Error Mechanism and Self‐Calibration of Single‐Axis Rotational Inertial Navigation System

Abstract

With the rapid development of inertial technology, the rotational inertial system has been widely used for high-accuracy navigation. In addition, the single-axis rotational inertial navigation system is one of the most popular navigation systems due to its low cost. However, the fact which cannot be ignored is that although single axis rotational inertial navigation system can restrain divergence of attitude error, it cannot eliminate velocity error, which is mainly caused by the gyro misalignment and scale factor error related to rotational axis. A novel calibration method established on filter has been proposed. Position, velocity, and attitude are chosen to be the state variables. In order to estimate the gyro errors related to rotational axis, these errors must be included in the state equation. Correspondingly, zero velocity and rate of turntable are chosen to be measured. Simulation has been carried out to verify the correctness of the theory, and the real test has been performed to further demonstrate the validity of the method. By compensating the main error estimated by filter, it can be found that the accumulated errors in velocity and attitude are decreased. So, the precision of navigation is greatly improved with the proposed method.

An Improved Online Self-Calibration Method Utilizing Angular Velocity Observation for Ultra High Accuracy PIGA-Based IMU

“…In the past few decades, pendulous integrating gyroscopic accelerometer (PIGA) has become a research hot spot due to its high-end performance in the field of ultra high accuracy inertial measurement unit (IMU) [ 1 ]. The accuracy of gyroscopes has made great progress in the past few decades [ 2 ]. However, the accuracy of the accelerometer has a very high correlation between the horizontal attitude and the positioning accuracy of the inertial navigation system (INS), especially in free inertial model [ 3 ].…”