Research on Angle Random Walk Suppression and Error Estimation and Compensation Method Based on Online Weight Distribution of Multi-RINSs

Rotary inertial navigation system(RINS) can suppress constant and slowly varying errors of inertial sensors through rotary modulation technology. However, the angle random walk(ARW) error of gyro can not be modulated, which has become the key factor of restricting the long-term navigation accuracy of RINS. In this paper, the influence of ARW on long-term navigation accuracy of RINS is analyzed. In view of the situation that GPS and other external auxiliary information are not available, an ARW suppression and error estimation and compensation method based on online weight distribution of multi-RINSs is proposed. Considering the disturbance of deflection to attitude and the disturbance of lever arm effect to velocity, the dynamic weighted average of position information of multi-RINSs are selected as the measurement, the equivalent error parameters of each RINS are estimated and compensated by KF filter is proposed. The simulation results show that the navigation errors caused by ARW can be reduced several times by using the proposed suppression method, and the weighted average position information to estimate and compensate the equivalent error of each RINS, which can further improve the navigation accuracy of each RINS by about 3 times, and proved that the proposed method of restraining ARW and error estimation and compensation is effective. It makes the relationship among the RINSs of from backup to auxiliary, which has significant value for further improving the autonomous long-term navigation accuracy.