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- Keyword
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- HF radar (4)
- HFSWR (3)
- Adaptive control (2)
- Artificial neural network (2)
- Chaos (2)
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- High Frequency Surface Wave Radar (2)
- Induction machine (2)
- Nonlinear systems (2)
- OTH radar (2)
- Particle swarm optimization (2)
- Privacy (2)
- RCS (2)
- Radar (2)
- State estimation (2)
- Tracking (2)
- AIA (1)
- ANFIS (1)
- AR model (1)
- Accuracy enhancement (1)
- Accuracy. (1)
- Active appearance (1)
- Actuator design (1)
- Adaptive neuro-fuzzy inference system (1)
- Adaptive systems (1)
- Alignment (1)
- All-pass filter (1)
- Analyzer; data acquisition; harmonics; microcontroller; PQ monitoring; MSP; power quality. (1)
- Anonymity; Wireless Sensor Networks; Data Privacy. (1)
- Ant colony optimization (1)
- Autonomous (1)
Articles 1 - 30 of 75
Full-Text Articles in Physical Sciences and Mathematics
Hierarchical Fuzzy Controller Applied To Multi-Input Power System Stabilizer, Ebrahim Rasooli Anarmarzi, Mohammad Reza Feyzi, Mehrdad Tarafdar Hagh
Hierarchical Fuzzy Controller Applied To Multi-Input Power System Stabilizer, Ebrahim Rasooli Anarmarzi, Mohammad Reza Feyzi, Mehrdad Tarafdar Hagh
Turkish Journal of Electrical Engineering and Computer Sciences
This paper proposes the application of a hierarchical fuzzy system (HFS) based on multi-input power system stabilizer (MPSS) in multi-machine environment. The number of rules increases exponentially with the number of variables in a standard fuzzy system. This problem is solved in the proposed HFS method. In this method, the total number of rules increases only linearly with the number of input variables. HFS consists of a number of low-dimensional fuzzy systems in a hierarchical form. In the MPSS, the deviation of reactive power \Delta Q is added to a \Delta P+ \Delta \omega input type Power System Stabilizer (PSS) …
An Rfid Based Indoor Tracking Method For Navigating Visually Impaired People, Ruşen Öktem, Eli̇f Aydin
An Rfid Based Indoor Tracking Method For Navigating Visually Impaired People, Ruşen Öktem, Eli̇f Aydin
Turkish Journal of Electrical Engineering and Computer Sciences
This paper tackles the RFID based tracking problem in an obscured indoor environment. The proposed solution is an integral part of a navigation aid for guiding visually impaired people in a store. It uses RF signal strengths and is based on the Bayes Decision Theory. An observation vector is formed by received radio signal strength indication values, transmitted from three transmitters at distinct frequencies in the UHF band. The indoor area is divided into square grids, where each grid is considered as a class. The problem of tracking is expressed as classifying the observed radio signal strengths to the most …
K-Anonymity Based Framework For Privacy Preserving Data Collection In Wireless Sensor Networks, Hayretdi̇n Bahşi̇, Albert Levi̇
K-Anonymity Based Framework For Privacy Preserving Data Collection In Wireless Sensor Networks, Hayretdi̇n Bahşi̇, Albert Levi̇
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper, k-anonymity notion is adopted to be used in wireless sensor networks (WSN) as a security framework with two levels of privacy. A base level of privacy is provided for the data shared with semi-trusted sink and a deeper level of privacy is provided against eavesdroppers. In the proposed method, some portions of data are encrypted and the rest is generalized. Generalization shortens the size of the data transmitted in the network causing energy saving at the cost of information loss. On the other hand, encryption provides anonymization with no information loss and without saving energy. Thus, there …
A Power Quality Monitoring System Based On Matlab Server Pages, Bülent Vural, Ali̇ Kizil, Mehmet Uzunoğlu
A Power Quality Monitoring System Based On Matlab Server Pages, Bülent Vural, Ali̇ Kizil, Mehmet Uzunoğlu
Turkish Journal of Electrical Engineering and Computer Sciences
The power quality (PQ) requirement is one of the most important issues for power companies and their customers. Continuously monitoring the PQ from remote and distributed centers will help to improve the PQ. In this study, a remote power quality monitoring system for low voltage sub-networks is developed using MATLAB Server Pages (MSP). MATLAB Server Pages, which is an open source technical web programming language, combines MATLAB with integrated J2EE specifications. The proposed PQ monitoring system uses the MATLAB HTML tag library and the data captured by the DAQ hardware to evaluate the Power Quality parameters. The proposed system can …
Nonlinear Dynamic Analysis Of Mitral Valve Doppler Signals: Surrogate Data Analysis, Esma Uzunhi̇sarcikli
Nonlinear Dynamic Analysis Of Mitral Valve Doppler Signals: Surrogate Data Analysis, Esma Uzunhi̇sarcikli
Turkish Journal of Electrical Engineering and Computer Sciences
