APPLICATION OF FEEDBACK LINEARIZATION METHOD IN A DIGITAL RESTRUCTURABLE FLIGHT CONTROL-SYSTEM

The proposed control system is applied to aircraft failures occurring with the control effectors or airframe. The failures are identified as parameter changes in the six-degree-of-freedom nonlinear equations of motion by the recursive least-squares algorithm. The control parameters are updated using the latest estimated system parameters. In order to allow one to use a digital computer in implemetations, a discrete-time servo controller is designed for the actuators of the control surfaces and engine. The reference inputs are given by the continuous-time control law that is derived without considering actuator or engine dynamics. The frequency-dependent optimal regulator is employed in the design of the servo controller to eliminate input fluctuation. Performance of the control system is demonstrated through computer simulation using the nonlinear model of an aircraft that has half its right wing broken off.