Line of Sight Angular Rate Estimation Based on Robust Cubature Kalman Filter with Standard Trajectory Uncertainties

Aiming at the problem that inertial measurement element is not suitable for low-cost guided ammunition, a method for estimating the line of sight (LOS) angular rate of missile motion parameters instead of inertial measurement element is designed. Based on the missile target motion model and seeker measurement model, a LOS angular rate filtering model is constructed. Aiming at the characteristics of nonlinearity and parameter uncertainty of the model, robust cubature Kalman filter (RCKF) is proposed to transform the filtering problem of the uncertain filtering model into the problem of minimizing the upper bound with parameter error covariance. Compared with the cubature Kalman filter (CKF), the effectiveness and robustness of RCKF were verified by digital simulation. The experimental results showed that RCKF was effective and its accuracy was slightly better than CKF under the condition of small disturbance; Under the condition of large disturbance, the maximum error of LOS inclination angle decreased by 55.56%, the standard deviation decreased by 55.53%. The maximum error of LOS deflection angle decreased by 56.5%, the standard deviation decreased by 55.51%. The maximum error of LOS inclination angle rate decreased by 53.92%. The standard deviation decreased by 55.96%. The maximum error of LOS deflection angle rate decreased by 55.57%, the standard deviation decreased by 55.41%.