NONLINEAR ADAPTIVE-CONTROL FOR HIGH-ANGLE OF ATTACK FLIGHT

This paper presents a nonlinear methodology for the control of a high angle of attack aircraft, in particular, a modified F-18 aircraft. As a modern combat aircraft demands better maneuver ability and performan ce over domains which include high angles of attack, research in high angle of attack is presently at an advanced stage. An adaptive control ler is developed to maneuver an aircraft at a high angle of attack eve n if the aircraft is required to fly over a highly nonlinear flight re gime. The adaptive controller presented in this paper is based on nonl inear prediction models, and can be constructed to minimize the given cost function or the difference of a described Lyapunov function with respect to the control input at each step. A controller uses system id entification parameters to calculate a command signal so that the outp ut of system follows the reference trajectory. The control is calculat ed to let system follow the reference trajectory under some constraint s. This paper shows that nonlinear adaptive control can he utilized ef fectively to control high performance aircraft such as the F-18 aircra ft for rapid maneuvers with large changes in angle of attack.