Simultaneous stabilization of linear single-input systems by linear state feedback control

A necessary and sufficient condition for the existence of a linear state feedback controller which will simultaneously stabilize a finite collection of single-input linear systems is presented. This condition can be checked numerically through the solution of a non-linear programming problem presented here and can be used to determine whether or not a particular simultaneous stabilization problem has a solution. If the stabilization problem has a solution, the method provides a means of constructing a suitable controller. The proposed method is very versatile. It is a simple matter to limit the size of elements of the feedback gain vector and thus ensure that the control action is not excessive. In addition, for simultaneous stabilization problems which have a range of possible solutions, the proposed method makes it possible to select one which yields good performance.