Robust polynomial pole assignment with stable controller

Stable dynamical controller design and system robustness improvement by polynomial pole assignment are considered. Based on a generic controller form for polynomial pole assignment, a formulation of stable dynamical controllers is proposed. The robustness function in the frequency domain which is used in H^∞ robust control design is minimised using the freedom provided by polynomial pole assignment. It is also shown how to combine time-domain performance specifications provided by pole assignment and robust performance specifications in the frequency domain considered by H^∞ control to realise joint optimum robustness