Dynamic notch filtering control for fault-tolerant actuators of fly-by-wire helicopters

The paper deals with the control design of a fault-tolerant actuator for fly-by-wire helicopters, capable of compensating both failure effects and jump resonance phenomena. The study, focused on the performance analysis in case of servovalve coil faults, points out that a standard reconfiguration based on demand amplification can imply jump resonances. The proposed strategy eliminates the problem by correlating the jump frequency to the system characteristics, and by inserting a dynamic notch filter in the actuator closed-loop control.