A Calibration and Error Analysis Method for IMU Using Centrifuge

In conventional calibration of inertial measurement unit (IMU), sufficient signal excitation according to accelerometer's measuring range cannot be provided, moreover, current centrifuge-based calibration method doesn't take the IMU's orientation error on centrifuge into consideration. In this paper, a calibration and error analysis method for IMU using centrifuge was proposed. The IMU was installed on centrifuge in six positions and rotates with centrifuge in horizontal plane. Both angular velocity and acceleration excitations were provided by centrifuge. After revolution integration of the IMU's output equations, harmonic components brought by rotation of the earth and non-levelness of centrifuge can be eliminated, thus the IMU's output equation can be acquired, according to which error parameters including scale factor, misalignment, bias and orientation error can be calculated. In case of ideal horizontal installation of the IMU on centrifuge, linear least squares method was used; when taking orientation error into consideration, Newton method was used. Both the control model of centrifuge and the error propagation model were developed. Finally both models were simulated. Experiment results indicated that this calibration method was simple to implement, the input excitation can be modified, and the calibration error can be controlled.