bluuebunny/crossref_metadata_2025_split huggingface dataset:
PID‐Augmented Adaptive Control of a Gyro Mirror Los System
Authors: Tan K.K. , Lee T.H. , Khoh C.J. 
Published: September 2010

ABSTRACTIn this paper, a composite control scheme using a synergy of PID and adaptive control is proposed. The adaptive control component provides an adaptive feedforward control signal, while the PID component provides feedback control for robustness against modeling errors in the feedforward control design. The PID control can be automatically tuned using a relay. The control scheme developed is relevant to a large class of nonlinear servo‐mechanical systems, although in this paper, it is specifically implemented and demonstrated on a gyro mirror line‐of‐sight (LOS) system.
Tracking Control of Multiple Mobile Robots: A Case Study of Inter‐Robot Collision‐Free Problem
Authors: Jongusuk Jurachart , Mita Tsutomu 
Published: September 2010

ABSTRACTTracking control problem of multiple mobile robots is considered. Our system is composed of a reference and two follower robots of unicycle type, which have their own priority numbers. The purpose is to control the two followers so that the reference is tracked with arbitrary desired clearance and also to avoid an inter‐robot collision, which can occur randomly during the control process subjected to communication range limitation. We introduce two switching controllers and appropriately using their convergence properties leading to the collision‐free movement. Simulation results prove efficiency of our control techniques.
A State‐Space Based New Approach To The Directional Interpolation Problem
Authors: Horiguchi Kazumi 
Published: September 2010

ABSTRACTDirectional interpolation plays an important role in robust control, system realization and model reduction. Several solutions to various directional interpolation problems have been proposed. In this paper, we consider the directional interpolation problem in a general setting and present a statespace based new approach to solving the problem. The solution is simple, and its exposition is as self‐contained as possible. We describe all the (strictly) bounded real rational matrix functions that satisfy the directional interpolation requirements by means of linear fractional transformation. Moreover, we give a necessary and sufficient condition for the interpolating function to be unique and show that the unique interpolating function is an inner (a co‐inner). The main procedures used to generate the interpolating function consist of standard matrix operations consisting of easy numerical computations, so the present solution is significant from the numerical viewpoint as well as the analytical viewpoint.
Synthesis Of μ Controllers Using Statistical Iterations
Authors: Yang Ciann‐Dong , Tai Hung‐Chung 
Published: September 2010

ABSTRACTThis paper introduces the integration of robust control and quality control, based on which a statistical iteration scheme of μ synthesis is proposed. In this statistical solution, μ controller structures are fully flexible, and controller orders do not increase during iterations. In addition, it can reveal the directions of parameter changes, which may lead to improvements in the performance of the resulting controllers. Statistical interpretations and systematical procedures for this quality‐oriented control design are also addressed.
Two‐Stage Tracking Control Via Output Feedback
Authors: Wu Shang‐Teh 
Published: September 2010

ABSTRACTAn algorithm is proposed combining a high‐gain control and an internal‐model control for asymptotic output tracking in the presence of non‐decaying external disturbances. The plant output is the only signal used in the feedback loops. The algorithm is divided into two stages: high‐gain control is activated in the transient phase, forcing the output to quickly approach the reference trajectory, and is then taken over by an internal‐model controller in the steady phase so that perfect output tracking can be achieved with moderate gains and smooth control efforts. Smooth transition between the two control laws is ensured through an internal‐model observer, which serves as a relaying mechanism between the high‐gain control and the internal‐model control.
Exponential Stabilization of Bilinear Systems With Open‐Loop Unstable Dynamics
Authors: Hwang Yean‐Ren 
Published: September 2010

ABSTRACTThe quadratic control (or its modification) can stabilize a homogeneous bilinear system asymptotically (or exponentially) if its open‐loop dynamics are neutrally stable. When the open‐loop dynamics are unstable, the quadratic control can only bring the system state to a bounded region around the origin. In this paper, we propose a new nonlinear control which can drive the state of an open‐loop unstable system to the origin exponentially. This control algorithm can be easily extended to time varying systems with slight modification.
Stability Analysis of Linear Shift‐Invariant Dynamics in Honeycomb Structure
Authors: Ooba Tatsushi , Funahashi Yasuyuki 
Published: September 2010

