Decentralized fuzzy fault tolerant control for multiple satellites attitude synchronization

Abstract-This paper presents a decentralized adaptive approximation design to achieve attitude tracking control for decentralized formation flying in presence of control input saturation, model uncertainties, external disturbances and re action wheel faults. A nonsingular fast terminal sliding mode control is designed for finite time distributed cooperative attitude synchronization. In the proposed control scheme, a fuzzy logic system (FLS) is introduced to approximate unknown individual satellite attitude dynamics on-line due to the actuators fault. In order to achieve the capability of fault management without the involvement of ground station operators, the proposed control laws do not requite an explicit fault detection and isolation mechanism. In the attitude control system of each satellite four reaction wheels are placed in a pyramid configuration, numerical simulation results including actuator dynamics and initial conditions´ uncertainties show that the proposed strategy with FLS can compensate for the fault and the system continues to operate satisfactorily with wheel voltage or wheel speed faults and the closed loop distributed tracking control system is stochastically stable. Several simulation examples compared with the existing decentralized fault tolerant controller are presented for illustrating the effectiveness of the proposed fault tolerant control methodology.