APPLICATION OF ROBUST DIRECT ADAPTIVE CONTROL TO THE LONGITUDINAL DYNAMICS OF A FIGHTER AIRCRAFT.

Abstract

The authors investigate the use of a robust direct adaptive controller (RDAC) for controlling the linearized time-varying dynamics of the longitudinal motion of an F-16 aircraft and compare its performance with that of gain scheduling and fixed controller schemes. The RDAC used in this study has been recently developed and analyzed by P. A. Ioannou and K. Tsakalis (1986) and shown to be robust with respect to unmodeled dynamics, bounded disturbances, parameter variations and other plant uncertainties. Four different control schemes are simulated and their performance is compared for different input commands over a complete flight envelope. The simulation results show that the control schemes which use the RDAC perform much better than the fixed and gain-scheduling control schemes.