POLYNOMIAL SOLUTION OF THE STANDARD H(INFINITY)CONTROL PROBLEM FOR STRIP MILL GAUGE CONTROL

A solution to the standard H-infinity optimal control problem is prese nted which is particularly useful in machine control applications wher e the output to be controlled is different from the signal for feedbac k. The solution is obtained in polynomial form and the plant structure which is assumed represents a range of applications in the manufactur ing and process industries. The results are applied to the design of a thickness-control system for cold-rolling mills subject to a range of disturbance noise inputs.