Synchronized Fault-tolerant Attitude Control for Spacecraft Formation with Communication Delays

In this paper, a synchronized fault-tolerant attitude control law for multiple spacecraft system under a direct topology is investigated, in which communication delays between formation members and external disturbances are considered simultaneously. Initially, a finite-time observer is proposed for individual spacecraft to estimate the total uncertainties caused by loss-of-effectiveness actuator faults, additive actuator faults and external disturbances. On basis of the observed information, a synchronized attitude control algorithm is constructed with integral sliding mode method, and system stability is analyzed by using Lyapunov-Krasovskii theory. Finally, simulated results show the validness of the designed control scheme.