In our study, the nonlinear dynamics of mitral valve Doppler signals from 32 healthy and 28 patients with mitral valve stenosis was evaluated using by the computation of Lyapunov exponents, correlation dimension values and surrogate data analysis. Two chaotic features are compared for healthy and patient subjects. It was found that the largest Lyapunov exponent and correlation dimension values derived from patient subjects were larger than that of healthy subjects (\rho < 0.005). Surrogate data analysis was performed to determine the chaotic dynamics of Doppler signals. It was observed that the original and surrogate data have similar spectral features. Receiver operating characteristic (ROC) curves were used to evaluate the nonlinearity character Area Under the curve (AUC) values were obtained as 0.99 and 0.978 for the largest Lyapunov exponent and correlation dimension values, respectively. According to these results, Doppler signals have a nonlinear dynamic property and the largest Lyapunov exponent. Correlation dimension features can be used to detect the change in blood flow velocity of patients with mitral valve stenosis.
Experimental Studies Of A Scaled-Down Tsr-Based Svc And Tcr-Based Svc Prototype For Voltage Regulation And Compensation, Ayetül Gelen, Tankut Yalçinöz
Experimental Studies Of A Scaled-Down Tsr-Based Svc And Tcr-Based Svc Prototype For Voltage Regulation And Compensation, Ayetül Gelen, Tankut Yalçinöz
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper, prototypes of two shunt flexible AC transmission system (FACTS) devices, a thyristor switched reactor (TSR)-based static VAr compensator (SVC) and a thyristor controlled reactor (TCR)-based static VAr compensator- have been developed. The design and testing of both a TSR-based SVC and a TCR-based SVC are accomplished in the Power Systems Research Laboratory of Nigde University. The TSR-based SVC and TCR-based SVC devices are studied in three-bus and single machine infinite bus systems for three-phase static load conditions. The effects of TSR-based SVC and TCR-based SVC devices on load voltages are also analyzed. Experimental results show that significant …
The Effect Of The Channel Reliability Factor In The Map Algorithm On Turbo Code Performance In Bluetooth Systems, Sali̇m Kahveci̇, İsmai̇l Kaya
The Effect Of The Channel Reliability Factor In The Map Algorithm On Turbo Code Performance In Bluetooth Systems, Sali̇m Kahveci̇, İsmai̇l Kaya
Turkish Journal of Electrical Engineering and Computer Sciences
The effects of the channel reliability factor on the performance of turbo decoders that use a maximum a posteriori probability algorithm are investigated for wireless communication fading channels, such as Bluetooth systems. The channel reliability factor is related to the channel signal-to-noise ratio. For various values of the channel reliability factor, the obtained performance curves of the maximum a posteriori probability algorithm are given for the case of DMx Bluetooth data packets. When the channel reliability factor increases, the bit-error-rate performance of the DMx Bluetooth data packets also increases over fading channels.
Remote Sensing Applications Of Hf Skywave Radar: The Australian Experience, Stuart Anderson
Remote Sensing Applications Of Hf Skywave Radar: The Australian Experience, Stuart Anderson
Turkish Journal of Electrical Engineering and Computer Sciences
Australia has conducted research into over-the-horizon radar (OTHR) for almost sixty years. Early programs focused exclusively on military capabilities, such as the detection of aircraft, missiles and ships, but in 1974 a team was formed to design a new OTHR for which a remote sensing mission was proposed. Oceanic wind mapping experiments in 1977-78 yielded promising results so remote sensing became a recognised mission assigned to the new radar, known as Jindalee Stage B. This capability was progressively expanded over the period 1982-87 to include mapping of wave height and other oceanographic variables. A real-time data link to the Australian …
Dual-Use Of Compact Hf Radars For The Detection Of Mid- And Large-Size Vessels, Hugh Roarty, Don Barrick, Josh Kohut, Scott Glenn
Dual-Use Of Compact Hf Radars For The Detection Of Mid- And Large-Size Vessels, Hugh Roarty, Don Barrick, Josh Kohut, Scott Glenn
Turkish Journal of Electrical Engineering and Computer Sciences
This paper describes the development of the SeaSonde High Frequency Radar system into a dual-use application for the mapping of ocean surface currents and detection of ships at sea. This development entailed the creation of a new radar waveform that would permit this dual-use as well as a detection algorithm to identify the ships in the radar spectra. The detection algorithm utilizes two methods for calculating a background signal level: an infinite impulse response (IIR) filter and a two-dimensional median filter. These two methods are employed simultaneously with multiple length averaging times to maximize the number of detections. The initial …
Modeling And Simulation Strategies In High Frequency Surface Wave Radars, Levent Sevgi̇
Modeling And Simulation Strategies In High Frequency Surface Wave Radars, Levent Sevgi̇
Turkish Journal of Electrical Engineering and Computer Sciences
Surface Wave High Frequency Radars (SWHFR) are taken into account in the content of modeling and simulation challenges. Examples related to multi-mixed path surface wave propagation, radar cross section (RCS) prediction, and total radar echo showing target, clutter, noise, and interference are presented.
