Application of Frequency-Following Servocompensator to Unbalance Compensation in Gyro With Flexures Gimbal

A frequency-following servocompensator is applied to a rotary gyro with flexures gimbal to eliminate the oscillating components from the estimated signals. In the targeted gyro, a synchronous motor is fixed to a rectangular holder and a disk-type rotor is driven by the motor to generate gyroscopic couplings. The coupled two rotational motions of the holder are controlled by four electromagnets on the stator; the angular velocities are estimated from the control currents to regulate the relative displacement of the holder to the stator. The other four-degree-of-freedom motions of the holder are constrained by the flexures gimbal. Such suspension using flexures makes the system less damped so that high accuracy is expected to this gyro. However, one of the problems is that an oscillating component caused by rotor unbalance appears in the estimated signal because the estimation is based on the control input. To solve this problem, the frequency-tracking servocompensator is applied to eliminate the oscillating component. The virtually perfect elimination of the component from the estimated signal was achieved.