Active fault-tolerant control system against partial actuator failures

A novel approach for integrated fault detection, diagnosis and reconfigurable control systems design against actuator faults is proposed. The scheme is based on a two-stage adaptive Kalman filter for simultaneous state and fault parameter estimation, statistical decisions for fault detection, and activation of controller reconfiguration. Using the information from the fault detection and diagnosis scheme, the reconfigurable feedback controller is designed automatically based on an eigenstructure assignment technique. To eliminate the steady-state tracking error, a reconfigurable feedforward controller is also incorporated using a command generator tracker technique. The following fault types and input signals are considered: abrupt and incipient, single, multiple and consecutive faults, constant and arbitrarily varying reference inputs. The effectiveness and the superiority of the proposed approach are demonstrated using an aircraft example.