一种空间目标高精度指向控制方法

针对空间动目标指向任务对卫星提出的高精度控制需求,研究了卫星星体/快反镜二级复合系统的指向控制问题,给出了一种空间运动目标高精度指向控制方法。首先,基于近圆轨道Clohessy-Wiltshire方程获得追踪卫星与目标卫星的位置信息;然后,基于扩展Kalman滤波算法进行多信息融合确定追踪卫星姿态参数,并实时解算出追踪卫星载荷光轴与目标卫星的相对姿态,获得跟踪指向所需的方位角和俯仰角;最后,通过星体一级姿态控制和基于快反镜的载荷光轴二级指向控制,实现对目标卫星的快速、高精度指向。仿真结果表明,该方法可以在保证快速性的同时实现动态指向控制误差小于0.72″。该方法可以实现对空间目标的高精度指向控制,为未来空间中激光通信等航天任务提供技术支持。

A high accuracy pointing control method for space target

In order to meet the requirement of high accuracy control for satellites in space moving target pointing missions, the control method of the two layer attitude system by the spacecraft base and fine steer mirror (FSM) are considered. The high accuracy pointing control method for space moving targets is presented. First, the position information of tracking satellite and target satellite was obtained based on the Clohessy Wiltshire equation of the near circular orbit. Then, the multiple information fusion extended Kalman filter was adopted to estimate tracking satellite attitude. The relative attitude between tracking satellite optical axis and target satellite was calculated in real time so as to obtain the azimuth and elevation angle required for tracking and pointing control. Finally, fast and high accuracy pointing to the target satellite was realized through spacecraft base first layer attitude control and payload optical axis second layer pointing control based on FSM. Simulation results show that the proposed method can keep dynamic pointing error less than 072″. The method presented can realize high accuracy tracking and pointing control of space target and can provide technical support for space missions such as laser communication.