ABSTRACTThis paper deals with the stability of linear shift‐invariant multidimensional dynamical systems defined on honeycomb structure. Two different honeycomb structures are discussed. The local dynamical states are assumed to be distributed to honeycomb cells in the first consideration, and they are assumed to be distributed to the nodes of honeycomb mesh in the second consideration. In each honeycomb structure, the fundamental linear shift‐invariant dynamics is introduced and then the stability criterion is presented.
Observability of Depth Estimation for a Hand‐Eye Robot System
Authors: Fang Chang‐Jia , Lin Shir‐Kuan 
Published: September 2010

ABSTRACTThis paper deals with the depth observability problem of a hand‐eye robot system. In contrast to earlier works, this paper presents a complete study of this observability problem. The velocity of the active camera in the hand‐eye robot system is considered as the input. The observability of depth estimation is then related to the velocity of the camera. A necessary and sufficient condition for the types of camera velocities necessary to ensure observability is found. This compensates for the results of earlier works, in which the velocity of camera was estimated. The theory is also verified by both simulations and experiments in this paper. Furthermore, a modified LQ visual servo control law is proposed to vary the weighting matrices so that depth estimation is improved while the level of control performance is still retained.
Robust Isolation Of Sensor Failures
Authors: Xu R. , Kwan C. 
Published: September 2010

ABSTRACTSensor self‐validity check is a critical step in system control and fault diagnostics. In this paper, a robust approach to isolate sensor failures is proposed. First, a residual model for a given system is built off‐line and directly based on input‐output measurement data. The residual model outputs are called “primary residuals” and are zero when there is no fault. Most conventional approaches to residual model generation are indirect, as they first require the determination of state‐space or other models using standard system identification algorithms. Second, a new max‐min design of structured residuals, which can maximize the sensitivity of structured residuals with respect to sensor failures, is proposed. Based on the structured residuals, one can then isolate the sensor failures. This design can also be done in an off‐line manner. It is an optimization procedure that avoids local optimal solutions. Simulation and experimental results demonstrated the effectiveness of the proposed method.
Torque Maximisation Of The Pmac Motor For High Performance, Low Inertia Operation
Authors: Stewart Paul 
Published: September 2010

ABSTRACTThis paper describes the techniques applied to maximise the torque envelope of the permanent magnet AC (PMAC) motor operating under current and voltage constraints. Standard steady‐state descriptions of the system are often suitable for control purposes when the rotor velocity is varying relatively slowly. In low inertia applications such as clutchless gearchange operations, where in the pursuit of driveability, the motor is required to accelerate and decelerate its own rotor inertia as quickly as possible. In this case, the voltage drop due to the current dynamics start to become significant. This paper presents a method to reserve voltage headroom dynamically in the field‐weakening region in order to maximise the torque envelope when the effective inertia is low. Experimental results show the effectiveness of this approach.
Discretization Of A Non‐Linear, Continuous‐Time Control Law With Small Control Delays
Authors: Herrmann Guido , Spurgeon Sarah K. , Edward Christopher 
Published: September 2010

ABSTRACTThis paper considers time‐discretized, non‐linear, continuous‐time control laws with small computational time‐delays. The discretized control is not initiated immediately after the sampling instant ti. Small variable computational delays ∞ are assumed to be present. Provided the sampling time ∞ is small and the maximum ratio ∞ is known, then the main theorem provides a stability result. In contrast to a former result, the theoretical framework considers robust control problems allowing a class of uncertainty and disturbances to be investigated. The different techniques are compared numerically for a discretized continuous‐time sliding‐mode based state‐feedback control.
A Parallel Block Scaled Gradient Method With Decentralized Step‐Size For Block Additive Unconstrained Optimization Problems Of Large Distributed Systems
Authors: Lin Shin‐Yeu , Lin Shieh‐Shing 
Published: September 2010

