Research On Attitude Detemination Based On Star Sensor/Gyro Integrated System

Along with the wider use of satellite, higher precision of satellite attitude is required. Satellite attitude determination technology has become the key technology of satellite. Among them, star sensor and gyro integrated attitude determination system attracts much attention for its high precision and self-surviving. However, there are some problems about the system such as heavy computing burden of algorithm, long updata time of star sensor and lack of experiment environment. To slove thoes problems, this paper makes research on star sensor and gyro integrated attitude system and designs and also relizes semi-physical experiment platform.The integrated attitude determination system is researched in two aspects of algorithm and sensors. First, the intergrated attitude determination algorithms are researched and compared. The kalman algorithm on error quaternion is chosen for its high precision and short computing time. The filter is analyzed and subtracted to reduce the computing time. The simulation result is analyzed and then influence factors of precision are discussed after simulation.Secondly, in order to short the updata time of star sensor, improve precision of the intergrated attitude determination system, a new star tracking algorithm for star sensor is proposed which exploits angle velocity information from gyro system to track the known stars and then direct star scanning and star pattern recognition. The whole calculative process of the algorithm which bases on the intergrated system is given and also the precision of predicted deviation. Compared with traditional algorithm, the new algorithm is proved to have higher tracking precision. So then the time of star scanning and star pattern recognition will be shorter.At last, under the circumstance that the research of integrated attitude determination system in china is mainly based on computing simulation, lack of experiment, a semi-physical experiment platform for the integrated attitude is designed and realized, which bases on three axies rotating plate. The experiment platform is debugged in hardware and software. A method to resolve the experimental problem of synchronization of data fusion is proposed. The integrated attitude algorithm is experimented on the semi-physical experiment platform to prove its feasibility and practicality.