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Closed-loop Poles (closed-loop + pole)

Distribution by Scientific Domains
Engineering100%

Selected Abstracts

Active tendon control of cable-stayed bridges: a large-scale demonstration

EARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 7 2001
Frédéric Bossens
This paper presents a strategy for active damping of cable structures, using active tendons. The first part of the paper summarizes the theoretical background: the control law is briefly presented together with the main results of an approximate linear theory which allows the prediction of closed-loop poles with a root locus technique. The second part of the paper reports on experimental results obtained with two test structures: the first one is a small size mock-up representative of a cable-stayed bridge during the construction phase. The control of the parametric vibration of passive cables due to deck vibration is demonstrated. The second one is a 30 m long mock-up built on the reaction wall of the ELSA test facility at the JRC Ispra (Italy); this test structure is used to demonstrate the practical implementation of the control strategy with hydraulic actuators. Copyright © 2001 John Wiley & Sons, Ltd. [source]

LMI approach to reliable guaranteed cost control with multiple criteria constraints: The actuator faults case

INTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL, Issue 8 2009
Dengfeng Zhang
Abstract Based on the multi-objective optimization strategy and linear matrix inequality approach, the problem of reliable guaranteed cost control with multiple criteria constraints is investigated for a class of uncertain discrete-time systems subject to actuator faults. A fault model in actuators, which considers outage or partial degradation in independent actuators, is adopted. The quadratic stability is proved to be independent of the disturbance and the upper bound of a quadratic cost index is improved. The reliable feedback controller is designed to minimize the upper bound of the quadratic cost index, place all the closed-loop poles in a specified disk, constrain the H, norm level of the disturbance attenuation into a given range and guarantee the magnitudes of control inputs less than the given bound, as well. Thus, the resulting closed-loop system can provide satisfactory stability, transient behavior, disturbance rejection level and optimized upper bound of the quadratic cost performance despite possible actuator faults. Copyright © 2008 John Wiley & Sons, Ltd. [source]

Gain Scheduled LPV H, Control Based on LMI Approach for a Robotic Manipulator

JOURNAL OF FIELD ROBOTICS (FORMERLY JOURNAL OF ROBOTIC SYSTEMS), Issue 12 2002
Zhongwei Yu
A new approach to the design of a gain scheduled linear parameter-varying (LPV) H, controller, which places the closed-loop poles in the region that satisfies the specified dynamic response, for an n -joint rigid robotic manipulator, is presented. The nonlinear time-varying robotic manipulator is modeled to be a LPV system with a convex polytopic structure with the use of the LPV convex decomposition technique in a filter introduced. State feedback controllers, which satisfy the H, performance and the closed-loop pole-placement requirements, for each vertex of the convex polyhedron parameter space, are designed with the use of the linear matrix inequality (LMI) approach. Based on these designed feedback controllers for each vertex, a LPV controller with a smaller on-line computation load and a convex polytopic structure is synthesized. Simulation and experiment results verify that the robotic manipulator with the LPV controller always has a good dynamic performance along with the variations of the joint positions. © 2002 Wiley Periodicals, Inc. [source]

Controller design for optimal tracking response in discrete-time systems

OPTIMAL CONTROL APPLICATIONS AND METHODS, Issue 5 2007
O. A. Sebakhy
Abstract The problem of designing a controller, which results in a closed-loop system response with optimal time-domain characteristics, is considered. In the approach presented in this paper, the controller order is fixed (higher than pole-placement order) and we seek a controller that results in closed-loop poles at certain desired and pre-specified locations; while at the same time the output tracks the reference input in an optimal way. The optimality is measured by requiring certain norms on the error sequence,between the reference and output signals,to be minimum. Several norms are used. First, l2 -norm is used and the optimal solution is computed in one step of calculations. Second, l, -norm (i.e. minimal overshot) is considered and the solution is obtained by solving a constrained affine minimax optimization problem. Third, the l1 -norm (which corresponds to the integral absolute error-(IAE)-criterion) is used and linear programming techniques are utilized to solve the problem. The important case of finite settling time (i.e. deadbeat response) is studied as a special case. Examples that illustrate the different design algorithms and demonstrate their feasibility are presented. Copyright © 2007 John Wiley & Sons, Ltd. [source]

ROBUST OUTPUT FEEDBACK CONTROLLER DESIGN WITH COVARIANCE AND DISC CLOSED-LOOP POLE CONSTRAINTS

ASIAN JOURNAL OF CONTROL, Issue 3 2005
Li Yu
ABSTRACT This paper is concerned with the problem of robust output feedback controller design for a class of linear discrete-time systems with normbounded uncertainty. The objective is to design a controller such that the closed-loop poles are assigned within a specified disc and the steady regulated output covariance is guaranteed to be less than a given upper bound. Using a linear matrix inequality (LMI) approach, the existence conditions of such controllers are derived, and a parametrized characterization of a set of desired controllers (if they exist) is presented in terms of the feasible solutions to a set of LMIs. A procedure is given to select a suitable output feedback controller that minimizes the desired control effort. [source]