Fuzzy logic based fault-tolerant attitude control for nonlinear flexible spacecraft with sampled-data input

This paper deals with the problem of fault-tolerant control (FTC) for nonlinear flexible spacecraft subject to actuator faults and input sampling. Different from the existing approaches, the considered nonlinear flexible spacecraft is approximated by Takagi-Sugeno (T-S) Fuzzy techniques with connecting a set of linear models. To tackle the loss effectiveness of actuator, a general model of actuator failure is developed first. Then, the sampled-data input is converted into a time-delay term by input delay method, and the time delay caused by signal transmission is also taken care of here. By constructing a mixed linear-quadratic and H∞ performance, a robust FTC algorithm with less conservatism is proposed to ensure the required attitude maneuvering of flexible spacecraft in the presence of external disturbance and elastic vibration. Finally, a practical example with simulation results are carried out to show the effectiveness of the proposed FTC strategy.