Determined Based On The Star Pattern Recognition Algorithms In The Star Sensor And Spacecraft Attitude Research

Star sensor, also called star tracker, is a very high accuracy instrument for attitude determination. In the past thirty years, two generations of star sensors have been developed. Because the second generation star sensor has no attitude accumulation error, high pointing accuracy, fast fault-comeback ability, and completely self-determination guidance capability, it draws lots of attention. It is becoming the prior choice of the attitude measurement instruments for the current spacecrafts and the future ones.In practice, there are two key technology problems needed to be solved about the star sensor. The one is star pattern recognition problem, the other is spacecraft attitude determination (estimation) problem based on CCD star sensor. The dissertation takes the application of a star sensor in military area as background, and systematically studies and solves the above two key technology problems of the star sensor in practice.The dissertation is composed of three parts. The first part is the preface and some background knowledge, including the task source, study background, the reason to select the task, the current status in this area at home and abroad, the principle works and contribution in the dissertation, the dissertation's general configuration, some astronomical background knowledge, CCD device, and the definition of CCD star sensor coordinate system.In the second part one of the two key technology problems, star pattern recognition algorithms, is studied. The star map pre-treatment is introduced. It sums and compares all existing star pattern recognition algorithms, and presents some valueable conclusions. It proves the robustness of a star pattern recognition algorithm based on singular value decomposition. The physical explanation for the robustness of the algorithm is presented. The simulation experiment results show that the algorithm is robust. So the foundation of the star pattern recognition algorithm based on singular value decomposition to be used widely is established. Star pattern recognition algorithms for the partial celestial sphere is of important and have high value in military area. So the star pattern recognition algorithms for the partial celestial sphere are studied systematically and presented. A new star pattern recognition algorithm for all-sky isput forward. The star pattern recognition algorithm is proved to have favorable performance by simulation experiments. Its adaptability is analyzed and is fully validated. The star pattern recognition algorithm can be used to guide spacecrafts in complete self-determination manner.The other key key technology problems, spacecraft attitude determination/estimation algorithms based on star sensor, is studied in the third part. The attitude stabilization modes of a spacecraft are introduced briefly. All kinds of attitude representations for a spacecraft are summarized. A spacecraft attitude determination model based on the CCD star sensor is built. The usage of different star patterns on a spacecraft is introduced. The static attitude determination algorithms based on CCD star sensor for the spacecraft are investigated. All the static attitude determination algorithms are compared with each other by an instance. At the end three dynamic attitude estimation algorithms based on CCD star sensor are studied in detail. The simulation experiment results show that the theoretical analysis about these algorithms is correct.The last chapter includes the summarization of the dissertation, the innovations, and the recommendations for future work.