【作者】 孙守明；

【导师】 汤国建； 郑伟；

【作者基本信息】 国防科学技术大学 ， 航空宇航科学与技术， 2011， 博士

【摘要】 自主导航是提高航天器自主运行能力的关键,是制约我国航天事业发展的主要瓶颈技术之一。论文以提高航天器的自主导航能力这一重大需求为牵引,围绕X射线脉冲星导航中尚未解决的关键技术问题,系统地研究了基于X射线脉冲星导航的原理与方法、守时与同步定位/守时问题、组合导航问题及星表位置误差估计问题,发展了X射线脉冲星导航半实物仿真技术。全文主要研究成果如下:研究了X射线脉冲星导航的原理、模型和算法。1)在X射线脉冲星导航原理研究基础上,建立了导航相关数学模型,分析了脉冲星信号特征、探测器性能、观测时间和背景噪声等因素对脉冲到达时间测量精度的影响;2)研究了基于EKF和UKF的脉冲星导航滤波算法,对X射线脉冲星的导航精度进行了数值分析,研究了TOA估计精度、星载时钟钟差、航天器机动和星表方位误差等因素对导航精度的影响。研究并提出了基于X射线脉冲星的自主守时及同步定位/守时的理论、模型和算法。1)研究了基于X射线脉冲星的自主守时原理并建立了相关数学模型,提出基于卡尔曼滤波和样条滤波的守时算法;2)采用线性系统可观性秩条件判据从理论上证明了基于单脉冲星守时的系统是可观的,分析了不同因素对单星守时精度的影响;3)提出一种基于X射线脉冲星进行同步定位/守时的方法并建立了相关数学模型,设计了系统初步方案,采用非线性系统可观性秩条件判据从理论上证明了该同步定位/守时系统的可观性。深入研究了X射线脉冲星/SINS组合导航方法。1)根据X射线脉冲星导航特点和惯性导航优势,设计了X射线脉冲星/惯性简单组合、松耦合组合和紧耦合组合导航方案,给出了各组合导航方案下的系统工作流程;2)基于间接组合滤波方案,建立了X射线脉冲星/SINS紧组合数学模型;3)提出一种X射线脉冲星/SINS组合导航中的钟差修正方法,采用PWCS可观性分析方法验证了所建立系统的可观性;4)以两冲量霍曼转移轨道、Lambert三冲量和四冲量机动变轨轨道为例,分析了X射线脉冲星/SINS组合导航在典型机动轨道中应用的可行性。研究并提出了X射线脉冲星位置误差估计理论、模型和算法。1)针对目前导航中常使用的最小二乘、递推最小二乘和卡尔曼滤波算法,推导了脉冲星位置误差对以上几种导航算法状态估计影响的解析表达式;2)在已知卫星位置信息情况下,提出一种X射线脉冲星星表位置误差估计方法;3)针对星表位置误差为常值和星表误差存在漂移两种不同情况,分别建立了基于CP和CV模型的星表误差估计数学模型,采用PWCS可观性分析方法证明了所建立模型的可观性。发展了X射线脉冲星导航半实物仿真技术。1)提出一种X射线脉冲星信号地面模拟方法,设计并研制了国内首套X射线脉冲星导航半实物仿真系统,该系统具有探测器性能测试、TOA估计算法和导航算法验证等功能;2)基于所研制的半实物仿真系统开展了射线源稳定性试验、不同观测时间和流量的波形恢复试验以及TOA估计算法验证试验,试验结果对X射线脉冲星自主导航研究的可行性验证、系统特性测试和工程应用具有一定的参考价值。论文以导航基本理论为基础,研究了X射线脉冲星导航的理论、方法和半实物仿真技术,梳理并展望了X射线脉冲星导航下一步需要解决的技术问题,研究工作为我国X射线脉冲星导航技术的发展奠定了一定的理论基础,能够为X射线脉冲星导航空间飞行试验的开展提供技术支持。更多还原

