带变速控制力矩陀螺的航天器自适应姿态控制

航天器高精度姿态控制容易受到参数误差的影响，自适应控制能够合理地估计参数，使基于模型的控制器设计易于实现。自适应参数分为主星体惯量、变速控制力矩陀螺框架转子惯量及动摩擦系数3组，按参数分组对带变速控制力矩陀螺的航天器详细动力学模型进行变换，采用Lyapunov方法设计出姿态控制器、变速控制力矩陀螺群操纵律及参数自适应更新律，操纵律中引入加权矩阵以缓解陀螺奇异问题。理论分析和数值仿真表明闭环姿态控制系统全局一致最终有界稳定，参数自适应更新能有效减小角速度跟踪误差，使姿态四元数误差收敛更快。参数估计虽然不能准确收敛到其真值上，但均在可接受的范围内。

Adaptive Attitude Control of Spacecraft with Variable Speed Control Moment Gyroscopes

Spacecraft precise attitude control is easily affected by system parameter errors. Adaptive control can estimate parameters reasonably and make the model based controller design more easily. Adaptive parameters are sorted into three groups includingspacecraft main body inertia, VSCMGs gimbal androtor inertia, and their dynamic friction coefficients. The detailed spacecraft attitude dynamics model considering VSCMGs gimbal and rotor friction was transformed according to the parameter groups. The attitude controller, VSCMGs steering law and parameters adaptive updating law were developed by Lyapunov method. Weight matrix was imported into the steering law to relief the gyroscopes singularity problem. Theory analysis and numerical simulation prove that the closed loop control system is global uniformly and ultimately bounded stable. Parameters adaptive updating can effectively reduce angular velocity tracking errors and make attitude quaternion errors converging faster. Parameter estimates can not accurately converge to their real values, but they are all within acceptable scopes.