基于分数阶滑模的航天器姿态鲁棒控制

Robust Control of Spacecraft Attitude Based on Fractional Order Sliding-mode Controller

针对存在外部扰动及转动惯量不确定性的高精度高稳定度的航天器姿态控制问题,提出了一种具有强鲁棒性的分数阶滑模控制器。首先,在修正罗德里格参数描述的航天器数学模型基础上,导出了便于分数阶滑模控制器设计的等效数学模型。其次,在传统滑模控制的滑模面与控制律中均引入分数阶微分算子,利用分数阶微分算子的快速收敛性与信息记忆性,设计了分数阶滑模控制器,并使用Lyapunov理论与分数阶稳定性理论证明了整个系统的稳定性。最后,仿真试验表明,分数阶滑模控制器具有高精度、强鲁棒性和良好的抗干扰性。

To deal with the high precision and high stability attitude control problem of a spacecraft model with external disturbances and inertia uncertainties,a new strong robust fractional sliding model controller was proposed.Firstly,based on the mathematical model of the spacecraft described with the modified Rodrigues parameters,an equivalent mathematical model was deduced,which was convenient for the design of the fractional sliding mode controller.Secondly,the fractional differential operator with rapid convergence performance and good information memory ability was introduced into the sliding surface and control law,and a fractional sliding mode controller was proposed.The entire system stability was proved with the Lyapunov theory and the fractional-order stability theory.Finally,numerical simulations demonstrate the high stability,strong robustness and excellent interference resistance ability of the fractional sliding mode controller.