An apparatus includes a computation unit computing a moving velocity of a moving object (MO) by differentiation on a first angle of a first-rotation unit and a second angle of a second-rotation unit, a setting unit setting a first-angular velocity of the first-rotation unit and a second-angular velocity of the second-rotation unit as angular-velocity-instruction values when the MO falls outside a correction range, and setting the second-angular velocity and a third-angular velocity as the angular-velocity-instruction values when the MO falls within the correction range, a detection unit detecting a fourth-angular velocity and a fifth-angular velocity of the first-rotation unit and the second-rotation unit, and a control unit controlling a driving unit to eliminate a difference between the fourth-angular velocity and an angular velocity corresponding to the first-rotation unit, and controlling the driving unit to eliminate a difference between the fifth-angular velocity and an angular velocity corresponding to the second-rotation unit.