中国科学院光电技术研究所机构知识库
Advanced  
IOE OpenIR  > 光电技术研究所博硕士论文  > 学位论文
题名:
星敏感器姿态测量精度研究
作者: 张辉
学位类别: 博士
答辩日期: 2007-06-07
授予单位: 中国科学院光电技术研究所
授予地点: 光电技术研究所
导师: 袁家虎
关键词: 星敏感器 ; 星点定位精度 ; 姿态测量精度 ; 标定 ; 外场观星实验
其他题名: Study on the Attitude Determination Accuracy of the Star Sensor
学位专业: 光学工程
中文摘要: 航天测控是航天工程系统的一个重要组成部分,对航天器进行姿态测量是航天测控的基本任务之一,也是航天系统能够正常工作的基本前提。在众多的姿态敏感器中,CCD星敏感器以其精度高、重量轻、功耗低等优势,成为当前姿态敏感器的研究热点,是当今航天器上必备的姿态敏感器之一。近年来,卫星轻小型化的发展方向以及卫星姿轨控系统的自主化要求等,都对星敏感器的性能提出了更高的要求,而星敏感器的高精度要求则首当其冲地成为重中之重。本论文以CCD星敏感器为研究对象,对星敏感器的姿态测量精度这一问题展开了深入的研究。 星敏感器的精度一般从两个层面考察:一个是星敏感器的星点定位精度,是对星敏感器拍摄星图中星像点位置的测量精度,这个指标直接影响星敏感器最终的姿态精度;另一个是星敏感器的姿态测量精度,该指标是评价星敏感器精度的最终标准。论文工作便是围绕星敏感器星点定位精度和姿态测量精度展开。 为研究精度问题方便起见,论文首先对基本误差理论做了概述;对星敏感器的组成、工作原理以及CCD星敏感器的误差源做了总结及概述;对星敏感器的探测目标建立了信号模型。 从星敏感器的工作流程出发,认为影响星敏感器星点定位精度的因素主要包括星点质心细分算法误差、光学系统误差、CCD模块的噪声、AD转换的量化误差以及后续电路部分的DC/DC电源模块的噪声等。以星像点质心算法为出发点,采用了理论分析和实验测量等方法,对上述各因素对星像点质心位置计算带来的误差展开了详细的讨论。分析表明:对星敏感器星点位置影响最大的误差因素是光学系统的像差,但这部分误差可以采用软件的方法减小;其次是质心算法误差和CCD模块的噪声带来的影响;A/D转换的量化误差以及DC/DC电源模块带来的噪声对星像点位置精度影响很小。 影响星敏感器姿态测量精度的因素主要包括姿态计算算法、星点定位精度、参与姿态计算的恒星信息等。针对多参考矢量姿态计算算法,对上述各因素及其对星敏感器姿态的影响规律展开了详细的讨论。结果表明:提高星点定位精度是提高星敏感器姿态测量精度的最重要的一个手段,其次,对于16°×16°的视场,选取均匀分布在视场内的9颗星参与姿态计算,能够保证星敏感器数据处理速度的要求,并能够保证星敏感器的精度。 星敏感器精确校准是实现高精度姿态测量的重要步骤,其目的是消除或减小星敏感器系统存在的系统误差,从而保证姿态测量精度。论文提出了一种对星敏感器的主点、焦距、一阶径向畸变等参数进行标定的方法。利用星敏感器的网格实验数据,以星对角距统计偏差做为评价依据,采用最小二乘算法,对各项参数进行了标定,标定结果使得星对角距偏差减小,从而能够提高星敏感器的姿态测量精度。 利用星模拟器对星敏感器进行室内实验测量是对星敏感器进行标定和检测的重要手段,但鉴于目前实验室能力和条件所限,只有通过星敏感器外场观星实验才能对星敏感器的各项性能做出正确合理的评价。文中介绍了对研制星敏感器的精度进行外场观星实验测量的方法,并给出了实际的测量结果。
英文摘要: Space TT&C system is an important component of space system. One of the radical tasks of space TT&C system is to measure attitude of spacecraft, which is the basic premise of space system in good condition. Unlike other various attitude sensors, CCD star sensor becomes the research mainstream due to many advantages, such as high attitude accuracy, light mass and less power, and is one of the absolutely necessary attitude sensors. In recent years, satellite tends to miniaturization and autonomous, which bring forward higher request to performance of star sensors, especially attitude accuracy. The thesis explores the attitude accuracy of CCD star sensor in detail. In general, accuracy performance of star sensor has two primary aspects. One is star centroid accuracy of star sensor, which is the centroiding accuracy of star point in star map, and are the most important factors influencing the attitude accuracy of star sensor. The other is attitude calculating accuracy, which is the ultimate index evaluating the accuracy performance of star sensor. In this paper, focused on the above accuracy performance of star sensor, the work is developed detailedly. For the convenience of the following depiction, firstly the foundational error theory is described; secondly the composing, basic operational principle and the error budgets of the CCD star sensor are summarized; lastly signal model of detecting object are proposed. From the point of view of the operation of star sensor, the operation of star sensor, the main errors influencing on the centroiding accuracy of star sensor concludes the centroiding algorithm error, optics error, noise of CCD, quantization error of AD conversion and the DC/DC noise of the circuit module, etc. Based on the centroiding algorithm, with the theoretical or experimental methods, the elaborate analysis is developed. The research shows that the influence of the optical aberration on star position accuracy is the largest, and then the centroiding algorithm error and noise of CCD, and finally the error of AD conversion and DC/DC module. The attitude accuracy of star sensor depends mainly on the attitude estimating algorithm, the centroiding accuracy and the message of identified stars in the field of view. Based on the multiple reference vector attitude determination algorithmic, the above factors are presented, and their operational regular is described in detail by computer simulation. The results show that it is a good choice of improving the centroid accuracy to improve the attitude, and the latter can also be improved by identifying 9 stars distributed in full 16°×16°field of view uniformly. The precision calibration of star sensor plays an important role of achieving high –accuracy attitude measurement,and it aims to decrease the system error and ensure the precision of star sensor. A calibration scheme of calibrating some parameters, such as the principal point, focal length, distortion, of star sensor is brought forward. In the scheme, experiment data are sampled by a high accuracy 2-D axial rotating platform and a single starlight simulator, all parameters are calculated with the star angle distance statistical residual as an evaluation standard, and with the least square methods. The simulations results show that the error becomes small, and the attitude measurement precision will be improved. It is an important step to calibrate star sensor and estimate its accuracy utilizing a laboratory setup with star simulator. However at present, owing to the restricted indoor experimental capability and condition, the actual performances of star sensor can by evaluated only by the real night sky observation. In this paper, the accuracy measurement method of the developed star sensor by real night sky observation is described elaborately, and the experimental results are presented.
语种: 中文
内容类型: 学位论文
URI标识: http://ir.ioe.ac.cn/handle/181551/165
Appears in Collections:光电技术研究所博硕士论文_学位论文

