부산대학교 도서관

In a high-precision ring laser gyro (RLG) inertial navigation system (INS), the g-sensitive misalignment caused by external acceleration represents one of the main error sources except for the conventional inertial measurement unit (IMU) errors (e.g., gyro drift, accelerometer bias, installation error, and scale factor error) and, thus, cannot be ignored. However, in related literature, there have been no effective suppression methods for the g-sensitive misalignment. To solve this shortcoming, this article proposes an innovative dual-axis rotation modulation navigation scheme to suppress the velocity and position errors caused by the g-sensitive misalignment, as well as conventional IMU errors. First, an error model of the g-sensitive misalignment is constructed. Then, this model is used to analyze the error propagation law of the g-sensitive misalignment in a conventional dual-axis rotation scheme. Further, based on the error propagation characteristics of each error source, the design principles of rotational modulation schemes are defined. Moreover, a 32-position dual-axis rotational modulation scheme is designed to reduce all errors, including the g-sensitive misalignment in RLG INSs. The effectiveness of the proposed rotation scheme is verified by simulations and experiments. The laboratory experimental results show that the navigation accuracy of the proposed method in this article is improved by 29.8% and 28.3% compared to the conventional 16-position scheme and 64-position scheme, respectively. The in-vehicle experiments show that the proposed method improves the accuracy by 32.7% over the 64-position scheme. The results indicate that the g-sensitive misalignment suppression is necessary in the RLG INS long-endurance autonomous navigation, and a reasonable rotational modulation scheme can effectively improve navigation accuracy.