Adaptive linear quadratic design with application to F-16 fighter aircraft

Abstract

This paper investigates an adaptive linear quadratic (ALQ) control design with its application to the longitudinal model of the F-16 fighter aircraft. The certainty equivalence principle is used to combine the adaptive law with the control structure of the standard linear quadratic (LQ) problems. The aerodynamics of the F-16 fighter aircraft is linearized at different trimmed conditions, and the traditional gain scheduling LQ design is also implemented. Simulation results demonstrate the effectiveness of ALQ control design over LQ design with gain scheduling, in that it can discern aerodynamics changes and adapt the control laws accordingly. This also helps the system to achieve fault-tolerance to control surface damage. The large computer storage requirement required for a gain scheduled LQ design is also avoided. Copyright © 2004 by the American Institute of Aeronautics and Astronautics, Inc. All rights reserved.