Organizational Unit:
Wallace H. Coulter Department of Biomedical Engineering
Wallace H. Coulter Department of Biomedical Engineering
Permanent Link
Research Organization Registry ID
https://ror.org/02j15s898
Description
Previous Names
Parent Organization
Parent Organization
Organizational Unit
Includes Organization(s)
ArchiveSpace Name Record
Publication Search Results
Now showing
1  10 of 26

ItemSpectral radius interpolation and robust control(Georgia Institute of Technology, 198912) Bercovici, Hari ; Foias, Ciprian ; Tannenbaum, Allen R.In a previous paper (1987) Tannenbaum discussed an interpolation problem closely related to the multivariate gain margins of J.C. Doyle (1984) and M.G. Safonov (1980). For this interpolation problem, it is necessary to interpolate on the disk with analytic matrices of bounded spectral radius instead of norm.

ItemRobust control design for a flexible beam using a distributedparameter H∞method(Georgia Institute of Technology, 198912) Lenz, Kathryn ; Özbay, Hitay ; Tannenbaum, Allen R. ; Turi, Janos ; Morton, BlaiseA skew Toeplitz theory is used to derive the H∞optimal controller for a weighted mixed sensitivity design for a freefree EulerBernoulli beam. On the basis of the structure of the optimal controller, loworder, suboptimal, finitedimensional, linear, timeinvariant controllers are designed for the beam with and without a pure time delay.

ItemControl of SlowlyVarying Linear Systems(Georgia Institute of Technology, 198912) Kamen, Edward W. ; Khargonekar, Pramod P. ; Tannenbaum, Allen R.State feedback control of slowly varying linear continuoustime and discretetime systems with bounded coefficient matrices is studied in terms of the frozentime approach. This study centers on pointwise stabilizable systems. These are systems for which there exists a state feedback gain matrix placing the frozentime closedloop eigenvalues to the left of a line Re s=γ<0 in the complex plane (or within a disk of radius ρ<1 in the discretetime case). It is shown that if the entries of a pointwise stabilizing feedback gain matrix ar continuously differentiable functions of the entries of the system coefficient matrices, then the closedloop system is uniformly asymptotically stable if the rate of time variation of the system coefficient matrices is sufficiently small. It is also shown that for pointwise stabilizable systems with a sufficiently slow rate of time variation in the system coefficients, a stabilizing feedback gain matrix can be computed from the positive definite solution of a frozentime algebraic Riccati equation.

ItemOn approximately optimal H∞ controllers for distributed systems(Georgia Institute of Technology, 198912) Özbay, Hitay ; Tannenbaum, Allen R.The structure of all approximately optimal H∞ controllers for stable distributed plants with rational weights is elucidated. The finite and infinitedimensional parts of these H ∞ controllers are identified. It is shown that one can obtain a finitedimensional approximately optimal controller by appropriately approximating the infinitedimensional part of the optimal controller. Also, it is possible to find certain bounds on the deviation from optimal performance using this procedure.

ItemA solution to the standard H∞ problem for multivariable distributed systems(Georgia Institute of Technology, 198912) Özbay, Hitay ; Tannenbaum, Allen R.The authors summarize the results of previous work in which they studied the problem of the H∞ optimal control of multivariable distributed systems in the fourblock setting. The skew Toeplitz framework is employed.

ItemOn the Nonlinear Mixed Sensitivity Problem(Georgia Institute of Technology, 198912) Foias, Ciprian ; Tannenbaum, Allen R. ; Enns, Dale ; Georgiou, Tryphon T. ; Jackson, Michael ; Schipper, BrianThe nonlinear H∞ synthesis theory for the sensitivity minimization problem is extended to the twoblock mixed sensitivity method. The synthesis method is valid for majorizable input/output operators and can be extended to operators that can be approximated by them. In particular, operators that are analytic in a ball around the origin in a complex Hilbert space are considered. It turns out that it is possible to express each nlinear term of the Taylor expansion of such an operator on a certain tensor space. In the development of the theory, some of the Toeplitz techniques are extended to linear operators defined on certain tensor spaces.

ItemA strong Parrot theorem(Georgia Institute of Technology, 198907) Foias, Ciprian ; Tannenbaum, Allen R.In this note we discuss a strengthened version of a theorem due to Parrott [8] in operator dilation theory. We relate our result to the onestep extension procedure of AdamjanArovKrein [1].

ItemWeighted Optimization Theory for Nonlinear Systems(Georgia Institute of Technology, 198907) Foias, Ciprian ; Tannenbaum, Allen R.In this paper, the solution of a nonlinear version of the weighted sensitivity H∞optimization problem is discussed. It is shown that the natural object to be considered in this context is a certain "sensitivity operator," which will be optimized locally in a given "energy ball" (see §5 for the details). In the linear case, the authors are reduced again to the classical sensitivity minimization technique of Zames [21]. The methods were very strongly influenced by the complex analytic power series ideas of [3], [4], [5]. See also the recent results of Ball and Helton [6] for another approach to this subject.

ItemRemarks on H∞ optimization multivariate distributed systems(Georgia Institute of Technology, 198812) Foias, Ciprian ; Özbay, Hitay ; Tannenbaum, Allen R.The results of a study of H∞optimization for multivariable distributed systems are summarized. A skew Toeplitz framework has been used. The problem has been reduced to finding the singular values of a certain operator (the socalled fourblock operator). Depending on the specific problem considered, the corresponding fourblock operator can be simplified to a twoblock or oneblock operator. This is specialized to the multivariate twoblock case. A procedure for the computation of the eigenvalues of this operator is described.

ItemThe four block problem for distributed systems(Georgia Institute of Technology, 198812) Foias, Ciprian ; Tannenbaum, Allen R.A study is made of the singular values of the fourblock operator, which appears naturally in many H∞ control problems. Following the framework of the monograph of B.A. Francis (1987), almost all such robust design problems can be formulated in terms of the spectral properties of such an operator. This includes the problems of sensitivity and mixedsensitivity minimization, model matching, and certain tracking problems. The authors' techniques give the optimal solution to this problem, which is valid for a large class of distributed systems.
 «
 1 (current)
 2
 3
 »