针对存在外界干扰的情况下使用单框架控制力矩陀螺(SGCMG)作为执行机构的卫星姿态大角度快速机动控制问题,设计了以Legendre伪光谱算法和滑模控制方法相结合的控制策略。采用能量与时间相结合的最优性能指标,应用Legendre伪光谱算法将最优控制问题转化成非线性规划问题,求解出能量和时间综合最优姿态机动轨迹。以该规划轨迹中的卫星姿态四元数和角速度信息为跟踪期望值,采用滑模变结构控制方法对其进行精确跟踪。该控制方法不仅实现了卫星姿态的快速控制,而且可以有效避免SGCMG陷入奇异状态。

This paper studies and addresses the issue of time efficient large angle maneuver for a rigid spacecraft using single gimbal control momentum gyroscope (SGCMG) in the presence of external disturbances. A real time closed loop control based on the Legendre-pseudospectral method and sliding mode method is utilized to fulfill the mission. An integral function consisting of the square of the SGCMG gimbal velocity magnitude and time is chosen as the cost function. With the help of Legendre-pseudospectral method, the optimal control problem is converted to a nonlinear programming problem, and the optimal solution is derived which contains the desired path to guide the satellite attitude maneuver. The sliding mode method is adopted in the design of the attitude controller to track accurately the desired path comprised of the satellite attitude quaternion and velocity. Simulation results prove the robustness and time efficiency of the derived controller as well as its ability to avert SGCMG singularity.