Research on error modulating of SINS based on single-axis rotation

To weaken the influence of constant bias of inertial components on navigation precision of strap-down inertial navigation system (SINS), the error modulation method which utilizes the IMU four-position indexing is proposed in this paper. In addition, the main error source (constant drift of gyro and zero bias of accelerometer) of single axis rotating system is mainly analysed. In this new scheme, the errors of inertial sensors are modulated into periodically varied signal, as a result, the divergence of SINS errors is suppressed in long time operation. The navigation error is compared with no rotary manner via simulation. Analyses and simulation test show that the effect of the constant bias of sensors can be eliminated effectively, thus the accuracy of attitude and positioning can be greatly enhanced.