应用变速控制力矩陀螺的卫星姿态机动的非线性控制

研究了以变速控制力矩陀螺(VSCMG)作为执行机构的卫星多目标快速机动的控制问题。首先建立了带有多个变速控制力矩陀螺的航天器姿态动力学模型,采用修正的罗德里格斯参数(MRP)描述姿态运动。在考虑执行机构饱和、机动速率限制、控制带宽限制等情况下,设计了基于Lyapunov理论的非线性姿态反馈控制器。针对外部干扰会使控制力矩陀螺的框架角偏移其标称值的情况,采取磁补偿控制来保持框架角在一定范围变化。以采用VSCMG为执行机构的某卫星为例进行了数值仿真,仿真结果验证了提出的非线性姿态反馈控制器的有效性,采取的磁补偿控制也很好地抑制了变速控制力矩陀螺框架角的偏移。

Nonlinear Control of Attitude Maneuver for Satellite Using Variable Speed Control Moment Gyros

The multi-target rapid maneuver control problem is studied for agile satellites with Variable Speed Control Moment Gyro(VSCMG) as actuator.First,the attitude dynamics model of a spacecraft with VSCMGs is presented.Then the Modified Rodrigues Parameters(MRP) are used to describe the attitude.A nonlinear feedback controller based on the Lyapunov theory is developed under various physical constraints including the actuator saturation,the slew rate limit,and the control bandwidth limit,etc.The gimbal angles of VSCMG system can deviate from their nominal values due to external disturbances.A method using a magnetic control law is presented to keep the gimbal angles within a desired range.A numerical simulation is presented on the sample of the attitude maneuver of a satellite with VSCMG.The simulation result demonstrates that the proposed nonlinear feedback controller is effective and the magnetic control keeps down the deviation of the gimbal angles.