bluuebunny/crossref_metadata_2025_split huggingface dataset:
ROBUST EIGENVALUE ASSIGNMENT IN DESCRIPTOR SYSTEMS VIA OUTPUT FEEDBACK
Authors: Duan Guang‐Ren , Lamy James , Liu Guo‐Ping 
Published: September 2010

ABSTRACTBased on a recently proposed parametric approach for eigenstructure assignment in descriptor linear systems via output feedback, the robust eigenvalue assignment problem in descriptor linear systems via output feedback is solved. The problem aims to assign a set of finite closed‐loop eigenvalues which have minimum sensitivities with respect to perturbations in the closed‐loop coefficient matrices, while at the same time, guarantee the closed‐loop regularity. The approach optimizes the design parameters existing in the closed‐loop eigenvectors to achieve the minimum eigenvalue sensitivities, and use the extra degree of freedom existing in the solution of the gain matrix to further minimize the magnitude of the gain matrix and enhance the robustness of the closed‐loop regularity. The approach allows the finite closed‐loop eigenvalues to be optimized within desired regions, and is demonstrated to be simple and effective.
ACTIVE VIBRATION ISOLATION FOR A LONG RANGE SCANNING TUNNELING MICROSCOPE
Authors: Lan Kuo‐Jung , Yen Jia‐Yush , Kramar John A. 
Published: September 2010

ABSTRACTVibration isolation or control is critical for the optimum operation of the Molecular Measuring Machine (M3), a high‐resolution, length‐metrology instrument at the National Institute of Standards and Technology. This paper describes the extension of the M3 Mallock isolation suspension from passive to six degrees‐of‐freedom (DOF) active vibration isolation. System modeling is presented, and experimental system identification is carried out for the purpose of model verification. The paper then compares the vibration isolation performance achieved using a classical proportional‐integral‐derivative (PID) controller versus that achieved using a modified, model‐based, Linear‐Quadratic‐Gaussian (LQG) controller. Attenuation of 3 dB to 15 dB is achieved within the active vibration isolation control bandwidth, and images taken with the M3 scanning tunneling microscope (STM) probe show improved performance.
A PNEUMATIC POSITIONING DEVICE COUPLED WITH PIEZOELECTRIC SELF‐MOVING MECHANISM
Authors: Liu Yung‐Tien , Lee Chen‐Hao , Fung Rong‐Fong 
Published: September 2010

ABSTRACTThis paper reports a new pneumatic positioning device coupled with a piezoelectric self‐moving mechanism to overcome the main disadvantages of the inherent poor positioning accuracy obtained by traditional pneumatic cylinder. The new driving mechanism is to mount a piezoelectric Impact Drive Mechanism (IDM) to the controlled sliding table driven by the pneumatic cylinder. Based on the configuration, the first step of positioning process is to actuate the sliding table with rough position accuracy but with the benefits of high‐speed and large‐range due to the pneumatic cylinder. The second step is to drive the sliding table with high position accuracy by utilizing the impact force of IDM. The experimental results show that the controlled sliding table is successfully positioned in 0.236 s with rough accuracy of 10 μm and with the stroke of 100 mm by utilizing the pneumatic cylinder, and the final positioning accuracy of 10 nm with respect to the terminated position of the first‐stage control is obtained in 1.479 s due to the actuations of IDM. It is shown that the pneumatic positioning device coupled with IDM has attractive practical applications in the field of precision industry.
ULTRA‐FINE TRACKING CONTROL ON PIEZOELECTRIC ACTUATED MOTION STAGE USING PIEZOELECTRIC HYSTERETIC MODEL
Authors: Huang Yi‐Cheng , Lin De‐Yao 
Published: September 2010

ABSTRACTThe tracking control accuracy of the piezoelectric actuator (PEA) is limited due to its inherent hysteresis nonlinearity. A new piezoelectric‐actuator model is synthesized based on two first‐order transfer systems in parallel with two tuned parameters determined from one experiment. Two open‐loop tracking controllers are implemented with the proposed model to compensate the hysteresis of linear positioning. Numerical simulations and experimental tests on the tracking of sinusoidal and triangular waveforms with signal frequencies ranging from 1Hz to 30 Hz are revisited and compared with the conventional Bouc‐Wen and Duhem models. Experimental results reveal that the RMS tracking error can be reduced to less than 2% of the maximum traveling distance without any feedback sensor. When a piezoelectric actuated on a two Degree‐Of‐Freedom (DOF) monolithic motion stage was employed, the RMS tracking error was 50 nm within the measured sensor accuracy.
NECESSARY AND SUFFICIENT CONDITIONS FOR DEADLOCKS IN FLEXIBLE MANUFACTURING SYSTEMS BASED ON A DIGRAPH MODEL
Authors: Zhang Wenle , Judd Robert P. , Deering Paul 
Published: September 2010