ABSTRACTIn this paper, we propose a modified parallel block scaled gradient method for solving block additive unconstrained optimization problems of large distributed systems. Our method makes two major modifications to the typical parallel block scaled gradient method: First, we include a pre‐processing step which reduces the computational time; second, we propose a decentralized Armijo‐type step‐size rule. This rule circumvents the difficulty of determining a step‐size in a distributed computing environment and enables the proposed parallel algorithm to execute in a distributed computer network with a limited amount of data transfer.We have applied our method to the weighted‐least‐square problems of power system state estimation and demonstrated the convergence of our method by testing numerous examples on a PC network. The speedup ratio of the distributed version of our method tends to increase proportionally with the number of subsystems (or computers).
Robust Stabilization Of Interval Plants With Constant Disturbance
Authors: Fernández‐Anaya G. , Alvarez‐Ramírez J. 
Published: September 2010

ABSTRACTThe aim of this brief paper is to study the output feedback, robust stabilization problem for a class of SISO interval plants with unknown constant disturbance. For interval plants of minimum phase and known high‐frequency gain, it shows that a simple controller with integral action is able to reject the disturbance. A procedure to compute the parameters of the controller is discussed.
Reliable Robust Preview Tracking Control Against Actuator Faults
Authors: Liao Fang , Wang Jianliang , Yang Guang‐Hong 
Published: September 2010

ABSTRACTIn this paper we provide a solution to the reliable robust preview tracking problem against actuator faults for discrete LTI systems with polytopic uncertainties. This solution is in terms of the solvability of linear matrix inequalities (LMIs). The method is based on multi‐objective optimization and LQ tracking performance indices. To avoid the conservativeness problem associated with using a common LMI solution for the normal case and the fault cases, different LMI solutions are used in the proposed method. Two iterative algorithms are proposed and compared. Numerical examples are used to show the effectiveness of the algorithms.
Control Routh Array And Its Applications
Authors: Cheng Daizhan , Tarn T.J. 
Published: September 2010

ABSTRACTIn this paper the Routh stability criterion [16] has been developed into control Routh array. Some formulas for calculating the array are provided. Certain properties are investigated. Using it, the problem of stabilization of bilinear systems via constant controls is solved. Then by converting the problems, the method of control Routh array is also used to solve some other stability related problems, such as the stabilization of control systems, the stability of uncertain Hurwitz matrix and the stability of interval matrices. Several algorithms have been developed to provide numerical solutions.
Reliable Decentralized Supervisory Control For Marked Language Specifications
Authors: Takai Shigemasa , Ushio Toshimitsu 
Published: September 2010

ABSTRACTWe consider a discrete event system controlled by a decentralized supervisor consisting of n local supervisors. In our previous work, we have studied reliable decentralized supervisory control for closed language specifications. In this paper, we extend this work to the specifications given by marked languages. A decentralized supervisor is said to be k‐reliable (1 ∞ k ∞ n) if it exactly achieves a specification language without blocking under possible failures of any less than or equal to n ‐ k local supervisors. We present necessary and sufficient conditions for the existence of a k‐reliable decentralized supervisor. Then we define a weaker version of k‐reliability, called weak k‐reliability, by relaxing the nonblocking requirement. We obtain necessary and sufficient conditions for the existence of a weakly k‐reliable decentralized supervisor. Moreover, we propose an iterative scheme for computing a sublanguage of a specification for which the existence conditions of a weakly k‐reliable decentralized supervisor are satisfied.
RobustH∞Control Problem For General Nonlinear Systems With Uncertainty
Authors: Wu Jenq‐Lang , Lee Tsu‐Tian 
Published: September 2010

ABSTRACTIn this paper, both state and output feedback robustH∞control problems for general nonlinear systems with norm‐bound uncertainty are considered. Sufficient conditions for the existence of robust output feedbackH∞controller are provided. State space formulas for robustH∞output controller are provided.
Fuzzy Sliding Mode Control For Ship Roll Stabilization
Authors: Chen Shyh‐Leh , Hsu Wei‐Chih 
Published: September 2010

