Research on Attitude Residual Error of Strapdown Inertial Navigation System Based on Gyroscope Frequency Characteristics

To address the attitude residual errors of strapdown inertial navigation system (SINS) resulting from the device characteristics of a gyroscope, a method for error prediction based on turning frequency is proposed. The error prediction models in both coning environment and large maneuvering environment were developed using the conventional attitude solution approach, incorporating the bandwidth coefficient of the gyroscope. The models offer precise error prediction, surpassing current analytical techniques. The attitude residual errors prior to and following compensation were simulated with varying frequencies, while introducing the bandwidth coefficient of the gyroscope. The coning errors of two gyroscopes with varying bandwidths under different coning frequencies were determined through experimental analysis. Subsequently, the coning errors were mitigated based on the predictions derived from the error assessment. The findings indicated a general alignment between the simulation and experimental outcomes with the theoretical model predictions. Notably, when the coning frequency surpasses the gyroscope’s turning frequency, the coning error escalates by at least two orders of magnitude. In coning environments, the high bandwidth gyroscope exhibited lesser errors compared to the low bandwidth gyroscope. Following compensation, the errors associated with various coning frequencies typically decreased by more than one-third. Additionally, in large maneuvering environment, high bandwidth gyroscope also demonstrated reduced errors relative to their low bandwidth counterpart. The error prediction method can serve as a foundation for selecting inertial components or, based on the current inertial components, can be utilized to minish coning error effectively.