Research on error online correction technology for airborne SINS/EODS-integrated navigation system

Purpose To address the navigation challenges where the global satellite navigation system is unreliable or unavailable, an online error correction method for airborne strap-down inertial navigation system (SINS)/electro-optical detection system (EODS)-integrated navigation is proposed in this study. Traditional SINS/EODS-integrated navigation system often ignores the EODS positioning errors caused by the attitude errors of SINS and the mounting angles between the SINS and EODS. This study aims to enhance navigation performance by correcting these errors in real time. Design/methodology/approach In this method, the EODS mounting angle errors are augmented as state variables and introduced into the measurement equations together with the SINS attitude errors. After obtaining the error state optimal estimates by filtering calculation, the SINS navigation solutions and EODS mounting angles are corrected in real time. In addition, the functional relationship between the filtered measurement noise and EODS distance and angle measurement errors is derived, and an accurate measurement noise covariance matrix model is established. Findings The simulation results show that the proposed method can accurately estimates the EODS mounting angles in real time, with estimation error reduced to approximately 1/10 of the original values. Compared with traditional method, the navigation accuracy is significantly improved by approximately 90%. Originality/value This method provides a global satellite navigation system-independent SINS/EODS-integrated navigation system, reducing the impact of SINS attitude errors on the positioning accuracy of EODS and estimating the EODS mounting angles in real time.