ABSTRACTA fuzzy sliding mode controller is proposed in this study for ship roll stabilization. Ship dynamic models usually contain large uncertainty. Sliding mode control is well known for its good robustness to large uncertainty. However, the required uncertainty bound is usually difficult to estimate. A fuzzy logic is designed here for the upper bound estimation of the uncertainty coming mostly from the wave excitation. As a result, the uncertainty‐related parameters in the sliding mode controller are automatically tuned by fuzzy logic according to the encountered wave amplitude. The present controller has the advantage that smaller control efforts are required for the anti‐capsizing purpose under the same sea states. A numerical example is investigated to confirm the analysis.
Design Of Robust Pole Assignment Based On Pareto‐Optimal Solutions
Authors: Tagami Takanori , Ikeda Kenji 
Published: September 2010

ABSTRACTIn this paper, a new design method for robust pole assignment based on Pareto‐optimal solutions for an uncertain plant is proposed. The proposed design method is defined as a two‐objective optimization problem in which optimization of the settling time and damping ratio is translated into a pole assignment problem. The uncertainties of the plant are represented as a polytope of polynomials, and the design cost is reduced by using the edge theorem. The genetic algorithm is applied to optimize this problem because of its multiple search property. In order to demonstrate the effectiveness of the proposed design method, we applied the proposed design method to a magnetic levitation system.
A Stable Output Feedback Position Control With Integral Action For Robot Manipulators
Authors: Alvarez‐Ramirez Jose , Kelly Rafael , Cervantes Ilse 
Published: September 2010

ABSTRACTIn this paper, the problem of robust regulation of robot manipulators using only position measurements is addressed. The main idea of the control design methodology is to use an observer to estimate simultaneously the velocity and the modeling error signal induced by model/system mismatches. The controller is obtained by replacing the velocity and the modeling error in an inverse dynamics feedback by their estimates, which leads to a certainty equivalence controller. The resulting controller has a PID‐type structure which, under least prior knowledge, reduces to the PI2D regulator studied in [20]. Moreover, the controller is endowed with a natural antireset windup (ARW) scheme to cope with control torque saturations. Regarding the closed‐loop behavior, it is proven that the region of attraction can be arbitrarily enlarged with high observer gains only, thus we prove semiglobal asymptotic stability. Our result supersedes previous works in the direction of performance estimates; specifically, it is also proven that the performance induced by a saturated inverse dynamics controller can be recovered by our PID‐type controller. In this sense, our work reveals some connections between PID‐type and inverse dynamics controllers.
Dynamical Output Feedback Stabilization Of Mimo Bilinear Systems With Undamped Natural Response
Authors: Lu Guoping , Zheng Yufan , Zhang Cishen 
Published: September 2010

ABSTRACTThis paper considers the globally asymptotic stabilization problem of multi‐input multi‐output bilinear systems with undamped natural response. Under the conditions for asymptotic stabilization by static state feedback control and system detectability, two output dynamic feedback controllers with saturation bounded control are constructed. The global asymptotic stability of the closed‐loop system is verified by Lyapunov stability theory and LaSalle's Lemma. An example is given to demonstrate the obtained results.
Indexing Valve Plate Pump: Modeling And Control
Authors: Zhang X. , Cho J. , Nair S. S. 
Published: September 2010

ABSTRACTA reduced order dynamic modeling method, and a pressure control strategy are proposed for a novel axial variable‐displacement pump design. The reduced order model provides insights into the dynamics, and is useful for control design. Theoretical as well as implementation insights for the control problem are also developed, including proportional control limitations which provides guidance for effective control designs.
Characterisation Of Receding Horizon Control For Constrained Linear Systems
Authors: Seron María M. , Goodwin Graham C. , De Doná José A. 
Published: September 2010

