and a negative capacitor adjusted by a microprocessor

On the vibration control using a piezoelectric actuator and ...

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IEEE International Symposium on Applications of Ferroelectrics (ISAF)

作者： Pavel Mokry Milos Kodejska Tomas Sluka Institute of Mechatronics and Computer Engineering Technical University of Liberec Liberec Czech Republic

The design and realization of an adaptive vibration isolation system based on a method to control the effective elastic stiffness of piezoelectric materials are presented in this paper. In this system, the vibration isolation effect is achieved by absorption of vibrations transmitted through a multi-stack piezoelectric actuator connected to an active analog circuit that behaves as a negative capacitor. The problem of a high sensitivity of the system to the proper adjustment of the negative capacitor and a deterioration of the vibration isolation efficiency in changing operational conditions are analyzed. A method for the self-adjustment of the system by appending an additional digital control circuit to the negative capacitor is implemented. The transmissibility of vibrations through the piezoelectric actuator was measured in different control regimes.

关键词： Vibration control Piezoelectric actuators Capacitors Microprocessors Vibration measurement Adaptive systems Programmable control Adaptive control Control systems Piezoelectric materials

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Study of the evolution of 180° domain pattern microstructure using measurements of nonlinear permittivity

Study of the evolution of 180° domain pattern microstructur...

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IEEE International Symposium on Applications of Ferroelectrics (ISAF)

作者： Pavel Mokry Yongli Wang Alexander K. Tagantsev Igor Stolichnov Institute of Mechatronics and Computer Engineering Technical University of Liberec Liberec Czech Republic Ceramics Laboratory EPFL-Swiss Federal Institute of Technology Lausanne Lausanne Switzerland

In this work, we study theoretically and experimentally the linear and nonlinear dielectric response in a system where the extrinsic permittivity is controlled by bending movements of pinned 180deg domain walls. We calculated the linear and nonlinear extrinsic contribution to permittivity and discovered a quadratic relationship between them, which is a feature quite different from that of the lattice contribution derived from Landau theory. We show that, from measured values of linear and nonlinear permittivity, it is possible to determine the configuration of the 180deg domain pattern and the concentration of the pinning centers in the ferroelectric. Therefore, our results can be used as a simple and useful tool for getting a deeper insight into the configuration of the domain pattern and the quality of the ferroelectric thin films, which is demonstrated on data obtained from [111] oriented PZT (45/55) thin film.

关键词： Microstructure Permittivity measurement Ferroelectric materials Lattices Transistors Ferroelectric films Polarization Dielectric thin films mechatronics Ceramics

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