1. A composite system course control apparatus comprising: target value production means for producing a target value for moving a controlled object as a reality axis by a desired amount; virtual target value production means for producing a virtual target value for moving a virtual controlled object as a virtual axis based on the reality axis; and control means for calculating a control input and a virtual control input which optimize a predetermined first evaluation function upon receiving the produced virtual target value, the produced target value, a virtual state amount from the virtual controlled object, a state amount from the controlled object, a first disturbance signal with respect to the virtual controlled object, and a second disturbance signal with respect to the controlled object, and for outputting the calculated control input and the calculated virtual control input to the virtual controlled object and the controlled object, respectively, the first evaluation function including a first or second weighting function component for evaluating a course error.