This paper aims to solve the control problem of coupled spacecraft tracking maneuver in the case of actuator faults, inertia parametric uncertainties, and external disturbances. Firstly, the spacecraft attitude and position coupling kinematics and dynamics model are established on the Lie group SE(3), and the coupled relative motion tracking error model is derived by exponential coordinates. Then, considering the actuator faults, an adaptive fuzzy scheme is proposed to estimate the lumped disturbances in real time, and a novel modified fixed-time terminal sliding mode fault-tolerant control law is developed to deal with the actuator faults and compensate the lumped disturbances. Next, the Lyapunov method is used to prove the stability and convergence of the system. Finally, the proposed controller can achieve fast and high-precision fault-tolerant control goals, and its effectiveness and feasibility are verified by numerical simulation.

This paper aims to address an integrated relative attitude and position fault-tolerant control strategy between a follower spacecraft and a leader spacecraft for coupled spacecraft tracking maneuver in the case of inertia parametric uncertainties, external disturbances, actuator failures, and saturation. The coupled rotational and translational kinematics and dynamics of the rigid spacecraft are derived on the Lie group SE(3), where the actuator failures and saturation are taken into account. Then, a 6-DOF extended state observer is proposed by using terminal sliding mode technique to estimate the lumped disturbance in finite time. An adaptive generalized super twisting algorithm of fault-tolerant controller is developed to guarantee the finite-time stability based on the estimated lumped disturbance information. The stability of the closed-loop system is proved in spite of the aforementioned disturbances via the Lyapunov analysis. Finally, the numerical simulation illustrates the effectiveness of the proposed control strategy.

A generalized super-twisting second-order sliding mode adaptive fixed-time control law, which is used for spacecraft pose tracking in the presence of internal and external uncertainties, is proposed. Lie group SE(3) (for special Euclidean group), which is the configuration space for rigid body motion, is used for modeling the six-degrees-of-freedom dynamics of spacecraft. A fixed-time sliding mode surface is proposed and applied to design an generalized super-twisting sliding mode control law. A novel dual-layer adaption law for the controller is proposed to the ensure the gains varying rapidly with the disturbance. The adaptive second-order sliding mode controller guarantees a uniform exact convergence for the closed-loop tracking control system with less energy consumption. Numerical simulations are performed to demonstrate the excellent performances of the control law.