Aerospace Instrument-Making Annotation << Back The algorithms for spacecraft attitude and angular rate estimation from star sensor measurements Solovyev I.V. This paper presents a novel algorithmic system designed to provide the spacecraft attitude and angular rate estimates from star sensor measurements. The system includes a lost-in-space star identification algorithm, a batch attitude estimation algorithm, and Kalman filter generating the estimates of the attitude quaternion and angular velocity vector. The proposed system enables autonomous attitude and angular rate estimation in cases when gyros measuring the angular velocity vector are either out of order or absent. The star identification algorithm is based on the well validated «Pyramid» algorithm but includes some enhancements. The batch attitude estimation algorithm uses the approximate solution to the Wahba problem providing very fast attitude quaternion determination. This quaternion is then used as the input to 7-state Kalman filter which computes the more accurate filtered quaternion and the angular velocity vector. Presented results of numerical tests demonstrate the efficiency of the proposed algorithms and their robustness to measurement and process noises. The proposed system should increase the relia-bility of space missions making it possible to estimate the full state of spacecraft rotating motion in cases of gyros’ failures. Key words: stars identification, attitude determination, star sensor, Kalman filtering. Contacts: E-mail: i.solovieff@yandex.ru Pp. 10-27.