A Review Of High Frequency Surface Wave Radar For Detection And Tracking Of Ships, Tony Ponsford, Jian Wang
A Review Of High Frequency Surface Wave Radar For Detection And Tracking Of Ships, Tony Ponsford, Jian Wang
Turkish Journal of Electrical Engineering and Computer Sciences
In today's resource-driven economy, maritime nations are claiming economic borders that extend beyond the continental shelf or the 200 nautical mile (nm) Exclusive Economic Zone (EEZ). However, claiming such large economic area places responsibilities on the parent nation to exercise jurisdiction through surveillance and enforcement. The requirement to see beyond the horizon has long been a goal of maritime security forces. Today, this is largely dependent on cooperative vessels voluntarily communicating their intentions to local shore-side authorities, as well as on those vessel sightings reported by patrollers. Recent advances in technology provide maritime nations with options to provide more systematic …
Implementation Of Method For Operating Multiple High Frequency Surface Wave Radars On A Common Carrier Frequency, Ryan Riddolls
Implementation Of Method For Operating Multiple High Frequency Surface Wave Radars On A Common Carrier Frequency, Ryan Riddolls
Turkish Journal of Electrical Engineering and Computer Sciences
The increasing use of High Frequency Surface Wave Radar (HFSWR) for the surveillance of coastal regions is faced with the problem of limited channel availability in the electromagnetic spectrum. Thus, there is a need for multiple radars to share a common frequency channel. Proof-of-concept work is presented here for a method to operate multiple radar systems on a common carrier frequency. A review is provided of an existing concept where a common waveform is modulated by tones varying by a few hertz across the different radars. The signals from the different radars are separated by either pulse-domain filtering or Doppler …
Radar Cross-Section (Rcs) Analysis Of High Frequency Surface Wave Radar Targets, Gonca Çakir, Levent Sevgi̇
Radar Cross-Section (Rcs) Analysis Of High Frequency Surface Wave Radar Targets, Gonca Çakir, Levent Sevgi̇
Turkish Journal of Electrical Engineering and Computer Sciences
Realistic high frequency surface wave radar (HFSWR) targets are investigated numerically in terms of electromagnetic wave -- target interactions. Radar cross sections (RCS) of these targets are simulated via both the finite-difference time-domain (FDTD) method and the Method of Moments (MoM). The virtual RCS prediction tool that was introduced in previous work is used for these investigations. The virtual tool automatically creates the discrete FDTD model of the target under investigation and performs the FDTD RCS analysis. It also automatically constructs a MoM wire grid model of the target; therefore, it is also possible to compare FDTD results against the …
Propagation Modeling And Path Loss Prediction Tools For High Frequency Surface Wave Radars, Gökhan Apaydin, Levent Sevgi̇
Propagation Modeling And Path Loss Prediction Tools For High Frequency Surface Wave Radars, Gökhan Apaydin, Levent Sevgi̇
Turkish Journal of Electrical Engineering and Computer Sciences
Propagation modeling and simulation approaches for the use of High Frequency Surface Wave Radar (HFSWR) are discussed. HFSWR uses vertically polarized surface waves along multi-mixed paths in the lower HF band (3 MHz - 15 MHz). Various numerical propagators are reviewed with an early analytical model. Split Step Fast Fourier Transformation, finite- difference, and finite-element solutions of the well-known one-way, forward propagation Parabolic Equation (PE) model are presented. MATLAB-based numerical propagation prediction tools based on these models are listed. Tests and comparisons among these analytical and numerical tools are given for some canonical surface wave propagation scenarios. The Millington effect …
Antenna Systems With Beam Forming And Beam Steering Capabilities For Hf Skywave Radars, Çağatay Uluişik
Antenna Systems With Beam Forming And Beam Steering Capabilities For Hf Skywave Radars, Çağatay Uluişik
Turkish Journal of Electrical Engineering and Computer Sciences
