Error modulation scheme analysis of dual-axis rotating strap-down inertial navigation system based on FOG

In order to enhance the accuracy of strap-down inertial navigation system, we study the error models of each inertial sensor. Based on the error effects, the rotation modulation technique is analyzed. For the case of dual-axial rotation, the error equations are derived which are produced by bias, installation error, scale factor error and random drift of inertial sensors. This paper proposes simultaneous rotation and alternately rotation, analyzes two schemes modulation mechanism and gives two reasonable rotating axes angle velocities. The simulation result presents that both rotation schemes can effectively modulate system error, and compares the modulation performance of each scheme over every navigation error.