Analysis Of Configuration And Design And Research Of Control For Satellite Groups Based On Two-Station-System

Small satellites based Two-Station-System refers to a cluster of small satellites which will be governed by both ground station and space station in this paper. Space station will be a main node of space-based information network to small satellite groups. Considering support of space station to small satellite groups, this will be form a new information network of space and ground, which will be important to such applications as earth observation, remote sensing and military affairs etc.Two kinds of configuration and design of small satellites groups based on Two-Station-System are discussed emphatically in the dissertation. The position keeping and attitude control about small satellites is also studied. The main contents are as follows:After the summary of the requirements and applications of space station and small satellites groups, a direct equation of relative motion based on kinematics method is elected. Firstly, the equation of relative motion based on kinematics is presented in detail, so relative motion parameters may relate directly with orbit elements. Secondly, relative motion is simplified from practice, so it is convenient for orbit analyzing and design. Then, considering safety and limit of relative distance of formation flying, the select area of relative orbit elements are studied. Finally, perturbation of relative motion on air drag and J2 term are induced in detail.In chapter 3, the characteristics of relative motion of small satellite based on ground station are firstly analyzed, in which using spherical trigometry, the analytic formulas evaluating the longitude ranges of ascending node which can cover the target are deduced with J2 precession. With the solution, the longitude ranges of ascending node limited by the cross-time can be gained. Secondly, a serious of characteristics of small satellite to space station is studied. According to the results of small satellite to ground station, the longitude ranges of ascending node limited by the cross-time can be gained relative space station.Using the analytic results above, in chapter 4, a special data relay constellation is designed for space station, which include mainly the selection of orbit altitude, eccentricity, inclination, longitude of ascending node, the number of orbit and distribution of satellite. Orbit drift and inter-satellite link is also considered.In the following content, configuration and strategy, position keeping and attitude control of formation flying are researched. With kinematics and dynamicsmethod separately, configuration and design of formation flying are studied. An example about earth observation is given, in which space station is reference satellite, and configuration of formation flying is circle in track of sub-satellite point. The impact of J2 precession to formation flying is studied too. Then relative position keeping of formation flying is presented. Finally, two kinds of method of relative attitude control are investigated. The first case is that reference satellite (space station) is the center in formation flying. All satellites, which form a large virtual satellite, are both reference and adjoint satellites in the second case.In the last chapter, rotation and translational motion is studied to formation reconfiguration. The emphasis is translational motion. Due to system of control is time-variant system, robust control theory ( H, ) is used to translational control.