ABSTRACTThis paper characterises the geometric structure of receding horizon control (RHC) of linear, discrete‐time systems, subject to a quadratic performance index and linear constraints. The geometric insights so obtained are exploited to derive a closed‐form solution for the case where the total number of constraints is less than or equal to the number of degrees of freedom, represented by the number of control moves. The solution is shown to be a partition of the state space into regions for which an analytic expression is given for the corresponding control law. Both the regions and the control law are characterised in terms of the parameters of the open‐loop optimal control problem that underlies RHC and can be computed off line. The solution for the case where the total number of constraints is greater than the number of degrees of freedom is addressed via an algorithm that iteratively uses the off‐line solution and avoids on‐line optimisation.
Determination Of The Phase Current Waveform For A Disc‐Type Axial‐Flux Wheel Motor
Authors: Yang Yee‐Pien , Luh Yih‐Ping , Pan Yann‐Guang 
Published: September 2010

ABSTRACTAn optimal design of the driving current pattern for a disc‐type axial‐flux brushless DC wheel motor of an electric vehicle is proposed in this paper. The electro‐magnetic dynamic model of the motor is established with magnetic circuits, describing the relationship between the output torque and excitation current. The optimal current pattern, in terms of magnitude and phase angle, is then obtained by maximizing the output torque with respect to the rotor shift. Compared with the traditional three‐phase‐on current pattern of fixed 120–degree phase shift, both the average torque and efficiency with the driving current of an optimal advanced switching angle are seen to be improved under various loading conditions. The motor performance with the optimal driving waveform is simulated and verified by experiments.
Time Varying Deadbeat Control Of High Order Chained Systems
Authors: Mita Tsutomu , Nam Taek Kun 
Published: September 2010

ABSTRACTA new digital control method for a time varying sampled data system called a time varying deadbeat control is proposed for the control of high order nonholonomic chained systems with drift terms. This control law has the potential to avoid excessive overshoot and prevent trajectories from getting close to the singular manifolds of the transformation needed to obtain the chained forms.
Modified Weak‐Pseudo‐Sliding Mode Controller With One Sampling Period Computation Delay
Authors: Changy Kuo‐Ming , Chen Chieh‐Li , Zhu Zhi‐Hong 
Published: September 2010

ABSTRACTIn this paper, a so‐called discrete‐time modified weak‐pseudo‐sliding mode controller with one sampling period computation delay is proposed for the system with system parameter uncertainty. In the meantime, the upper bound of the sampling period is also determined to guarantee the existence of the modified weak‐pseudo‐sliding mode along the prescribed sliding surface in the proposed discrete‐time sliding mode control system.
Robust Mrac Of A Nonautonomous Parabolic System With Spatiotemporally Varying Coefficients And Bounded Disturbance
Authors: Yang Kyung‐Jinn , Hong Keum‐Shik 
Published: September 2010

ABSTRACTIn this paper, a robust model reference adaptive control of a parabolic system with unknown spatiotemporally varying coefficients and disturbance is investigated. In the adaptive control of time‐varying plants, the derivative of a Lyapunov function candidate, which allows the derivation of adaptation laws, is not negative semi‐definite in general. Under the assumption that the disturbance is uniformly bounded, the proposed robust adaptive scheme guarantees the boundedness of all signals in the closed loop system and the asymptotic convergence of the state error near to zero. With an additional persistence of excitation condition, the parameter estimation errors are shown to converge near to zero as well. Simulation results are provided.
Pid Controller Design With Guaranteed Gain And Phase Margins
Authors: Ho Ming‐Tzu , Wang Hsing‐Sen 
Published: September 2010

ABSTRACTThis paper considers the problem of designing PID controllers that achieve the guaranteed gain and phase margin specifications for a given but arbitrary single‐input single‐output plant. Using definitions of gain and phase margins, the given specifications are translated into simultaneous stabilization of two families of polynomials. Thereafter, an extension of the results of PID stabilization to the case of complex polynomials is shown to be useful in providing a solution to this simultaneous stabilization problem. A computational characterization of all admissible PID controllers is given. This characterization for all admissible PID controllers involves the solution of a linear programming problem. An example is presented to illustrate use of the design procedure in detail.