Abstract A method for calibration of strapdown inertial navigation systems (SINS) is proposed which combines the advantages of the approached based on the application of the Kalman filter, on the one hand, and estimates of changes in specific force in the horizon plane before and after rotation of the turntable, on the other. In contrast to the known methods of SINS calibration that take into account the changes in the horizon components of acceleration with a model measurement matrix in iterative calculations of corrections to biases, scale factors, and misalignments of accelerometers and gyroscopes (hereinafter called gyros), the approach described in this paper uses actual rotations and positions of the SINS with account for previous iterations rather than SINS uniaxial rotation angles and positions specified to a turntable. The same experimental data were used to compare the proposed method with the one using the model measurement matrix. The results have shown that the overall error of the SINS calibrated by the proposed method is less than in the other case; in addition, the number of required iterative refinements is less. The proposed method allows navigation-grade SINS to be calibrated on low-accuracy turntables, with proper consideration for the inaccuracy of the SINS inertial measurement unit (IMU) rotation in shock absorbers.
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