bluuebunny/crossref_metadata_2025_split huggingface dataset:
ADAPTIVE VARIABLE STRUCTURE CONTROL OF UNCERTAIN SYSTEMS CONTAINING UNKNOWN GAIN REDUCTION TOLERANCE
Authors: Yan Jun‐Juh , Lin Jui‐Sheng , Shyu Kuo‐Kai 
Published: September 2010

ABSTRACTIn this paper, an adaptive variable structure controller (AVSC) is presented for a class of uncertain systems subjected to input nonlinearities. Using an adaptive technique, an AVSC is then proposed to ensure the asymptotical convergence of the switching quantity even without involving the bound of the gain reduction tolerance. On the switching surface, the investigated uncertain system still bears the insensitivity to the uncertainties and disturbances as the systems with linear input. An illustrative example is given to demonstrate the effectiveness of the proposed AVSC design method.
ADAPTIVE CONTROL DESIGN FOR NONLINEARLY PARAMETERIZED SYSTEMS WITH A TRIANGULAR STRUCTURE
Authors: Yokoi Kiyoshi , Hung N.V.Q. , Tuan H.D. , Hosoe Shigeyuki 
Published: September 2010

ABSTRACTA novel adaptive backstepping design for a class of nonlinearly parameterized systems with a triangular structure is proposed. Under the Lipschitz condition with respect to unknown parameters of the system, an effective adaptive controller is designed without the requirement on the compactness of the unknown parametric set. Especially, the proposed adaptive control enables the advantage of “tuning function concept”, which results in only one estimation law for the unknown parameters. Our simulation with induction motor model particularly shows the viability of the obtained results.
A STATE‐SPACE APPROACH TO QUANTIZATION COARSENESS FOR QUADRATIC STABILIZATION OF SINGLE‐INPUT SYSTEMS
Authors: Haimovich Hernan , Serony María M. 
Published: September 2010

ABSTRACTThe input‐space‐based concept of quantization density recently introduced in the literature for single‐input systems can be regarded as a measure of the amount of information that a static feedback law employs. Here, we introduce a concept of quantizer coarseness for static quantizers from a purely state‐space standpoint, by means of explicit geometric considerations. We then analyze the links between this concept and the input‐space‐based quantization density. We thus provide an alternative state‐space‐based interpretation of coarse quantizers. We show how to directly apply the state‐space‐based concept of quantizer coarseness to design static output feedback strategies that employ quantizers of infimum density and to recover a well‐known result when a specific type of state quantizers is considered.
DISCRETIZATION OF COCURRENT REACTION‐ADVECTION PROCESSES PRESERVING THE FIR PROPERTY
Authors: Choi Jinhoon 
Published: September 2010

ABSTRACTA cocurrent reaction‐advection process represented by a system of first order hyperbolic partial differential equations (PDE's) has a desirable feature of finite impulse response (FIR) that allows easy identification and control. However, this desirable characteristic hasn't been exploited since all of the known finite difference discretization schemes do not preserve this desirable characteristic. In this note, we propose a finite difference discretization scheme that preserves the FIR property.
A STABLE ON‐LINE SELF‐TUNING OPTIMAL PID CONTROLLER FOR A CLASS OF UNKNOWN SYSTEMS
Authors: Huang Han‐Pang , Lin Ching‐Hung 
Published: September 2010

ABSTRACTIn this paper, a novel self‐tuning method of optimal PID control laws is proposed for both continuous‐time systems and discrete‐time systems. The controlled plant is assumed to be unknown except the system order (or system delay) and the direction of transmitting control input. Through the minimization of PID gains subject to the Lyapunov stability based reaching condition, the tuning of the three PID control gains is transformed to solve the inequality constraint optimization problem. An unknown SISO nonlinear system subject to a unit step input, and the tracking control problem of the piezoelectric actuator (PZA) with unknown dynamics are simulated. The simulation results show that the excellent tracking performance can be achieved.
REAL‐TIME IMPLEMENTATION OF A DECENTRALIZED CONTROL FOR AN OPEN IRRIGATION CANAL PROTOTYPE
Authors: Begovich Ofelia , Felipe Juan C. , Ruiz Victor M. 
Published: September 2010

