【作者】 齐映红；

【导师】 曹喜滨；

【作者基本信息】 哈尔滨工业大学 ， 飞行器设计， 2009， 博士

【摘要】 小卫星具有成本低、重量轻、研制周期短和发射灵活等优点,利用小卫星平台作为空间攻防武器具有明显的优势。本文以攻防小卫星的追踪拦截制导为研究背景,针对小卫星的特点,对天基拦截的远程导引段、中制导段和末制导段的轨道优化设计和精确制导等关键技术进行了深入研究。首先对小卫星平台用于空间攻防时所具备的功能进行了分析,归纳了小卫星攻防任务的轨道机动模式;然后基于系统工程思想对小卫星攻防任务进行规划,明确了攻防任务的飞行阶段划分、组成元素及关键技术,通过分析给出了可行的拦截方案;最后建立了系统级的拦截任务模型。本章内容为后续的研究奠定了基础。针对小卫星平台的推力和燃料受限等因素,主要研究天基拦截远程制导律的设计方法。建立了两圆轨道之间Lambert拦截问题的初始条件、转移时间和燃料消耗量之间的关系,提出了燃料、时间以及交会角等约束条件下的多脉冲拦截问题求解方法,并设计了减少燃料消耗和缩短拦截时间的远程制导策略及交会角受限情况下的最优多脉冲拦截问题的求解算法,显著降低了约束情况下的天基拦截燃料消耗和拦截时间。针对攻防小卫星共轨式追踪拦截方式的远程制导问题,建立了考虑J2摄动影响下的有限推力轨道转移问题的准最优解析方法。在自由滑行段采用开普勒轨道改进解析方法,提出了求解追踪拦截问题的迭代制导算法;基于逐次消除终端零控脱靶量的思想,并采用遗传算法对点火时刻、关机时刻和推力方向进行优化,设计了一种多次推力弧段的制导算法,显著降低了有限推力制导问题的计算量。对几种典型零控拦截流形的精度进行了数值仿真,分析了中制导结束时刻的必要条件;推导了以零控拦截流形为终端约束的最优中制导律的表达式;在此基础上,考虑小卫星平台特殊的发动机布局,设计了通过调整相对距离、相对距离的一阶导数和视线角速度将拦截器导引到零控拦截流形上的中制导律,能够满足中、末制导的交班条件。设计了末制导段的模糊模型参考学习控制(FMRLC)算法。在该算法中采用了基于动态聚焦(DFL)机制的模糊控制方法和模糊规则的自适应学习,改进了自学习过程中学习区域过小的问题,增强了末制导系统对干扰的适应能力,有效地提高了末制导律的鲁棒性和制导控制精度。更多还原

【Abstract】 Small satellites have several advantages including lower mission cost, smaller size, built and launched more guickly, and so on, which make small satellites predominant to be the platform of space weapons. In this paper, the tail-case intercept mission scenario utilized a smallsatellite as an interceptor is the research background. The key technologies including the optimal trajectory planning and precision guidance technology are systematically studied. The long-range guidance scheme, midcourse and terminal guidance law are designed and analyzed based on the characteristic of small satellites.Firstly, the operation functions of small satellites worked as the platforms of space weapons are introduced. Then, the operation mission based on small satellites is planned with system view, and the components and key technologies are defined, and also the flight phases of the whole rendezvous trajectory are demonstrated. At last, the mission model is established. This research work is the basis of the following research.The long-range guidance law considers the situation that the fuel the smallsatellite holds and the transfer time are limited. The relation of characteristic velocity, transfer time, and initial angle for Lambert’s transfer problem between two circular orbits is analyzed by both analytical and numerical methods. The solution methods of the optimal intercept problem under the constraints of fuel, transfer time, and rendezvous angle are investigated, at the same time, the method decreasing the fuel expenditure and transfer time is given. The simulation results prove the long-range guidance law is effective.For the problem of small satellite co-orbital maneuver, the analytical guidance method with J2 perturbation based on the homogenious central force field is derived. The iterative guidance arithmetic to solve the tail-case intercept problem is present, in which the analytical solutions are substituted by the orbit papameters of Keplerian orbit. An approach to solve multiple-thrust transfer problem is investigated by use of the design idea of every thrust eliminating a part of the position miss at the terminal time. Genetic algorithm is utilized to optimize the ignition time, thrust time and thrust direction. Simulation results test that the fuel expenditure is decreased.The quantitative precision analysis for several classic zero-effort-intercept manifolds is made, and the necessary conditions at the burnoff time of the midcourse phase are deduced from the simulation results. The optimal midcourse guidance with the terminal constraints being the zero-effort-intercept manifold is derived. A midcourse guidance scheme by regulating the relative distance, the first order derivative of the relative distance, and the sightline angle speed is given, which can satisfy the initial requirety of the terminal guidance phase.Fuzzy Model Reference Learning Control (FMRLC) is designed. In the algorithm, dynamically focused learning (DFL) strategy based fuzzy control and adaptive learning of fuzzy rules are adopted. The problem of too small learning region in the learning is overcomed. The ability to adapt the disturbance and the control precision are improved.更多还原