过驱动卫星姿态动态控制分配研究

The Attitude Dynamic Control for Overactuated Satellite

针对受干扰、飞轮故障、安装偏差和饱和影响的过驱动卫星的姿态控制问题提出了一种控制器设计方法。首先建立了过驱动卫星的姿态方程,给出了飞轮安装偏差、故障和饱和的数学描述。随后设计了存在外界不确定干扰和飞轮安装偏差时的滑模控制律,再应用动态控制分配解决过驱动卫星飞轮故障问题,最后考虑飞轮存在饱和时,使用零空间法使飞轮力矩指令保持在可行区间之内。设计的控制方法避免了复杂的控制器设计过程,控制器更为简单,适应性更广,更容易理解且更易于工程应用。

A controller design method is proposed for the attitude control of overactuated satellites under interference, reaction wheel fault, actuator misalignment and saturation. Firstly, the attitude equation of overactuated satellite is established and the mathematical descriptions of reaction wheel installation deviation, fault and saturation are introduced. Then, the sliding mode controller under external uncertain interference and reaction wheel actuator misalignment is designed, and the dynamic control allocation is applied for solving the reaction wheel fault of overactuated satellite. Finally, when the reaction wheel is saturated, the Null-space method is used to keep the reaction wheel torque command within the feasible range. The designed control method avoids the complex controller design process, and the controller is simpler, more adaptable, easier to understand and easier to be applied in engineering.