Regional pole assignment with eigenstructure robustness

The paper provides a computational procedure for a type of robust regional pole assignment problem. It allows closed-loop poles to be settled at certain perturbation insensitive locations within some prespecified regions in the complex plane. The novelty of our approach lies in the versatility of the proposed algorithm which provides a rich set of constrained subregions applicable for the assignment of individual or subsets of closed-loop poles, in contrast to other conventional regional pole assignment methods. The algorithm is based on a gradient flow formulation on a differentiable potential function which provides a minimizing solution for the Frobenius condition number of the closed-loop eigenvector matrix. A numerical example is employed to illustrate the technique. The improvement on the eigenstructure robustness is compared with different kinds of constrained region.