Analysis and Self-Calibration Method for Asynchrony between Sensors in Rotation INS

Abstract

The gyroscope, accelerometer and angular encoder are the most important components in a dual-axis rotation inertial navigation system (RINS). However, there are asynchronies among the sensors, which will thus lead to navigation errors. The impact of asynchrony between the gyroscope and angular encoder on the azimuth error and the impact of asynchrony between the gyroscope and accelerometer on the velocity error are analyzed in this paper. A self-calibration method based on navigation errors is proposed based on the analysis above. Experiments show that azimuth and velocity accuracy can be improved by compensating the asynchronies.

A Calibration Method for the Errors of Ring Laser Gyro in Rate-Biased Mode

“…In this way, the errors are defined in the same way with the non-obliquely installed IMU. In this paper, we focus on the characteristics of the RLG in rate-biased mode, so the errors of RLG in mechanically dithered mode and the errors of the accelerometer including the lever arm effect should be calibrated in advance [9,10,14]. After the calibration, the scale factor errors of accelerometers will be less than 2 ppm, the constant biases of accelerometers will be less than 5 μg the misalignments of accelerometers will be less than 2″, the residual errors of accelerometers will have little effects on the calibration of the errors of RLG in rate-biased mode.…”

“…It can work in mechanically dithered mode or rate-biased mode according to the application environment. The different working mode will cause different characteristics and there are mature methods to calibrate the errors of RLG in the mechanically dithered mode [9,10], however, there are few calibration methods to evaluate the performance of RLG in rate-biased mode, because the turntable must rotate with a high angular velocity to make the RLGs stay in rate-biased mode, in this paper, a calibration method is proposed to calibrate the errors of RLGs in rate-biased mode, what is more, a ARW calculation method of RLG in rate-biased mode is also proposed. The RLGs tested in the paper are custom devices.…”

An Improved Online Fast Self-Calibration Method for Dual-Axis RINS Based on Backtracking Scheme

“…Rotational inertial navigation systems (RINS) have reached high accuracy of navigation in recent years [1,2]. A RINS consists of three gyroscopes, three accelerometers, and one rotational table.…”