Control allocation based fault-tolerant control design for spacecraft attitude tracking

This paper presents a fault-tolerant control allocation scheme for overactuated spacecraft attitude tracking systems subject to actuator faults. Taking the effect of fault detection and diagnosis (FDD) uncertainties into account, a performance/robustness trade-off control allocation (PRTCA) strategy is proposed to redistribute the virtual control signals to the remaining actuators without reconfiguring the controller. The proposed PRTCA scheme achieves robustness with respect to the imprecise in fault estimation, and is less conservative than the robust control allocation. To illustrate the performance of the proposed PRTCA strategy, numerical simulations are carried out for a rigid spacecraft in the presence of reaction wheel faults.