| 其他摘要 | Space targets refer to satellites, space debris, planets, stars, comets, space stations, and so on. Rapid space targets mainly include satellites and debris which run in the medium-low orbit of the earth. There are more than 3700 satellites and 11000 space debris existing in the aerospace around the earth. Therefore, the tracking and surveillance techniques of space targets should be increased to enhance the analysis and prediction capabilities of the space environment. Compared with the radar detection, photoelectric detection has such advantages as high angular resolution, strong property of anti-electromagnetic interference, low cost, small volume, light weight, and so on. To develop new methods of space target surveillance, our research group intends to create a 53cm binocular photoelectric telescope possessing a satellite laser ranging system of optical-path-splitting. It also can cooperate with the existing 1.2m laser ranging telescope to execute the joint observation. The optical-mechanical part of the telescope is manufactured by the Nanjing Astronomical Instrument Company in Chinese Academy of Sciences, and the servo control system and optical guiding system are designed and implemented by our research group of the Yunnan Astronomical Observatory in Chinese Academy of Sciences. The telescope is required to track space targets beyond 400km away from the earth within the precision better than 10 arc-second, especially rapid targets with low orbits. The servo control system controls the telescope rack to run following the predicted orbits of space targets. While the optical guiding system (mainly the imaging system) tracks space targets and extracts real-time miss distances which are transmitted to the servo control system to correct the pointing of the telescope. The researches of this thesis, including the property analysis of space targets, the scheme design of the servo control system, the partial developments of the hardware and software for the control system, the debugging and tracking testing of the control system, the study of detection and tracking algorithms for space targets, and the preliminary engineering implementation and field testing of the optical guiding system for space targets, are all related with the 53cm binocular photoelectric telescope. In the aspect of serve control, firstly, the index and scheme of the serve control system are determined according to the motion property of space target, and the selection of critical devices is also discussed. Secondly, the control chassis is integrated and the controller is embedded developed. The controller is arranged to take charge of the real-time control, while the guiding data transmission, task management and human-computer interaction are all realized by the host computer. Then the custom communication protocol between controller and computer is formulated to solve the problems of communication delay and low timing precision of the VC++, which helps the accurate control. Additionally, the control strategies of the 2th position closed loop and mixture PID are further proposed to increase the tracking precision and anti-interference capacity. The author has taken part in the installation and debugging of the servo control system twice. The various functions are realized and the design index is fully satisfied. Under limited experiment conditions, the testings of tracking and imaging for some space targets are performed. The results of images demonstrate that the telescope can realize the stable tracking of targets. In the aspect of detection and tracking for space targets, three algorithms are proposed for the different space environments according to imaging properties of space targets. (1) For the complex space environment, the joint decision and Naive Beyse learning algorithm is proposed to detect space targets, and the duty-ratio feature is also proposed. Adopting the two-step frame, it can largely solve the interferences of CCD smear and stro |
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