Files in This Item:
File Name/ File Size Content Type Version Access License
10001_200318015101036张辉_paper.doc(8531KB)----限制开放View 联系获取全文

Recommended Citation:
张辉. 星敏感器姿态测量精度研究[D]. 光电技术研究所. 中国科学院光电技术研究所. 2007.
Service
Recommend this item
Sava as my favorate item
Show this item's statistics
Export Endnote File
Google Scholar
Similar articles in Google Scholar
[张辉]'s Articles
CSDL cross search
Similar articles in CSDL Cross Search
[张辉]‘s Articles
Related Copyright Policies
Null
Social Bookmarking
Add to CiteULike Add to Connotea Add to Del.icio.us Add to Digg Add to Reddit
文件名: 10001_200318015101036张辉_paper.doc
格式: Microsoft Word
此文件暂不支持浏览
所有评论 (0)
暂无评论
 
评注功能仅针对注册用户开放,请您登录
您对该条目有什么异议,请填写以下表单,管理员会尽快联系您。
内 容:
Email:  *
单位:
验证码:   刷新
您在IR的使用过程中有什么好的想法或者建议可以反馈给我们。
标 题:
 *
内 容:
Email:  *
验证码:   刷新

Items in IR are protected by copyright, with all rights reserved, unless otherwise indicated.

 

 

Valid XHTML 1.0!
Copyright © 2007-2016  中国科学院光电技术研究所 - Feedback
Powered by CSpace