【作者】 王华；

【导师】 唐国金；

【作者基本信息】 国防科学技术大学 ， 航空宇航科学与技术， 2007， 博士

【摘要】 交会对接技术是进行空间组装、空间平台补给、空间站人员轮换、在轨维修和深空探测等高级空间操作的一项必需技术。完整的交会对接过程包括远距离导引、近距离导引、平移靠拢、对接和撤离等阶段。在不同阶段有不同的控制目标和约束条件,所面临的轨迹安全问题也不尽相同。本文针对交会对接中存在的控制和轨迹安全问题,系统研究了各主要阶段的控制策略,采用概率及动力学分析等手段建立了轨迹安全的描述指标和计算方法。全文主要工作包括:研究给出了交会对接轨迹安全策略,提出了交会对接碰撞分析模型和计算方法。(1)分析了交会对接各阶段面临的主要轨迹安全威胁,阐述了被动和主动安全策略、目标器的交会对接控制区域等保证交会安全的措施;(2)基于概率思想发展了线性和非线性运动情况下飞行器与空间碎片的碰撞判断方法,提出采用总碰撞概率和拟最大瞬时碰撞概率来综合描述飞行器与空间碎片的碰撞危险程度,推导了通过飞行器和空间碎片各自的状态矢量、位置误差协方差矩阵以及形状尺寸来计算碰撞概率的公式;(3)提出了两种分析追踪器和目标器之间相对轨迹安全的新方法:基于3σ椭球的轨迹安全分析方法和基于碰撞概率的轨迹安全分析方法。提出了远距离导引段特殊点变轨的一种计算策略,建立了飞行器规避空间碎片的机动方法。(1)研究了远距离导引的特殊点变轨策略,针对特殊点变轨策略每次机动目标单一和轨道面修正为小量的特点,提出了将轨道面内调相与轨道面修正分解计算的策略,推导了采用高精度轨道模型的调相和轨道面修正机动计算公式;(2)研究了远距离导引段飞行器规避空间碎片的机动问题,提出了一种双调相轨道机动策略,并给出了碰撞规避机动的计算公式。研究给出了近距离导引段的控制和轨迹安全计算方法。(1)分析了CW制导的误差,提出了一种采用精确模型对CW制导进行修正的制导方法,并针对轨道面外冲量控制存在奇异的问题,提出了轨道面外的控制策略;(2)研究给出了基于CW方程和基于高精度模型的近距离导引段被动轨迹安全分析方法;(3)建立了近距离导引段的碰撞规避机动计算方法。研究给出了平移靠拢段的控制和轨迹安全计算方法。(1)提出了测量误差较大时平移靠拢段的视线控制策略,给出了横向、纵向和悬停的控制方法;(2)针对长方体禁区、球形禁区和锥形禁区三种禁区形式,研究了V-bar逼近和任意方向逼近的纵向安全速度计算问题;(3)提出了安全约束下的最优轨迹设计方法,将冲量和有限推力作用下的最优轨迹设计问题转化为线性规划问题,并给出了将锥形和方形安全区域约束转化为标准线性约束的公式;(4)探讨了紧急避撞机动的设计策略,分析了V-bar和R-bar接近的紧急避撞机动方案。研究得到了视场约束下撤离控制方法,分析得到了分离的被动轨迹安全特性。(1)研究了视场约束下V-bar撤离的径向和切向冲量方案,利用解析和数值结合的方法得到了冲量大小和视场角的关系;(2)针对V-bar分离、R-bar分离和任意方向分离,分别研究了分离后的相对轨迹及被动安全特性。总之,本文在交会对接的控制和轨迹安全分析方面取得了一些进展,其成果对我国载人航天工程交会对接技术的突破和掌握提供了理论参考和技术支持。更多还原

【Abstract】 Rendezvous and docking is a necessary operational technology, which is required for assembly larger units in orbit, re-supply of orbital platforms, exchange of crew in orbital stations, repair of spacecraft in orbit, and deep space exploration. A rendezvous and docking mission can be divided into a number of major phases: far range guidance, close range guidance, final approach, docking and departure. During different phase, the chaser has different control objective, constraint and trajectory safety problem. This thesis focuses on the control strategy and trajectory safety problem during the rendezvous and docking. The control and approach strategy are studied, and the method for describing and calculating trajectory safety is developed by probability and dynamics analysis. The main work and achievements are summarized as follows:The safety strategy of rendezvous and docking is discussed, and the model and method of collision analysis are presented. (1) The source threatening mission safety is analyzed. The passive trajectory protection and active trajectory protection are discussed, and target control zone for rendezvous and docking are analyzed. (2) Based on probability theory, a method for describing and calculating the collision probability between rendezvous and docking vehicle and debris is presented, and the method involves quantitatively analyzing the collision probability using quasi maximum instantaneous collision probability and total collision probability. The method calculating the indexes is developed, and the input required to perform a calculation includes the respective state vectors, position error covariance matrices and physical sizes of objects involved. (3) Two methods to analyze relative trajectory safety between chaser and target are developed, which are 3-sigma ellipsoid based methodology and collision probability based methodology.The strategy calculating maneuver for special point maneuver in far range guidance phase is presented, and maneuver method avoiding collision with debris is built. (1) A method to calculating maneuver for special point maneuver strategy is developed based on the facts that are single objective of every maneuver and tiny correction for orbit inclination and right ascension of ascending node. The basic idea of the method is disassembling calculating for phasing and orbit plane correction, and the equation for calculating maneuver is derived. (2) A method for determining the optimal collision avoidance maneuver is developed, and the two phasing orbits strategy is developed to avoid collision with debris.The control and trajectory safety in close range guidance phase are investigated. (1)The targeting error induced by CW guidance is analyzed and partitioned into several error factors and the corresponding mathematical error models are established. A method to correct the CW guidance error is developed based on precision model, and the control strategy for normal orbit plane is derived. (2) Two methods analyzing approach trajectory safety are built, which are method based on CW equation and method based on high precision orbit model. (3) A method for determining the optimal collision avoidance maneuver for close range guidance phase is developed.The control and trajectory safety in close final approach phase are studied. (1) The sightline control strategy for bad measure precision is developed, and the control methods for vertical direction, approach direction and station keeping are presented. (2)The safe approach velocities are investigated for cuboid, sphere and cone keep out zone. (3)The design method for optimal trajectory under safety constraint is developed. The cone and cuboid keep out zone can be described using line constraint, and then optimal trajectory design can be translated to line programming problem under line constraint. (4) The design strategy of collision avoidance maneuver is discussed, and the collision avoidance scheme is analyzed for V-bar and R-bar approach.The control and trajectory safety in departure phase are investigated. (1) The control of V-bar and R-bar departure in rendezvous and docking under field of view constraint is studied using both analytic and numerical methods. The relationship between field of view and departure maneuver is developed. (2) The departure trajectory and safety characteristic are discussed for V-bar departure, R-bar departure and arbitrary direction departure.In conclusion, important developments have been achieved for the control strategy and trajectory safety analysis method of rendezvous and docking. The method and conclusions in this thesis would be available for rendezvous and docking experiment.更多还原