Patent US 7,123,973

A method for controlling a controlled process in response to an input signal and a disturbance signal includes modeling the controlled process in a process model; controlling the process model by a first controller; isolating the first controller from the disturbance signal so that the first controller may be designed for an optimal response to the input signal; driving the first controller by a first drive signal proportional to the difference between the input signal and a process model output signal; isolating a second controller from the input signal so that the second controller may be designed for an optimal response to the disturbance signal; and driving the second controller by a second drive signal proportional to difference between a process output signal and the process model output signal.