【作者】 赵玉成；

【导师】 林晓辉；

【作者基本信息】 哈尔滨工业大学 ， 飞行器设计， 2007， 硕士

【摘要】 与传统的单颗大卫星相比,卫星编队的功能更强大、结构更灵活,是未来航天发展的必然趋势。而卫星编队任务的实现依赖于编队卫星之间的相对状态的确定和控制精度,星间相对状态包括相对位置、速度和相对姿态和姿态角速度。本文以“微小卫星编队飞行演示验证方案论证”为研究背景,研究了基于无线电相对测量的星间相对状态确定和控制算法。具体工作如下:首先,着重研究了编队卫星相对轨道和姿态自主确定方法。针对Hill方程的不足,推导了一组包含J2项摄动的相对轨道运动方程。对相对轨道确定,星间测量采用无线电测量距离和方位角方式,并设计了Unscented卡尔曼滤波器,对相对位置、速度进行估计;对相对姿态确定,由卫星自身携带的姿态敏感器实现单星高精度姿态确定,利用星间通信链路进行信息交互,通过简单的数学计算获得星间相对姿态。最后通过仿真表明,这两种方法皆能提供较为精确的相对状态;其次,针对编队飞行卫星队形初始化控制设计了相对轨道模型预测控制器。模型预测控制算法是一种在线滚动优化的闭环控制算法,能够较好地控制存在状态约束、控制约束等各种约束控制问题,并且模型预测优化问题可以转换为在线求解线性规划问题,最后通过仿真验证其有效性;最后,考虑到多数编队任务对星间相对姿态控制精度有着较高的要求,本文以双星编队为例,在前面两章的研究基础上,设计了基于目标视线的卫星编队相对姿态完全分布式变结构协同控制律,并利用李雅普诺夫原理证明了控制律的稳定性。仿真结果表明,这该控制律能够在存在各种干扰力矩及卫星模型的不确定性的情况下,有效地提高编队卫星相对姿态控制精度。更多还原

【Abstract】 Satellite formation offers more powerful and robust architectures than single, traditional large satellite and is an enabling technology for a number space missions. A lot of space missions are depend on the relative state, including the relative position, velocity and relative attitude and attitude angular velocity, determination and control precise. This dissertation takes system demonstration and validation of small satellites formation flying as the background; the theory and algorithms of relative state determination and control are investigated. The main contributions are as follows:First, the relative state autonomous determination approaches are studied detailedly. The traditional Hill equation has many disadvantages, so here we derived a set of relative orbital equation of motion, which takes the J2 pertubation in consideration. To the relative orbit determination, using the intersatellite relative distance and azimuth angle, and an UKF approach is introduced to estimate the relative position and velocity; To the relative attitude determination, each satellite uses its own on-board attitude sensors to determine its attitude, and exchange the information through the communication link between formation satellites, and then the relative attitude is determined through simple mathematical operation. Simulation results indicate that both approaches are effective and suitable for precise autonomous relative state determination.Secondly, a model predictive control methord are designed for the satellite formation initialization control. The main reasons for the interest of control engineers in MPC are therefore its ability to handle inequality constraints systematically and effectively during the design and implementation of the controller and the on-line optimization can be typically reduced to either a linear programming. At last, this approach is demonstrated through the simulation.Finally, considering the majority of formation missions have strict requirements for the relative attitude control accuracy between coordinated satellites in formation. In this thesis, take an example of the mission of two satellites, assuming that the relative position and attitude are known, a variable structure based fully decentralized relative attitude coordination control laws is derived. The stability is proven through Lyapunov function. The simulation results indicate that the proposed control laws can efficiently minimize the relative attitude error in the presence of disturbances and the model uncertainties.更多还原