ABSTRACTAs typical discrete event systems, flexible manufacturing systems have been extensively studied in such aspects as modeling, control and performance analysis. One important topic in the study of such systems is the deadlock detection, prevention and avoidance. In the past decade, two major modeling formalisms, i.e., Petri nets and digraphs, have been adopted for developing deadlock control policies for flexible manufacturing systems. In this paper, the concepts of slack, knot, order and effective free space of circuits in the digraph are established and used to concisely and precisely quantify the sufficient conditions for a system state to be live. Necessary conditions for this liveness is quantified for a special class of system states ‐ called evaluation states. The significance of the result is that the conditions are true for avoiding both primary deadlocks and impending deadlocks that are arbitrary steps away from a primary one, whereas only second level deadlocks have been studied in the literature. Examples are provided to illustrate the method.
DYNAMIC SCHEDULING FOR A SINGLE MACHINE SYSTEM UNDER DIFFERENT SETUP AND BUFFER CAPACITY SCENARIOS
Authors: Martinelli Francesco , Valigi Paolo 
Published: September 2010

ABSTRACTThe problem of dynamic scheduling for single machine manufacturing systems has been extensively studied in the past under different setup scenarios, mainly for systems with infinite buffer capacity. This paper addresses a general framework and investigates similarities and differences between policies optimal if setup times and costs are or are not negligible, if buffers have a finite or an infinite capacity. The cost function takes into account of backlog and surplus, but also includes a demand loss component if buffers have a finite capacity and a setup cost if not negligible. Both a steady state and a transient optimization problem are considered and already known results are compared and extended to complete the analysis.
MINIMAL VALID AUTOMATA OF SAMPLE SEQUENCES FOR DISCRETE EVENT SYSTEMS
Authors: Chung Sheng‐Luen , Li Chung‐Lun 
Published: September 2010

ABSTRACTMinimal valid automata (MVA) refer to valid automata models that fit a given input‐output sequence sample from a Mealy machine model. They are minimal in the sense that the number of states in these automata is minimal. Critical to system identification problems of discrete event systems, MVA can be considered as a special case of the minimization problem for incompletely specified sequential machine (ISSM). While the minimization of ISSM in general is an NP‐complete problem, various approaches have been proposed to alleviate computational requirement by taking special structural properties of the ISSM at hand. In essence, MVA is to find the minimal realization of an ISSM where each state only has one subsequent state transition defined. This paper presents an algorithm that divides the minimization process into two phases: first to give a reduced machine for the equivalent sequential machine, and then to minimize the reduced machine into minimal realization solutions. An example with comprehensive coverage on how the associated minimal valid automata are derived is also included.
A CLOSED‐LOOP SUBSPACE IDENTIFICATION METHOD FOR CONTINUOUS‐TIME SYSTEMS BASED ON δ‐OPERATOR MODEL
Authors: Huang Dongliang , Katayama Tohru 
Published: September 2010

ABSTRACTThis paper is concerned with a subspace identification of a continuous‐time plant operating in closed‐loop in the framework of the joint input‐output approach. The main procedure consists of two steps. Firstly, the dual‐Youla parametrization of the plant is used for obtaining an equivalent open‐loop problem to the original closed‐loop identification problem. Then, a δ‐operator based IV‐MOESP type subspace identification algorithm is developed to estimate the state space model for the joint input‐output process, whereby a higher‐order state space model of the plant is obtained by an algebraic operation. Subsequently, a model reduction procedure is employed to derive a lower‐order plant model removing irrelevant modes from the higher order model. Simulation results by using numerical and chemical plant models demonstrate the feasibility of the proposed method.
DYNAMIC POSITIONING CONTROL OF SHIPS VIA RELAY OBSERVER DESIGN
Authors: Moreno‐Valenzuela Javier , Acho‐Zuppa Leonardo 
Published: September 2010

