空间目标光电观测技术研究

	空间目标光电观测技术研究
	李振伟
学位类型	博士
导师	张涛
	2014-07
学位授予单位	中国科学院大学
学位专业	机械电子工程
摘要	空间目标包括在轨工作航天器和空间碎片。空间碎片严重地威胁着在轨运行航天器的安全，它们和航天器的碰撞能直接改变航天器的表面性能，造成表面器件损伤，导致航天器系统故障，对航天器的正常运行带来极大的危害。光电观测技术在空间目标监视中占有重要的地位。为了提高我国空间目标探测技术水平，深入研究空间目标光电观测技术具有重要的现实意义和应用价值。论文从空间目标测量原理、光电望远镜系统、空间目标的探测与识别、空间目标的精密定位、实时天文定位和光度测量等方面入手，研究提升观测设备探测能力、提高空间目标定位精度的方法。论文深入研究了空间目标光电望远镜系统，包括光学系统、望远镜机械结构以及定位方式等，着重比较了轴系定位和天文定位的优缺点。同时，针对光电望远镜系统静态指向误差修正模型（包括球谐函数模型和基本参数模型）局限性，论文提出了一种光电望远镜指向误差实时修正方法，望远镜指向实时修正精度（RMS）是：L轴方向精度2.82″，B轴方向精度（RMS）2.85″。该方法实时性好、精度高，能够广泛地应用于科研和工程领域。在分析空间目标运动特性的基础上，论文提出了“基于约束条件的空间目标快速识别算法”——在三帧连续CCD图像上，空间目标的测量坐标成等差数列，实现了空间目标快速识别。深入研究了天文图像处理技术，包括图像预处理、图像增强技术、图像复原技术以及数学形态学。初步实测结果表明：空间目标快速识别处理时间优于10ms，满足空间目标监视技术的实时性好、稳定可靠等要求。深入分析了空间目标探测能力，包括探测星等、大气消光以及探测空间目标的大小，归纳总结了提高光电望远镜探测能力的几种途径。针对光电望远镜系统轴系定位方式不足之处，在简述天文定位基本原理的基础上，论文采用Tycho-2星表和三角形星像匹配算法，实现了空间目标实时天文定位。实验结果表明：空间目标实时天文定位处理时间优于25ms，定位精度优于4˝，能够满足空间目标监视技术的实时性好、精度高、稳定可靠等要求。针对暗弱空间目标定位精度低，改进了传统天文定位方法，论文提出了“暗弱空间目标高精度定位方法” ——连续采集三帧图像（第1及3帧图像的曝光时间短，第2帧图像的曝光时间长），计算第1及3帧图像的底片处理模型，通过内插方法计算出第2帧图像底片处理模型，从而给出第二帧图像上暗弱空间目标的高精度定位结果，实现了暗弱空间目标高精度定位，进一步提高了空间目标光电观测系统的探测能力和定位精度。空间目标光度测量也是重要观测任务之一。由于我国现有绝大多数空间目标光电望远镜系统未配置滤光片系统，无法测量空间目标的星等信息。论文提出了一种较为简便的方法——利用恒星星表中已知恒星星等信息计算出空间目标星等，可以测量出满足一定精度要求的空间目标星等信息，为空间目标的光度测量找到了一条简单而有效的途径。
其他摘要	Space objects include on-orbit spacecraft and space debris. Space debris severely threatens the security of on-orbit spacecraft, which idrectly changes the surface properties of the spacecraft in their collisions, and brings seriousness and great harm to the normal operation of on-orbit spacecraft, resulting in failure of the spacecraft system. Optical observation for space objects plays more and more important roles in space objects surveillance. In order to improve performance of our national space objects surveillance, an in-depth study of space objects surveillance technology will have important practical significance and application value.The survey techniques start with measurement principle, detection and identification, precise orientation and photometry of space objects, and photooelectric telescope, discussions are made in methods of improvements detecting efficiency for space objects surveillance devices and higher orientation precision for space objects. Firstly, this paper offers some insights into photooelectric telescope system of space objects, which include complex optical systems, telescope mount and orientation methods, and compare the advantage and disadvantage of astronomical orientation and shafting orientation. To solve the shortage of spherical harmonics function model and basic parameters model, a new algorithm for real-time correction of telescopes’ pointing error is proposed, whose pointing precision of telescope is 2.82″at L axle and 2.85″at B axle. This algorithm has good real-time and high precision, which can be widely applied to science and engineering field.Secondly, based on analysis of space objects’ motion characteristics within the visible field of the CCD chip, the fast recognition algorithm is presented and realized. Then this paper offers some insights into astronomical digital image processing technique, which include image preprocessing, image enhancement technology, image restoration technology and mathematic morphology. Experimental results indicate that the average processing time of fast recognition for space objects is less than 10ms, which can satisfy the requirements of space objects’ surveillance, such as high real-time, high precision, good stability and reliability. Meanwhile, this paper offers some insights into the ability of detection for space objects, which include the detectable stellar magnitude limits， the atmospheric extinction coefficient and the size of detectable space objects, and summarizes several ways to improve detecting efficiency of photooelectric telescope.Thirdly, based on the introduction of astronomical orientation’ fundamentals, real-time astronomical orientation of space objects is realized in the usage of Tycho-2 and triangle matching algorithm. Experimental results indicate that the average processing time of real-time astronomical orientation for space objects is less than 25ms, and the precision of real-time astronomical orientation is less than 4˝, which can satisfy the requirements of space objects’ surveillance, such as high real-time, high precision, good stability and reliability. In addition, to overcome low orientation precision of faint space objects, the high precision orientation algorithm of faint space objects is presented using the improved traditional astronomical orientation method, which continuously captures 3 frames (the time exposure of the first and third frames is short, meanwhile one of the second frame is long), calculates negative processing model of the first and third frames and leads to high accuracy negative processing model of the second frame, and gets the high accuracy positioning result of the second frame. We finally realize that high accuracy positioning of faint space objects in deep space, which can further improve the detection ability and positioning accuracy of the photoelectric telescope system.At last, photometry is one of the important missions of space objects. There is no filter system equipped in the space objects telescope, which can’t measure information of star magnitude for space objects. A simple and convenient algorithm for measuring information of star magnitude is presented, which can provide information of star magnitude with certain range of the accuracy requirement, and an effective way for photometry of space objects.
语种	中文
文献类型	学位论文
条目标识符	http://ir.ciomp.ac.cn/handle/181722/41434
专题	中科院长春光机所知识产出
推荐引用方式 GB/T 7714	李振伟. 空间目标光电观测技术研究[D]. 中国科学院大学,2014.

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