Solving robust control problems using robust pole placement in a disk

The problem of robust pole placement in a specific disk is solved for uncertain polynomials having uncertain degree. This particular problem is used for enhancing the results of many robust control problems based on Hurwitz invariability such as robust stabilizability of uncertain systems via static state feedback, robust asymptotic command tracking, robust PID design, etc.. The present results are successfully applied to control the pressure of a variable displacement hydraulic pump having uncertain leakage flow coefficient through asymptotic command tracking.