ABSTRACTA dynamically positioned ship maintains its position (fixed location or predetermined track) exclusively by means of active thrusters. In this paper, a control scheme for dynamic positioning control of ships using a relay observer design is presented. Our analysis relies on nonsmooth strict Lyapunov functions to demonstrate global asymptotic stability of the closed‐loop system equilibrium. Using simulation results we illustrate the good performance of the proposed scheme under noisy ship position measurements.
NETWORK‐INDUCED DELAY‐DEPENDENT H∞ CONTROLLER DESIGN FOR A CLASS OF NETWORKED CONTROL SYSTEMS
Authors: Jiang Xiefu , Han Qing‐Long 
Published: September 2010

ABSTRACTThis paper is concerned with the problem of robust H∞ controller design for a class of uncertain networked control systems (NCSs). The network‐induced delay is of an interval‐like time‐varying type integer, which means that both lower and upper bounds for such a kind of delay are available. The parameter uncertainties are assumed to be normbounded and possibly time‐varying. Based on Lyapunov‐Krasovskii functional approach, a robust H∞ controller for uncertain NCSs is designed by using a sum inequality which is first introduced and plays an important role in deriving the controller. A delay‐dependent condition for the existence of a state feedback controller, which ensures internal asymptotic stability and a prescribed H∞ performance level of the closed‐loop system for all admissible uncertainties, is proposed in terms of a nonlinear matrix inequality which can be solved by a linearization algorithm, and no parameters need to be adjusted. A numerical example about a balancing problem of an inverted pendulum on a cart is given to show the effectiveness of the proposed design method.
H2‐OPTIMAL SAMPLED‐DATA CONTROL FOR PLANTS WITH MULTIPLE INPUT AND OUTPUT DELAYS
Authors: Polyakov Konstantin Yu. 
Published: September 2010

ABSTRACTThe sampled‐data H2‐optimization problem for plants with multiple input and output delays is considered. An equivalent discrete‐time system is constructed and numerical algorithm for computing matrices of its state‐space realization is presented. It is proved that stability of this system is equivalent to stability of original sampled‐data system. The proposed method can be applied to a wide class of digital control problems for continuous‐time plants with multiple input and output delays.
SCHEDULING AND CONTROL CO‐DESIGN FOR DELAY COMPENSATION IN THE NETWORKED CONTROL SYSTEM
Authors: Chen Liang , Zhang Jianming , Wang Shuqing 
Published: September 2010

ABSTRACTThe networked control system (NCS) is currently receiving increasing attention from researchers. Researches on this subject, however, have not considered the co‐design of network quality of service (QoS) and control quality of performance (QoP). This paper proposes a novel NCS design framework based on scheduling and control co‐design to compensate for random network‐induced delays. In the framework, a scheduling algorithm used to find the optimal sampling regions of control loops performs rough adjustment and guarantees the network QoS, while a novel adaptive fuzzy PID controller is designed to perform accurate adjustment to guarantee the control QoP. Practical application results obtained with a multi‐loop NCS show that the framework can ensure satisfactory performance due to its robustness against network uncertainty.
STATE‐SPACE DIGITAL PID CONTROLLER DESIGN FOR MULTIVARIABLE ANALOG SYSTEMS WITH MULTIPLE TIME DELAYS
Authors: Madsen Jennifer M. , Shieh Leang‐San , Guo Shu‐Mei 
Published: September 2010

ABSTRACTThis paper presents a discrete‐time state‐space methodology for optimal design of digital PID controllers for multivariable analog systems with multiple time delays. The multiple time‐delayed multivariable analog systems are formulated in a state‐space generic form so that the exact discrete‐time state‐space model can be constructed. Then, the optimal digital PID controller is designed via a state‐feedback and state‐feedforward LQR approach. The developed PID controller can be applied to a general time‐delayed multivariable analog system represented by a semi‐proper or strictly proper transfer function matrix. Illustrative examples are given to compare the performance of the proposed approach with alternative techniques.
DELAY‐DEPENDENT ROBUST CONTROL FOR UNCERTAIN SINGULAR TIME‐DELAY SYSTEMS
Authors: Su Hongye , Ji Xiaofu , Chu Jian 
Published: September 2010

