Fast heading-rotation-based high-accuracy misalignment angle estimation method for INS and GNSS

When an inertial navigation system (INS) is used to evaluate the performance of an attitude determination system (GADS) based on the global navigation satellite system, the misalignment angles between them should be estimated correctly. The traditional misalignment angle estimation method treats the average attitude differences between GADS and INS as misalignment angles. Hence, the east and north components (levels) of the attitude errors caused by the accelerometer errors are mistakenly treated as misalignment angles. In this study, the level attitude error model is built considering the accelerometer errors. Furthermore, a fast and highly accurate misalignment angle estimation method based on heading-rotation is proposed to estimate the level attitude errors and misalignment angles simultaneously. This proposed method is examined through a turntable test. Experiment results demonstrate the capability of the proposed method in estimating the misalignment angles between high-accuracy GADS and INS.