ABSTRACTThis paper presents a real‐time implementation of a decentralized LQG controller to regulate the downstream levels at the end of the pools in a four‐pool open irrigation canal prototype with an upstream control concept. The objective of the controller is to keep the downstream level at a constant target value in despite of flow disturbances. Controller synthesis uses a “black box” input‐output identified linear model. A previous interaction analysis, via Relative Gain Array “RGA”, carried on the process model was made to verify the feasibility to design a decentralized control. The real‐time close‐loop results show satisfactory performance and they are compared with those obtained with a centralized LQG controller.
ROBUST POLE ASSIGNMENT VIA OUTPUT FEEDBACK IN DESCRIPTOR LINEAR SYSTEMS WITH STRUCTURAL PARAMETER PERTURBATIONS
Authors: Duan Guang‐Ren , Zhang Biao 
Published: September 2010

ABSTRACTThe problem of eigenvalue assignment via output feedback with minimum sensitivity in multivariable descriptor linear systems with structural parameter perturbations is considered. Based on an eigenstructure assignment result for descriptor linear systems via output feedback and a result for generalized eigenvalue sensitivity problem of matrix pairs, parametric representations of the closed‐loop eigenvalue sensitivities to the perturbed elements in the open‐loop system matrices are obtained. An effective algorithm for eigenvalue assignment with minimum sensitivity in descriptor linear systems via output feedback is then proposed. The algorithm does not contain ‘going back’ procedures, and allows the closed‐loop eigenvalues to be conveniently optimized within desired regions. Computational results show its effect and simplicity.
USING LEAST SQUARE SVM FOR NONLINEAR SYSTEMS MODELING AND CONTROL
Authors: Zhang Haoran , Wang Xiaodong , Zhang Changjiang , Xu Xiuling 
Published: September 2010

ABSTRACTSupport vector machine is a learning technique based on the structural risk minimization principle, and it is also a class of regression method with good generalization ability. The paper firstly introduces the mathematical model of regression least squares support vector machine (LSSVM), and designs incremental learning algorithms by the calculation formula of block matrix, then uses LSSVM to model nonlinear system, based on which to control nonlinear systems by model predictive method. Simulation experiments indicate that the proposed method provides satisfactory performance, and it achieves superior modeling performance to the conventional method based on neural networks, moreover it achieves well control performance.
Robust Neural Network Controller Design For A Biaxial Servo System
Authors: Yu Chih‐Hsien , Chen Tien‐Chi 
Published: September 2010

ABSTRACTA robust control method for synchronizing a biaxial servo system motion is proposed in this paper. A new neural network based cross‐coupled control and neural network techniques are used together to cancel out the skew error. In the proposed control scheme, the conventional fixed gain PID cross‐coupled controller (PIDCCC) is replaced with the neural network cross‐coupled controller (NNCCC) to maintain biaxial servo system synchronization motion. In addition, neural network PID position velocity and velocity controllers provide the necessary control actions to maintain synchronization while following a variable command trajectory. This scheme provides strong robustness with respect to uncertain dynamics and nonlinearities. The simulation results reveal that the proposed control structure adapts to a wide range of operating conditions and provides promising results under parameter variations and load changes.
A Novel Method Of Controller Design For Simultaneous Stabilization And Performance Improvement Of An Electromagnetic Levitation System
Authors: Banerjee Subrata , Kumar T. K. Sunil , Pal Jayanta , Prasad Dinkar 
Published: September 2010

ABSTRACTThis paper describes design and implementation of a control philosophy for simultaneous stabilization and performance improvement of an electromagnetic levitation system. An electromagnetic levitation system is an inherently unstable and strongly nonlinear system. To determine the overall closed loop stability for such a system, cascade lead‐lag compensation has mostly been reported [1,2]. However, a single lead controller can not satisfy both stability and performance for such unstable systems [3]. Performance enhancement to satisfy the conflicting requirements of fast response with almost zero overshoot and zero steady state error has been successfully achieved by using a two loop controller configuration. The lead controller in the inner loop is designed to ensure stability while the outer loop PI controller is designed for performance enhancement. This approach decouples the twin requirements of stabilization (by the inner loop) and performance achievement (by the outer PI loop). The outermost PI controller has been designed using the ‘Approximate Model Matching’ technique [4]. The proposed control strategy has been implemented and the experimentation has been demonstrated successfully. Different experimental results have been included for verification.
Delay‐Dependent Robust Stability Criteria For Uncertain Neutral Systems With Mixed Time‐Varying Discrete And Neutral Delays
Authors: Parlakçi M. N. Alpaslan 
Published: September 2010

