New Methods for Estimating the Distance to Uncontrollability
Ming Gu · SIAM Journal on Matrix Analysis and Applications · 2000
Controllability is a fundamental concept in control theory. Given a linear control system, we present new algorithms for estimating its distance to uncontrollability, i.e., the norm of the normwise smallest perturbation that makes the given system uncontrollable. Many algorithms have been previously proposed to estimate this distance. Our new algorithms are the first that correctly estimate this distance at a cost polynomial in a dimension of the given system. We report results from some numerical experiments that demonstrate the reliability and effectiveness of these new algorithms.