Satellites In Geosynchronous Orbit Tolerant Attitude Determination Of Orbit Determination Study

The satellite intelligent autonomous control technologies without gyroscope possess a lot of merits: (1) Enhancing system's effective load; (2) Reducing the running cost of satellite during orbiting; (3) Doing system's backup in system with gyroscope; (4) Enhancing system's reliability. Many countries all go on extensive research in this field at present. American has the most advanced technology and it has succeeded in satellite applications. Our country's technology comparing with that of overseas in this aspect has yet existed biggish difference. In this situation, this thesis, taking geosynchronous satellite as researching object, systemic studies the multi-sensor information fusion technology, fault diagnosis techniques and system rebuild technology in satellite attitude control system without gyroscope, studies autonomous navigation technology in aspect of satellite orbital determination.The main efforts done in this thesis are as follows:1. The research on the multi-sensor information fusion technologies in satellite without gyroscope. At first, three kinds of attitude sensors (CCD, DES and DSS) are used to build in three independent subsystems of attitude determination. Afterward, the decentralization filter is built to go on multi-sensor information fusion, which makes the whole system satisfy the high-precision, real time and few calculation requirements. Numerical simulation is done for thoroughly analyzing system's performance. At last simulation results are analyzed.2. The research on fault diagnosis and system rebuild technology in satellite control system. After analyzing characteristic of attitude determination system and classify of failure, fault diagnosis method with weighted sum-squared residual (WSSR) is used in fault ego diagnosis of satellite attitude system. Characteristic of system model are took full advantage of, which make a case happen that realize system rebuilt without increasing algorithmic complex degree.3. The research on geosynchronous satellite autonomous navigation technology. The starlight angle method is used in orbital determination of high-orbit satellite. Through comparing EKF (Extended Kalman Filtering) with UKF (Unscented Kalman Filtering), the results show that UKF can remarkably improve orbit precision of starlight angle method and is a kind of effective method dealing with filtering of strong nonlinear system.The innovations of this thesis are as follows: The attitude and orbit determination of satellite use the same sensor. All navigation information can be gained without gyroscope. The algorithms of fault diagnosis and system rebuild are very simple and utility. Successful using UKF algorithm, which deals with the strong nonlinear problem of orbital determination in the starlight angle method, makes system to belong to better performance.