ABSTRACTIn this paper, a new class of augmented quasi full size Lypunov‐Krasovskii functional is introduced for the robust stability of uncertain neutral systems with mixed time‐varying discrete and neutral delays. The nonlinear parameter perturbations and norm‐bounded uncertainties are taken into consideration separately. Delay‐dependent robust stability criteria are derived in the form of linear matrix inequalities. Numerical examples are presented to illustrate the significant improvement on the conservativeness of the delay bound over some reported results in the literature.
Adaptive Friction Compensation For Tracking Control Of Mechanisms
Authors: Guerra R. , Acho L. 
Published: September 2010

ABSTRACTBecause friction is a phenomenon that is present in the vast majority of mechanical systems producing some unwanted effects such as tracking errors, limit cycles, and stick‐slip motion, friction model based compensation has been previously proposed. We present a simple adaptive friction compensator, developed from a simple friction model, that achieves the control objective (friction compensation). This simple model was effectively used to obtain a friction compensator with smooth terms avoiding the use of signum and absolute functions presented in previously reported works on friction compensation. Considering that the velocity is bound away from zero and using Lyapunov stability analysis, exponential stability of the closed loop system is shown; i.e., the tracking errors and the parameter estimation error converge exponentially to zero. Because our friction compensator is based on a simple friction model, numerical experiments using a more representative friction model are given to support our theoretical findings.
DSP‐BASED CONTROLLER DESIGN OF AN XY‐TABLE AND ITS APPLICATION TO VIRTUAL FISHING SYSTEM
Authors: Wang Ming‐Shyan , Lee Jing , Huang Chih‐Kai 
Published: September 2010

ABSTRACTThe paper is focused on controller design of a hybrid XY‐table equipped with both a PMSM and a PMLSM and application of the XY‐table system to a virtual fishing system (VFS), which incorporates a boat simulator, an interactive fishing rod system, virtual reality fishing scenes, and a player in the loop. The fishing rod system consists of the XY‐table system acting as interactive force feedback hardware. Adaptive fuzzy control is adopted in the controller to track the command trajectory. The fishing boat is simulated by a three‐axis manipulator, which is composed of three pneumatic cylinders serving as extensive linkages. Through the shunt combination of the cylinders, the movement of the fishing boat can be arbitrarily adjusted. Summarily, VFS creates a spontaneous and interactive environment and offers the experience of fishing in a remote location on the sea at home or at the amusement park.
FAULT TOLERANT CONTROL OF FLEXIBLE SMART STRUCTURES USING ROBUST DECENTRALIZED FAST OUTPUT SAMPLING FEEDBACK TECHNIQUE
Authors: Bandyopadhyay B. , Manjunath T.C. 
Published: September 2010

ABSTRACTThis paper presents the modeling, design and simulation of a Robust Decentralized Fast Output Sampling (RDFOS) feedback controller for the vibration control of a smart structure (flexible cantilever beam) when there is actuator failure. The beam is divided into 8 finite elements and the sensors / actuators are placed at finite element positions 2, 4, 6, and 8 as collocated pairs. The smart structure is modeled using the concepts of piezoelectric theory, Euler‐Bernoulli beam theory, Finite Element Method (FEM) techniques and the state space techniques. Four multi‐variable state‐space models of the smart structure plant are obtained when there is a failure of one of the four actuators to function. The effect of failure of one of the piezo actuators to function during the vibration of the beam is observed. The tip displacements, open and closed loop responses with and without the controller are observed. For all of these models, a common stabilizing state feedback gain F is obtained. A robust decentralized fast output sampling feedback gain L which realizes this state feedback gain is obtained using the LMI approach. In this designed control law, the control inputs to each actuator of the multi‐model representation of the smart structure is a function of the output of that corresponding sensor only and the gain matrix has got all off‐diagonal terms zero and this makes the control design a robust decentralized one. Then, the performance of the designed smart system is evaluated for Active Vibration Control (AVC). The robust decentralized FOS controller obtained by the designed method requires only constant gains and hence may be easier to implement in real time.
OPTIMIZATION OF DECENTRALIZED PI/PID CONTROLLERS BASED ON GENETIC ALGORITHM
Authors: Li Donghai , Gao Furong , Xue Yali , Lu Chongde 
Published: September 2010