Radiation characteristics of linearly phased, periodic, planar dipole arrays, which can be used as transmitting/receiving antenna systems for HF skywave radars, are investigated. Rectangular, triangular and trapezoidal arrays are proposed in obtaining different beam shapes in the desired directions. Beam steering is achieved by adjusting the inter-element phase increments coherently. The effects of vertical array-tilt with a desired take-off angle (TOA) \alpha are presented by a number of radiation pattern examples. The ground effect is investigated using the image theory by assuming the Earth's surface as perfectly electric conductor (PEC). Radiated fields are obtained using Floquet wave representations plus the …
Washout Filter Based Control For The Hodgkin-Huxley Nerve Cell Dynamics, Reşat Özgür Doruk
Washout Filter Based Control For The Hodgkin-Huxley Nerve Cell Dynamics, Reşat Özgür Doruk
Turkish Journal of Electrical Engineering and Computer Sciences
In this work we present a washout filter based control approach for stabilizing the oscillations in Hodgkin-Huxley type neurons. The oscillations occur due to the bifurcations that arise from the potassium and sodium channel conductance deviations. The MATCONT toolbox software environment was used for analysis of the bifurcation points in conjunction with MATLAB. The simulations of the Hodgkin-Huxley (HH) model at those points are provided to validate the results obtained from the MATCONT software. Then a washout filter is proposed to stabilize the oscillations occur at the Hopf bifurcation points where the external current injection is used to provide the …
A Robust Method For State Estimation Of Power System With Upfc, Mehrdad Tarafdar Hagh, Mehdi Ahmadi Jirdehi
A Robust Method For State Estimation Of Power System With Upfc, Mehrdad Tarafdar Hagh, Mehdi Ahmadi Jirdehi
Turkish Journal of Electrical Engineering and Computer Sciences
This paper presents a Least Absolute Value (LAV) state estimator for power system using a new method called Recursive Least Squares (RLS). Also, a suitable model is used for state estimation of power system that includes a Unified Power Flow Controller (UPFC). The IEEE 14-bus test system is used to show the validity of the proposed algorithm in estimation of power system states as well as the states of controllable parameters of UPFC.
A Small Scale Education Experiment Kit With Wind Generator-Pem Electrolyser System And Modelling, Özcan Atlam
A Small Scale Education Experiment Kit With Wind Generator-Pem Electrolyser System And Modelling, Özcan Atlam
Turkish Journal of Electrical Engineering and Computer Sciences
A small scale experiment wind energy kit is prepared in order to introduce renewable energy applications. The kit consists of a wind turbine with horizontal axis, a direct current (dc) motor as generator and variable wind excitation system. Performance characteristics of the wind system are defined for different wind speeds. It is found that at the highest 10 m/s wind excitation, the maximum turbine mechanical power from wind is about 0.30 W at 5.3 V., maximum output power of the generator is about 0.18 W and maximum electrical efficiency is about 7% at 4.27 V., wind turbine power coefficients C_p …
Corrective Action Planning Considering Facts Allocation And Optimal Load Shedding Using Bacterial Foraging Oriented By Particle Swarm Optimization Algorithm, Rahmat Allah Hooshmand, Mostafa Ezatabadi
Corrective Action Planning Considering Facts Allocation And Optimal Load Shedding Using Bacterial Foraging Oriented By Particle Swarm Optimization Algorithm, Rahmat Allah Hooshmand, Mostafa Ezatabadi
Turkish Journal of Electrical Engineering and Computer Sciences
Reactive power planning (RPP) involves optimal allocation and determination of the type and size of new reactive power (VAR) supplies to satisfy voltage constraints during normal and contingency states. The RPP issue is in fact an optimization of large scale mixed integer nonlinear programming problem, so it is proper to use an evolutionary algorithm to solve the problem. In this paper, in order to solve the RPP problem for corrective action of power systems, the bacterial foraging (BF) oriented by particle swarm optimization (PSO) algorithm (BF-PSO) is proposed. In the algorithm, the VAR control has been carried out by using …
The Analysis Of A Semiconductor Single Asymmetric And Symmetric Step-Index Laser For Even And Odd Fields By Alpha Method, Mustafa Temi̇z, Mehmet Ünal
The Analysis Of A Semiconductor Single Asymmetric And Symmetric Step-Index Laser For Even And Odd Fields By Alpha Method, Mustafa Temi̇z, Mehmet Ünal
Turkish Journal of Electrical Engineering and Computer Sciences