【Abstract】 Autonomous navigation is essential in enhancing the autonomous spacecraft operation, and also an important technology that restricts the development of Chinese spaceflight. For the purpose of improving the autonomous operation ability of spacecraft, solving the critical problem and further developing the new theory and methods of X-Ray pulsars navigation, this dissertation studies the principle and algorithms, timing and navigation with consideration of synchronous timing problem, integrated navigation problem, pulsar position error estimation problem and the Hardware-in-the-Loop simulation technology of X-Ray pulsars navigation. The main results achieved in this dissertation are summarized as follows.The X-Ray pulsars navigation theory, methods and implementations are studied and proposed. 1) Based on the principle of X-Ray pulsars navigation, the models of navigation are formulated, and the effects of pulsar characteristics, performance of X-Ray navigation detector, and the observation time and background noise on the precision of TOA are analyzed. 2) Firstly, the navigation arithmetic with Extended Kalman Filter and Unscented Kalman Filter are studied, then navigation precision is analyzed, including the effects of TOA, clock error, orbital maneuver and pulsar position error on X-Ray pulsars navigation precision.The timing and navigation with consideration of synchronous timing based on X-Ray pulsars navigation theory, methods and implementations are developed. 1) The principle and models of X-Ray pulsars timing are formulated, then the timing arithmetic with Kalman Filter and Spline Filter are studied. 2) Based on the observability rank condition of linear system, the system of timing based on single pulsar is proved to be observable, and the effects of different factors on the timing precision are analyzed. 3) A new synchronous location and timing method based on X-Ray pulsars is proposed, alse the models and system architectures are constructed. Based on the observability rank condition of nonlinear system, the system of navigation with consideration of synchronous timing based on X-Ray pulsars is proved to be observable.X-Ray pulsars navigation/SINS integrated navigation system is studied and proposed. 1) Based on the advantages of X-Ray pulsars navigation and SINS, an integrated navigation system is proposed, the architectures and work flows of non-coupled system, loosely coupled system and tightly coupled system are designed. 2) Taking the indirect filter project as instruct, the models of X-Ray pulsars navigation/SINS tightly coupled system are designed. 3) A new clock error control algorithm of X-Ray pulsars/SINS integrated navigation is proposed, based on the Piece-Wise Constant System(PWCS) observability theory, the new method is proved to be feasible. 4) Taking the Homan transfer orbit, three and four pulses Lambert transfer orbit as example, the application feasibility of typical maneuver orbits is testified.X-Ray pulsar position error theory, methods and implementations are developed. 1) The analytic effects of X-Ray pulsar position error on the Least Square arithmetic, Iterative Least Square arithmetic and Kalman Filter arithmetic are deduced. 2) Based on the navigation ephemerides of the satellite, a new estimation algorithm of the X-Ray pulsar position error is proposed. 3) Modeling the X-Ray pulsar position error as Constant Position(CP) model and Constant Velocity(CV) model separately, the pulsar position error system is proved to be observable with PWCS observability theory.The Hardware-in-the-Loop simulation technology of navigation based on X-Ray pulsars is developed. 1) A new simulation method of X-ray pulsars signal is proposed. The first domestic Hardware-in-the-Loop simulation system of navigation based on X-Ray pulsars is designed and developed, which is an effective means to identify the performance of X-Ray navigation detector, verify the TOA estimation, and test the arithmetic of pulsars navigation. 2) The experimentations of X-Ray sources stability, signal fusing with different observation time and flux, and TOA estimation arithmetic are carried out, and the results of which are helpful to verify the feasibility of pulsars navigation, test the system performance and apply the navigation based on X-Ray pulsars in the future.Based on the basic navigation methods, this dissertation expands the research domain of the current X-Ray pulsars navigation by developing the X-Ray pulsars navigation theory, methods and Hardware-in-the-Loop simulation technology, teases and views the future crucial works of X-Ray pulsars navigation. The present work provides much theoretical significance and lays a solid foundation to future study of X-Ray pulsars navigation, and can also provide technological supports for the flight experiments of X-Ray pulsars navigation.更多还原