ABSTRACTIn this paper, an optimization method of tuning decentralized PI/PID controllers based on genetic algorithms is presented. First, the existence of decentralized PI controllers with integrity is examined. Then, stable regions of each PI/PID controller parameters are calculated as the feasible area to be exploited, and the optimal PI/PID controllers are obtained by using a real‐coded genetic algorithm with elitist strategy, to meet the design specifications for the whole control system. The proposed method is applied to six examples from literature. Simulation results demonstrate that the proposed decentralized PI control is compatible to the referenced method while the decentralized PID control is better than the referenced method, and the proposed method is feasible for more complicated control systems optimizations.
SLIDING MODE PREDICTION TRACKING CONTROL DESIGN FOR UNCERTAIN SYSTEMS
Authors: Xiao Lingfei , Su Hongye , Chu Jian 
Published: September 2010

ABSTRACTIn this paper, a tracking control algorithm based on sliding mode prediction for a class of discrete‐time uncertain systems is presented. By creating a special model to predict the future sliding mode function value and by combining feedback correction and receding horizon optimization approaches, which are extensively applied in predictive control strategy, a discrete‐time sliding mode control law for tracking problem is constructed. With the designed control law, closed‐loop systems have strong robustness to matched or unmatched uncertainties as they eliminate chattering. Besides, in the robustness analysis, the boundary condition for uncertainties, which is a universal presupposition in sliding mode control method, is not required. Numerical simulation and cart‐pendulum experiment results illustrate the validity of the proposed algorithm.
ROBUST OBSERVER DESIGN FOR THERMOACOUSTIC DYNAMICS WITH DISTRIBUTED‐DELAY HEAT INPUT
Authors: Hong Boe‐Shong , Lin Tsu‐Yu 
Published: September 2010

ABSTRACTThis paper develops a strategy for the design of robust observers upon thermoacoustic dynamics with both spatial and temporal dimension‐infiniteness, model‐truncation error and exogenous disturbance. It helps the identification of their assumed flame dynamics that is feedback‐interconnected with the thermoacoustic dynamics in a combustion chamber and is usually to‐be‐identified. This paper formulates the proceedings to the proposed strategy and performs numerical tests for such a strategy.
SLIDING SURFACE MATCHED CONDITION IN SLIDING MODE CONTROL
Authors: Xiang Ji , Su Hongye , Chu Jian , Wei Wei 
Published: September 2010

ABSTRACTIn this paper, the recently developed sliding surface matching condition (SSMC) is viewed from a new point that the mismatched uncertain term should satisfy the minimum‐phase condition for the nominal system. With this new viewpoint, SSMC is extended to a more general class of system with nonlinear uncertainties. Finally, a numerical example demonstrates the developed results.
ROBUST H∞ CONTROL AND QUADRATIC STABILIZATION OF DISCRETE‐TIME SWITCHED SYSTEMS WITH NORM‐BOUNDED TIME‐VARYING UNCERTAINTIES
Authors: Ji Zhijian , Guo Xiaoxia , Wang Long , Xie Guangming 
Published: September 2010

ABSTRACTWe focus on robust H∞ control analysis and synthesis for discretetime switched systems with norm‐bounded time‐varying uncertainties. Sufficient conditions are derived to guarantee quadratic stability along with a prescribed H∞‐norm bound. Each of them can be dealt with as a linear matrix inequality (LMI) which can be tested with efficient algorithms. All the switching rules are constructively designed, and do not rely on any uncertainties.
ABSOLUTE STABILITY AND APPLICATION TO DESIGN OF OBSERVER‐BASED CONTROLLER FOR NONLINEAR TIME‐DELAY SYSTEMS
Authors: Hamed Bassem Ben , Abdallah Abdallah Ben , Chaabane Mohamed 
Published: September 2010

ABSTRACTIn this paper we present a new sufficient condition for absolute stability of delay Lure system. This condition improves the one given in [1]. We use this new criterion to construct an observer‐based control for a class of nonlinear time‐delay systems. Some examples are given to illustrate the results of this paper.
STRONG STABILIZATION OF MIMO SYSTEMS: A PROJECTION APPROACH
Authors: Saif Abdul‐Wahid A. 
Published: September 2010

ABSTRACTIn this paper, the strong stabilization problem of multivariable linear time‐invariant systems is considered. The approach is based on state‐space stable projection. The formulation is reduced to find a full rank constant output feedback. The computations involved are simpler than other methods.
UNKNOWN INPUTS OBSERVERS DESIGN FOR DELAY SYSTEMS
Authors: Darouach M. 
Published: September 2010