ABSTRACTThe problem of delay‐dependent robust stabilization for uncertain singular time‐delay systems is investigated in this paper. The parameter uncertainty is assumed to be norm‐bounded and possibly time‐varying, while the time delay considered here is assumed to be constant but unknown. A delay‐dependent condition is presented for a singular time‐delay system to be regular, impulse free, and stable, based on which robust stability analysis and the robust stabilization problem are studied. An explicit expression for the desired state‐feedback control law is also given. The obtained results are formulated in terms of linear matrix inequalities (LMIs), which involve no decomposition of the system matrices. Some numerical examples are given to show the efficiency of the theoretical conditions.
LMI OPTIMIZATION APPROACH FOR DELAY‐DEPENDENT H∞ CONTROL OF TIME‐VARYING DELAY SYSTEMS
Authors: Lien Chang‐Hua , Yu Ker‐Wei 
Published: September 2010

ABSTRACTIn this paper, the robust delay‐dependent H∞ control for a class of uncertain systems with time‐varying delay is considered. An improved state feedback H∞ control is proposed to minimize the H∞‐norm bound via the LMI optimization approach. Based on the proposed result, delay‐dependent criteria are obtained without using the model transformation technique or bounded inequalities on cross product terms. The linear matrix inequality (LMI) optimization approach is used to design the robust H∞ state feedback control. Some numerical examples are given to illustrate the effectiveness of the approach.
ADAPTIVE COORDINATED DECENTRALIZED CONTROL OF STATE DELAYED SYSTEMS WITH ACTUATOR FAILURES
Authors: Mirkin Boris M. , Gutman Per‐Olof 
Published: September 2010

ABSTRACTThis paper develops an adaptive state feedback coordinated decentralized control scheme for a class of dynamic systems with state delay in subsystems and in the interconnections and in the presence of unknown actuator failures in each subsystem. The main contributions of this paper are the development of a new controller parametrization which attempt to anticipate the future states and failures, the introduction of an appropriate Lyapunov‐Krasovskii type functional to design the adaptation algorithms, and a stability proof.
FLEXIBLE SPACECRAFT VIBRATION SUPPRESSION USING PWPF MODULATED INPUT COMPONENT COMMAND AND SLIDING MODE CONTROL
Authors: Hu Qing‐lei , Ma Guang‐fu 
Published: September 2010

ABSTRACTThis paper presents a dual‐stage control system design method for the rotational maneuver and vibration stabilization of a spacecraft with flexible appendages. In this design approach, attitude control system and vibration suppression were designed separately using lower order model. The design of attitude controller was based on sliding mode control (SMC) theory leading to a discontinuous control law. This controller accomplishes asymptotic attitude maneuvering in the closed‐loop system and is insensitive to the interaction of elastic modes and uncertainty in the system. The shaped command input controller based on component synthesis vibration suppression (CSVS) method is designed for reduction of flexible mode vibration, which only requires information about natural frequency and damping of the closed system. Additionally, to extend the CSVS method to the system with on‐off actuators, pulse‐width pulse‐frequency (PWPF) modulation is employed to control the thruster firing and integrated with the CSVS method. Simulation results have been proven the potential of this technique to control flexible spacecraft.
INTERNET‐BASED REAL‐TIME CONTROL ARCHITECTURES WITH TIME‐DELAY/PACKET‐LOSS COMPENSATION
Authors: Ji Kun , Kim Won‐jong , Srivastava Abhinav 
Published: September 2010

ABSTRACTThe main objective of this paper is to demonstrate the feasibility of Internet‐based real‐time control. A novel client/server‐based architecture for Internet‐based supervisory control with a Common Gateway Interface/Hyper Text Markup Language (CGI/HTML) interface is presented. A real‐time operating environment was established for closed‐loop control over Ethernet. We conceived of an autoregressive (AR) prediction scheme and a novel compensation algorithm to compensate for network‐induced time delays and data‐packet losses simultaneously. We constructed an open‐loop unstable ball magnetic‐levitation (maglev) setup as a test bed to validate the two proposed control architectures. Experimental results proved the feasibility of Internet‐based real‐time control and verified the effectiveness of the proposed time‐delay/packet‐loss compensation algorithm in networked feedback control systems.
ROBUST FAULT‐TOLERANT CONTROL FOR A CLASS OF SWITCHED NONLINEAR SYSTEMS IN LOWER TRIANGULAR FORM
Authors: Wang Rui , Jin Gang , Zhao Jun 
Published: September 2010

