Fault diagnosis and robust fault-tolerant control for linear over-actuated systems

This paper proposes a novel fault diagnosis and robust fault-tolerant control strategy for over-actuated systems which subject to actuator faults. Firstly, the considered fault is formulated into an additive term (which is referred to as virtual fault). Then an augmented state observer is used to estimate this virtual additive fault. To achieve fault isolation and estimation for the over-actuated system, which is more difficult than that of an ordinary system, this paper considers the actuator fault as a sparse signal and proposes a constrained sparse optimization approach to recover the actual multiplicative fault in the over-actuated system. Based on the fault diagnosis result, a robust fault-tolerant controller is designed by the virtual actuator approach, which aims to construct a reconfiguration block to force the output of the reconfigured faulty plant approximated the behavior of a nominal system. Finally, the proposed fault diagnosis and fault-tolerant scheme is applied to an ADMIRE model. Simulation results demonstrate the effectiveness of the proposed method.