Orbit control of spacecraft flying in formation requires attitude information, and in some cases re-quires the satellite to be in a specific attitude. The attitude control system needs to track and capture a target attitude. Therefore, for these missions, the operatiom of orbit and attitude control need to be synchronized. In this paper the design and implementation of autonomous orbit and attitude synchronous control for multi-pie spacecraft formation are presented. These include the control laws for formation maintenance and the im-plementation of an orbit control system using GPS code pseudorange measurement output feedback, For modeling formation flying, the head of fleet is selected as the target reference and all member spacecraft in the formation pattern are described with respect to it. The relative attitude kinematics and rehtive dynamicsequations are developed using the relative modified Rodrigues parameters for relative attitude representation. Nonlinear control laws for large attitude angle acquisition and tracking are also presented, along with the im-plementation of this nonlinear attitude control system using GPS phase pseudorange measurement output feedback. Computer simuhtions are provided for the EO-1/Landsat 7 formation scenario, verifying that the development of the synchronous orbit and attitude control laws for formation flying is correct, and that the implementation of this control using only GPS for output feedback is feasible.%鉴于编队飞行之中卫星不但对轨道有要求,而且对姿态也有要求,例如有的编队飞行卫星在惯性空间中有指向控制的要求,或者相互之间有保持一定的姿态关系的要求,同时在轨道控制过程中也需要姿态信息,因此在编队飞行的建立过程中,需要考虑姿态和轨道的协调控制和同步控制问题.本文提出了用汗同步控制的相对轨道和相对姿态运动学和动力学模型、控制率的选择和设计以及用GPS的伪距和载波相位实现轨道和姿态同步实时反馈控制方法.其中包括用修改的Kodrigues参数实现无奇异的大姿态机动的非线性状态跟踪控制.对EO-1/Landsat 7编队飞行的同步控制进行了数字仿真,证实了设计的正确性和实现的可行性.
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