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

Abstract

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.

Moving base disturbance suppression method of rotary INS based on rotation angular rate

“…The simulation parameters are set as follows: The initial latitude position of the carrier is 30° north latitude; The initial heading is due north; The ground velocity is 10 m/s; The rotary INS is the single-axis system with zp spindle; The null biases of accelerometers and gyros are 10-4g and 0.01°/h; The standard deviations of accelerometers and gyros are half of the null biases; The instrument scale errors are all 10 ppm; The instrument installation errors are all 10 . The rotation methods are all continuously rotating and turning reversely every revolution; The angular rates of 5 rotation methods are: 3°/s, 6°/s, 9°/s, 12°/s and 18°/s (6°/s is the rotation rate proposed in [1]); Suppose two angular motion statuses of the carrier:…”

“…A rotary inertial navigation system (INS) has similar frames and spindles like a gimbal INS, which only work as rotation actuators and angle transducers. The rotary INS has the same calculation procedure as a strapdown INS, and can modulate and suppress the errors of inertial instruments by rotating the inertial measurement unit (IMU) [1,2]. The rotary INS makes the errors of instruments accumulate averagely in each direction of navigation coordinate frame, thus eliminates the navigation errors through the integration of the navigation calculation.…”

Improvement of the Accuracy of the Orientation of an Object by Using a Pair of Rotating IMS

“…A new approach for eliminating the systematic errors of inertial sensors is based on using the rotational motion of the IMS's platform (Ben, 2011;Collin, 2015;Sun, 2012). An rotating inertial measurement system (RIMS) generates periodical changes in the orientation of the sensitive axis of an inertial sensors, which leads to periodical changes in the DPSE with a zero mean value (after eliminating centrifugal acceleration generated by the rotation).…”

A calibration method for rotary optical encoder temperature error in a rotational inertial navigation system

“…Rotational modulation technology enables the rotational inertial navigation system (RINS) to realize significant performance increase compared to the strapdown inertial navigation system (SINS) (Chang et al 2010, Ben et al 2011. Different to SINSs, gyroscopes and accelerometers in RINSs will rotate according to the designed rotation scheme to modulate their constant errors (Li et al 2010).…”