In this work, semiconductor step-index single waveguide has been analyzed by Alpha Method. A requested quantity of wave guide can be obtained in terms of normalized propagation constant, which is represented by alpha belonging to active region. Based on this method, structural properties of the material containing any requested quantity of the waveguide is theoretically calculated, when the width of the active region, the refractive indices of the regions and the wavelength are given. In the TE mode some important parameters, such as the propagation constants for regions of the semiconductor step-index single waveguide, the wave numbers, the effective index …
Active Illumination And Appearance Model For Face Alignment, Muhi̇tti̇n Gökmen, Fati̇h Kahraman, Sune Darkner, Rasmus Larsen
Active Illumination And Appearance Model For Face Alignment, Muhi̇tti̇n Gökmen, Fati̇h Kahraman, Sune Darkner, Rasmus Larsen
Turkish Journal of Electrical Engineering and Computer Sciences
Illumination conditions have an explicit effect on the performance of face recognition systems. In particular, varying the illumination upon the face imposes such complex effects that the identification often fails to provide a stable performance level. In this paper, we propose an approach integrating face identity and illumination models in order to reach acceptable and stable face recognition rates. For this purpose, Active Appearance Model (AAM) and illumination model of faces are combined in order to obtain an illumination invariant face localization. The proposed method is an integrated Active Illumination and Appearance Model (AIA) which combines identity, illumination and shape …
Robust Feedback Design For Nonlinear Systems: A Survey, Alberto Isidori
Robust Feedback Design For Nonlinear Systems: A Survey, Alberto Isidori
Turkish Journal of Electrical Engineering and Computer Sciences
No abstract provided.
Fractional Order Sliding Mode Control With Reaching Law Approach, Mehmet Önder Efe
Fractional Order Sliding Mode Control With Reaching Law Approach, Mehmet Önder Efe
Turkish Journal of Electrical Engineering and Computer Sciences
Fractional order sliding mode control is studied in this paper. The control objectives are achieved by adopting the reaching law approach of sliding mode control. The main contribution of this work is to show that the philosophy of integer order sliding mode control is valid also for the systems represented by fractional order operators. A sufficient condition and its implications for stability are given. Matched and unmatched uncertainties are studied. The attractor nature of the switching manifold is analyzed together with a stable sliding subspace design condition. The claims are justified through a set of simulations and the results obtained …
Asynchronous Particle Swarm Optimization-Based Search With A Multi-Robot System: Simulation And Implementation On A Real Robotic System, Sali̇h Burak Akat, Veysel Gazi̇, Lino Marques
Asynchronous Particle Swarm Optimization-Based Search With A Multi-Robot System: Simulation And Implementation On A Real Robotic System, Sali̇h Burak Akat, Veysel Gazi̇, Lino Marques
Turkish Journal of Electrical Engineering and Computer Sciences
In this article we consider a version of the Particle Swarm Optimization (PSO) algorithm which is appropriate for search tasks of multi-agent systems consisting of small robots with limited sensing capability. The proposed method adopts asynchronous mechanism for information exchange and position (way point) updates of the agents. Moreover, at each (information exchange) step the agents communicate with only a possibly different subset of the other agents leading to a dynamic neighborhood topology. We implement the algorithm using the Player/Stage realistic robot simulator as well as on real KheperaIII robots using experimentally collected realistic data of ethanol gas concentration. Simulation …
A Model Based Nonlinear Adaptive Controller For The Passive Bilateral Telerobotic System, Ufuk Özbay, Erkan Zergeroğlu, İlyas Kandemi̇r
A Model Based Nonlinear Adaptive Controller For The Passive Bilateral Telerobotic System, Ufuk Özbay, Erkan Zergeroğlu, İlyas Kandemi̇r
Turkish Journal of Electrical Engineering and Computer Sciences
IIn this paper, we propose a new adaptive controller scheme for the bilateral telerobotic/teleoperation systems. The proposed controller achieves asymptotic tracking despite the parametric uncertainties associated with both master and slave robots while ensuring the passivity of the closed loop system. Extensive simulation studies are presented to illustrate the feasibility and efficiency of the proposed adaptive controller.
