Optimal axis selection scheme of SINS single-axis rotation modulation

The rotation modulation technology of strapdown inertial navigation system (SINS) is based on a self-calibration method, which modulates the constant drift of gyroscope and bias of accelerometer into periodic signals. And these periodic signals can be eliminated through integral calculation, so that the inertial navigation system (INS) can automatically compensate the navigation error caused by gyro drift and accelerometer bias without using external information, thereby improving the system's accuracy. Based on the single-axis rotation modulation principle, this paper also analyzes the manifestations of constant drift, installation errors, and scale factor error of gyro and accelerometer when IMU uniaxially rotating about an arbitrary axis. The optimal axis selection scheme is given to minimize the gyro and accelerometer constant drifts. The simulation and experiments are carried out, which verify the effectiveness of the proposed scheme. The conclusions can also assist the design of the optimal single-axis rotational SINS to minimize the adverse effects of gyro and accelerometer constant drifts.