航天器自适应有限时间反步控制

Adaptive finite-time backstepping control for spacecrafts

针对存在转动惯量不确定以及外部干扰的航天器姿态跟踪问题,提出基于反步法的自适应有限时间控制方法。建立四元数描述的系统模型,设计有限时间命令滤波器用以逼近虚拟控制律导数,从而避免反步法设计中的复杂性爆炸和奇异值问题。采用神经网络估计未知非线性函数,设计自适应有限时间控制器,保证系统跟踪误差有限时间收敛。仿真结果验证所提方法的有效性。

In this paper, an adaptive finite-time backstepping control scheme is proposed for spacecraft attitude tracking in the presence of inertia uncertainties and external disturbances. The system model is constructed based on the quaternion, and a finite-time command filter is designed to approximate the derivative of the virtual control. This avoids the complexity explosion and singularity problems. Then, neural networks are employed to estimate the unknown nonlinear functions, and the adaptive finite-time controller is designed to guarantee the finite-time convergence of the tracking errors. Simulation results validate the effectiveness of the proposed scheme.