Relative attitude determination for fly-around based on UKF
To solve the problem of relative attitude determination of a deputy satellite with respect to chief satellite in fly-around, unscented Kalman filter (UKF) method of relative attitude determination is presented. The minimum representation of the attitude, modified Rodrigues parameter (MRP) is adopted as the attitude representation parameter. Combination of gyro, star tracker and laser rendezvous radar are employed as the attitude sensors. The state equation of relative attitude determination is obtained with consideration of relative attitude dynamic equation. Therefore, the UKF model is constructed. Simulations are done and the comparison with that of extended Kalman filter (EKF) shows that the UKF method has a faster convergence speed and a higher estimation precision.