Spacecraft Attitude Fault-tolerant Maneuver Control with Flexible Prescribed Performance

This paper studies fault-tolerant control of the spacecraft attitude control system with prescribed performance under the coexistence of actuator faults, disturbances and uncertainties. First, a flexible appointed-time prescribed performance function (FAPPF) is proposed, which can significantly improve prescribed performance control robustness to unknown initial errors and avoid repeated and cumbersome parameter adjustments. Secondly, an equivalent fusion error is designed based on FAPPF, and terminal sliding mode is introduced to design a fault-tolerant controller, so that the attitude and angular rate meet the prescribed performance constraints at the same time. Further, the improved gray wolf optimization algorithm (IGWO) is introduced for online tolerant allocation of actuator control, which satisfies saturation and fault constraints while reducing energy consumption. Finally, numerical simulation proves the controller's superiority and robustness.