存在物理约束的时变转动惯量航天器姿态控制

Adaptive attitude control with physical constraint andtime-varying rotational inertia

对存在角速度和控制输入有界的快速机动航天器姿态控制问题,设计了一种自适应双环姿态跟踪控制器。将虚拟有界角速度作为运动学方程的虚拟控制输入,使姿态控制问题降阶为角速度跟踪问题;构建递归自适应算法估计时变转动惯量及其微分,并基于障碍李亚普诺夫函数和线性回归算子,设计了角速度跟踪误差有界的变增益自适应姿态控制器。结果表明:该控制策略能使抓捕非合作目标航天器的姿态呈指数收敛到期望轨迹,且收敛轨迹不受外部干扰和抓捕瞬间的强干扰影响;在整个控制过程中,航天器的角速度小于0.4 rad/s,控制力矩小于10 N·m,满足了航天器对角速度和控制输入有界的物理限制。

A robust adaptive attitude controller based on dual-loop design method was proposed for controlling rigid-body attitude in the presence of time-varying rotational inertia,bounded angular velocity and control torque.To satisfy the constraint of angular velocity,the bounded virtual angular velocity was designed to ensure the kinematical equation converge rapidly,and based on barrier Lyapunov function,a variable gain adaptive attitude controller was designed to guarantee the bounded errors between real and virtual angular velocities,in which,recursive adaptive algorithm was constructed to estimate the timevarying rotational inertia and its differentiation.The results showed that the control strategy can make the attitude of the non-cooperative target spacecraft converge exponentially to the desired trajectory,and the convergence trajectory was not affected by external interference and strong interference at the moment of capture.In the entire control process,the angular velocity of the spacecraft was less than 0.4 rad/s and the control torque was less than 10 N·m,thus meeting the physical limitations of the spacecraft.