6 papers
Fast optimization of viscosities for frequency-weighted damping of second-order systems
Nevena Jakovcevic Stor, Tim Mitchell, Zoran Tomljanovic +1
We consider frequency-weighted damping optimization for vibrating systems described by a second-order differential equation. The goal is to determine viscosity values such that eig…
Fast Interpolation-based Globality Certificates for Computing Kreiss Constants and the Distance to Uncontrollability
Tim Mitchell
We propose a new approach to computing global minimizers of singular value functions in two real variables. Specifically, we present new algorithms to compute the Kreiss constant o…
Computing the Kreiss Constant of a Matrix
Tim Mitchell
We establish the first globally convergent algorithms for computing the Kreiss constant of a matrix to arbitrary accuracy. We propose three different iterations for continuous-time…
A Comparison of Nonsmooth, Nonconvex, Constrained Optimization Solvers for the Design of Time-Delay Compensators
Vyacheslav Kungurtsev, Tim Mitchell, Tomas Vyhlidal
We present a detailed set of performance comparisons of two state-of-the-art solvers for the application of designing time-delay compensators, an important problem in the field of…
Low-Order Control Design using a Reduced-Order Model with a Stability Constraint on the Full-Order Model
Peter Benner, Tim Mitchell, Michael L. Overton
We consider low-order controller design for large-scale linear time-invariant dynamical systems with inputs and outputs. Model order reduction is a popular technique, but controlle…
Approximating the Real Structured Stability Radius with Frobenius Norm Bounded Perturbations
Nicola Guglielmi, Mert Gurbuzbalaban, Tim Mitchell +1
We propose a fast method to approximate the real stability radius of a linear dynamical system with output feedback, where the perturbations are restricted to be real valued and bo…