Modeling And Control Of Flow Problems By Adaptation-Based Linear Parameter Varying Models, Coşku Kasnakoğlu
Modeling And Control Of Flow Problems By Adaptation-Based Linear Parameter Varying Models, Coşku Kasnakoğlu
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper a systematic modeling and control approach for flow problems is considered. A nonlinear Galerkin model is obtained from the partial differential equations (PDEs) describing the flow; and a Linear Parameter Varying (LPV) model is constructed to approximate the Galerkin model, where the parameter variation of the LPV model is controller by an adaptation mechanism. The LPV model is then treated as a surrogate on which the control design is carried out, where the parameter variations provide a range of uncertainty in which the control design must perform satisfactorily. It is shown that if certain conditions are met, …
Simultaneous Rotor And Stator Resistance Estimation Of Squirrel Cage Induction Machine With A Single Extended Kalman Filter, Eşref Emre Özsoy, Meti̇n Gökaşan, Ovsanna Seta Estrada
Simultaneous Rotor And Stator Resistance Estimation Of Squirrel Cage Induction Machine With A Single Extended Kalman Filter, Eşref Emre Özsoy, Meti̇n Gökaşan, Ovsanna Seta Estrada
Turkish Journal of Electrical Engineering and Computer Sciences
Accurate knowledge of rotor and stator resistance variations in a squirrel-cage induction motor (SCIM) is crucial for the performance of sensorless control of SCIM over a wide range of speeds. This study seeks to address this issue with a single Extended Kalman Filter (EKF) based solution, which is also known to have accuracy limitations when a high number of parameters/states are estimated with a limited number of inputs. To this aim, different from the author's previous approach in operating several EKFs in an alternating manner (the so-called braided EKF), an 8^{th}-order EKF is implemented in this study to test its …
Analysis And Estimation Of Motion Transmission Errors Of A Timing Belt Drive, Ergi̇n Kiliç, Meli̇k Dölen, Ahmet Buğra Koku
Analysis And Estimation Of Motion Transmission Errors Of A Timing Belt Drive, Ergi̇n Kiliç, Meli̇k Dölen, Ahmet Buğra Koku
Turkish Journal of Electrical Engineering and Computer Sciences
This paper focuses on viable position estimation schemes for timing belt drives where the position of the carriage (load) is to be determined via reference models receiving input from a position sensor attached to the actuator of the timing belt. A detailed analysis of the transmission error sources is presented, and a number of relevant mathematical models are developed using a priori knowledge of the process. This paper demonstrates that such schemes are very effective when the drive system is not subjected to external loads and operating conditions do not change considerably i.e. ambient temperature, belt tension.
Precise Position Control Using Shape Memory Alloy Wires, Burcu Dönmez, Bülent Özkan, Fevzi̇ Suat Kadioğlu
Precise Position Control Using Shape Memory Alloy Wires, Burcu Dönmez, Bülent Özkan, Fevzi̇ Suat Kadioğlu
Turkish Journal of Electrical Engineering and Computer Sciences
Shape memory alloys (SMAs) are active metallic ``smart'' materials used as actuators and sensors in high technology smart systems [1]. The term shape memory refers to ability of certain materials to ``remember'' a shape, even after rather severe deformations: once deformed at low temperatures, these materials will stay deformed until heated, whereupon they will return to their original, pre-deformed ``learned'' shape [2]. This property can be used to generate motion and/or force in electromechanical devices and micro-machines. However, the accuracy of SMA actuators is severely limited by their highly nonlinear stimulus-response characteristics. In this work, modeling, simulation, and experimental efforts …
Design And Evaluation Of A Linear Switched Reluctance Actuator For Positioning Tasks, António Espírito Santo, Rosário Calado, Carlos Cabrita
Design And Evaluation Of A Linear Switched Reluctance Actuator For Positioning Tasks, António Espírito Santo, Rosário Calado, Carlos Cabrita
Turkish Journal of Electrical Engineering and Computer Sciences
This paper presents the development of a new linear switched reluctance actuator and confirms its applicability to perform positioning tasks. After the explanation of the actuator working principle and the presentation of its electromechanical topology, an analysis is accomplished using a finite elements tool. Based on the theoretical results, an experimental prototype that can develop 150 N was constructed. Its behaviour is observed under two different control methods implemented with microcontrollers. Initially, position is controlled applying a single pulse-driving scheme. Meanwhile, significant improvements are obtained with the introduction of a sliding-mode controller, allowing movements with 1 mm of resolution.