Effect of Rotation Rate Change of Rotary MIMU On System Navigation Accuracy

Inertial navigation relies on the measured angular rate and acceleration, and thus, errors in the inertial sensors can lead to inaccurate results for the navigation solution. The rotary modulation technique (RMT) can suppress the effect of inertial sensor bias, and it has thus been widely studied. Several studies have focused on the application of single-axis reciprocating rotation to micro-electromechanical-system inertial measurement units (MIMU) to improve the accuracy of the MIMU navigation solution. This scheme involves the values of the commutation angular acceleration and the angular rate of rotation, which also affects the effectivity of the RMT. However, only a few studies have carefully analyzed this issue. In this study, the authors theoretically analyze the error characteristics of MIMU reciprocating rotation, as well as the effect of angular rate and commutation angular acceleration on the effectivity of the RMT. The results indicate that the RMT can significantly improve the accuracy of MIMU navigation solution; however, the angular velocity and commutation angular acceleration considerably influence the navigation accuracy of the system.