【作者】 李振伟；

【导师】 张涛；

【作者基本信息】 中国科学院研究生院(长春光学精密机械与物理研究所) ， 机械电子工程， 2014， 博士

【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基础、光电望远镜系统、空间目标的探测与识别、空间目标的高精度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，论文提出了一种基于恒星星图匹配的指向误差实时修正方法，实现了经轴L修正精度为2.82″，纬轴B修正精度为2.85″的指向精度，改进了光电望远镜系统静态指向误差修正模型。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。论文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。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。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。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。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，论文提出了基于Tycho-2星表的三角形星像匹配的空间目标定位方法，实现了空间目标高精度定位。实验结果表明：该定位方法处理时间优于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。论文提出了一种基于恒星星等的空间目标实时光度测量方法，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。更多还原

【Abstract】 Space objects include on-orbit spacecraft and space debris. Space debrisseverely threatens the security of on-orbit spacecraft, which idrectly changes thesurface properties of the spacecraft in their collisions, and brings seriousness andgreat harm to the normal operation of on-orbit spacecraft, resulting in failure of thespacecraft system. Optical observation for space objects plays more and moreimportant roles in space objects surveillance. In order to improve performance ofour national space objects surveillance, an in-depth study of space objectssurveillance technology will have important practical significance and applicationvalue.The survey techniques start with measurement principle, detection andidentification, precise orientation and photometry of space objects, andphotooelectric telescope, discussions are made in methods of improvementsdetecting efficiency for space objects surveillance devices and higher orientationprecision for space objects.Firstly, this paper offers some insights into photooelectric telescope system ofspace objects, which include complex optical systems, telescope mount andorientation methods, and compare the advantage and disadvantage of astronomicalorientation and shafting orientation. To solve the shortage of spherical harmonicsfunction model and basic parameters model, a new algorithm for real-timecorrection of telescopes’ pointing error is proposed, whose pointing precision of telescope is2.82″at L axle and2.85″at B axle. This algorithm has good real-timeand high precision, which can be widely applied to science and engineering field.Secondly, this paper offers some insights into the ability of detection for spaceobjects, which include the detectable stellar magnitude limits， the atmosphericextinction coefficient and the size of detectable space objects, and summarizesseveral ways to improve detecting efficiency of photooelectric telescope. Then thispaper offers some insights into astronomical digital image processing technique,which include image preprocessing, image enhancement technology, imagerestoration technology and mathematic morphology.Meanwhile, based on analysisof space objects’ motion characteristics within the visible field of the CCD chip, thefast recognition algorithm is presented and realized. Experimental results indicatethat the average processing time of fast recognition for space objects is less than10ms, which can satisfy the requirements of space objects’ surveillance, such ashigh real-time, high precision, good stability and reliability.Thirdly, based on the introduction of astronomical orientation’ fundamentals,real-time astronomical orientation of space objects is realized in the usage ofTycho-2and triangle matching algorithm. Experimental results indicate thatthe average processing time of real-time astronomical orientation for space objects isless than25ms, and the precision of real-time astronomical orientation is less than4,which can satisfy the requirements of space objects’ surveillance, such as highreal-time, high precision, good stability and reliability. In addition, to overcome loworientation precision of faint space objects, the high precision orientation algorithmof faint space objects is presented using the improved traditional astronomicalorientation method, which continuously captures3frames (the time exposure of thefirst 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 highaccuracy negative processing model of the second frame, and gets the high accuracypositioning result of the second frame. We finally realize that high accuracy positioning of faint space objects in deep space, which can further improve thedetection ability and positioning accuracy of the photoelectric telescope system.At last, photometry is one of the important missions of space objects. There isno filter system equipped in the space objects telescope, which can’t measureinformation of star magnitude for space objects. A simple and convenient algorithmfor measuring information of star magnitude is presented, which can provideinformation of star magnitude with certain range of the accuracy requirement, andan effective way for photometry of space objects.更多还原