6. 1 Open-and Closed-loop Disturbance Rejection Open-loop control system with disturbance D D RR G1○G, D C=GG2R+G2D=CDesired +ACO Open When r=o, CoD.(ACOpen=g,Do D)6.1 Open- and Closed-loop Disturbance Rejection • Open-loop control system with disturbance D: R R C D G1 G2 H C D C = G1 G2 R + G2 D = CDesired + COpen 0, . ( ) When R = C  D COpen = G2 D  D