ABSTRACTThis paper investigates the problem of robust fault‐tolerant control for a class of uncertain switched nonlinear systems in lower triangular form. A system of this class involves parameter uncertainties and unknown nonlinear disturbances. A sufficient condition for the problem to be solvable under arbitrary switching is given in terms of linear matrix inequalities (LMIs). State feedback controllers of subsystems are designed by using the solutions to the matrix inequalities to guarantee global asymptotic stability of the closed‐loop systems in presence of actuator failures and under arbitrary switching. A practical system of hybrid haptic display is analyzed to demonstrate the proposed design method.
Robust Tracking Control For A Wheeled Mobile Manipulator With Dual Arms Using Hybrid Sliding‐Mode Neural Network
Authors: Tsai Ching‐Chih , Cheng Meng‐Bi , Lin Shui‐Chun 
Published: September 2010

ABSTRACTIn this paper, a robust tracking controller is proposed for the trajectory tracking problem of a dual‐arm wheeled mobile manipulator subject to some modeling uncertainties and external disturbances. Based on backstepping techniques, the design procedure is divided into two levels. In the kinematic level, the auxiliary velocity commands for each subsystem are first presented. A sliding‐mode equivalent controller, composed of neural network control, robust scheme and proportional control, is constructed in the dynamic level to deal with the dynamic effect. To deal with inadequate modeling and parameter uncertainties, the neural network controller is used to mimic the sliding‐mode equivalent control law; the robust controller is designed to compensate for the approximation error and to incorporate the system dynamics into the sliding manifold. The proportional controller is added to improve the system's transient performance, which may be degraded by the neural network's random initialization. All the parameter adjustment rules for the proposed controller are derived from the Lyapunov stability theory and e‐modification such that uniform ultimate boundedness (UUB) can be assured. A comparative simulation study with different controllers is included to illustrate the effectiveness of the proposed method.
ON QUALITATIVE BEHAVIOR OF A CLOSED‐LOOP QUANTIZED SYSTEM
Authors: Askari J. , Lunze J. , Jabedar‐Maralani P. 
Published: September 2010

ABSTRACTThis paper concerns the characterization of qualitative behavior of a closed‐loop quantized system. A quantized system is a dynamical system, which instead of knowing its state x(t) and its input u(t) precisely, their qualitative values [x(t)] and [u(t)] at a discrete time set T = {t0, t1, …, tk, …} are known. The qualitative state [x(t)] and the qualitative input [u(t)] are qualitative assessments of their precise values x(t) and u(t) respectively, and they can be related to each other via a non‐deterministic automaton description. The aim is to characterize the state behavior of a quantized system whenever its nondeterministic automaton description is given. The first result of the paper is derivation of a representation W(k + 1) = AW(k) for a nondeterministic closed‐loop automaton. The second result of the paper shows that the state‐behavior of a closed‐loop quantized system can be characterized according to the eigenvalues of matrix A in a similar manner with usual linear discrete‐time systems.
GLOBAL ROBUST SERVOMECHANISM OF A CLASS OF NONLINEAR SYSTEMS USING OUTPUT FEEDBACK
Authors: Chen Zhiyong , Huang Jie 
Published: September 2010

ABSTRACTThe robust servomechanism problem (alternatively, output regulation problem) of the class of nonlinear systems in lower triangular form has been extensively studied in recent years. The semi‐global solution was first given by either state feedback or output feedback. The global solution by state feedback was given very recently. However, the global solution by output feedback has long been an open problem. In this paper, we present a set of solvability conditions of the global robust servomechanism problem for this class of nonlinear systems by output feedback.
GENERATION OF EXACT QFT BOUNDS FOR PLANTS WITH AFFINELY DEPENDENT UNCERTAINTIES
Authors: Yang Shih‐Feng 
Published: September 2010

ABSTRACTThis paper presents an efficient method for the generation of exact QFT bounds for robust sensitivity reduction and gain‐phase margin specifications for plants with affinely dependent uncertainties. It is shown that, for a plant withmaffinely dependent uncertainties, the exact QFT bounds for robust sensitivity reduction and gain‐phase margin specifications at a given frequency and controller phase can be computed by solvingm2m‐1bivariate polynomial inequalities corresponding to the edges of the parameter domain box. Moreover, the solution set for each bivariate polynomial inequality can be computed by solving for the real roots of one fourth‐order and six second‐order polynomials. This avoids the unfavorable trade‐off between the computational burden and the accuracy of QFT bounds that has arisen in the application of many existing QFT bound generation algorithms. Numerical examples are given to illustrate the proposed method and its computational superiority.