ABSTRACTThis paper concerns the design of functional, reduced and full order observers for linear time delay systems with unknown inputs. A new method generalizing those existing in the literature is presented for systems with unknown inputs, these unknown inputs are present in both the state and the measurement equations. Conditions for the existence of these observers are given and sufficient conditions for the stability independent of delays are derived using linear matrix‐inequality (LMI) formulation. The independent of internal delay and independent of delay cases are also presented. A numerical example is presented to illustrate our approach.
MULTI‐HOPPING INDUCED GAIN SCHEDULING FOR WIRELESS NETWORKED CONTROLLED SYSTEMS
Authors: Nikolakopoulos George , Panousopoulou Athanasia , Tzes Anthony , Lygeros John 
Published: September 2010

ABSTRACTA multi‐hopping induced gain scheduler for Wireless Networked Controlled Systems (WiNCS) is proposed. The control scheme is based on a client‐server architecture. The data packets are assumed to be carried over a network composed of wireless sensor nodes running the 802.11b protocol. The number of hops necessary for packets to reach their destinations is variable and depends on current traffic conditions. Changes in the number of hops induces changes in the latency times introduced by the communication network in the feedback loop. To deal with these changes an LQR‐output feedback scheme is introduced, whose parameters are adjusted according to the number of the hops. The weights of the LQR controllers are subsequently tuned using LMIs to ensure a prescribed stability margin despite the variable latency times. The overall scheme resembles a gain scheduled controller with the number of hops playing the role of the scheduling parameter. Simulation results on the NS‐2 simulator are provided to highlight the efficacy of the proposed scheme.
DESIGN OF REDUCED‐ORDER STATE/UNKNOWN INPUT OBSERVERS BASED ON A DESCRIPTOR SYSTEM APPROACH
Authors: Fernando T. , Trinh H. 
Published: September 2010

ABSTRACTThis paper solves the problem of estimating simultaneously a linear function of the state and unknown input of linear systems with unknown inputs. Here, the problem is conveniently solved by using the descriptor system approach. The observers proposed in this paper are of low‐order and do not include derivatives of the outputs. Conditions for the existence of reduced‐order observers are derived. Based on the newly derived existence conditions, a step‐by‐step design procedure is given. A numerical example is given to illustrate the attractiveness and simplicity of the design procedure.
PID TUNING FOR DOMINANT POLES AND PHASE MARGIN
Authors: Tang Wei , Wang Qing‐Guo , Ye Zhen , Zhang Zhiping 
Published: September 2010

ABSTRACTA simple PID tuning method for dominant pole placement and phase margin specification is proposed in this paper. Time domain specifications as settling time and percentage overshoot are represented by a pair of dominant poles, which is combined with phase margin specification to achieve closed‐loop stability and robustness. A graphical method is developed to determine PID settings to meet these specifications simultaneously. An example is given for illustration.
ROBUST OUTPUT FEEDBACK GUARANTEED COST CONTROL FOR 2‐D UNCERTAIN STATE‐DELAYED SYSTEMS
Authors: Peng Dan , Guan Xinping , Long Chengnian 
Published: September 2010

ABSTRACTThis paper considers the robust guaranteed cost control problem of two‐dimensional (2‐D) state‐delayed systems. First, the definition of guaranteed cost matrix is proposed and an upper bound of the cost function is given. Then, the guaranteed cost control problem is resolved. Furthermore, the minimum upper bound of the closed‐loop cost function is obtained by solving an optimization problem with LMIs' constraints. A numerical example demonstrates the effectiveness of our results.
VOLTAGE REGULATION OF A BUCK BOOST CONVERTER—A HYBRID CONTROL APPROACH
Authors: Sreekumar C. , Agarwal Vivek 
Published: September 2010

ABSTRACTIn this paper, the output voltage regulation problem in a buck boost converter is defined as a hybrid control problem. For control design, the mutually interacting continuous and discrete dynamics are modeled as a hybrid automaton. Thus, the control problem is defined as a guard selection problem of the hybrid automaton. The system trajectory is switched between different modes based on the guards to achieve the required voltage regulation. The guards defined are fixed surfaces represented in terms of the state variables for a given operating condition. The logic‐based switching in the state plane is stable in terms of the chaotic and bifurcation behavior. The effectiveness of the control scheme for buck and boost operation under line and load disturbances is demonstrated by simulation in the MATLAB‐SIMULINK environment and the results are presented.