This paper treats the question of output trajectory tracking in nonlinear systems in the presence of uncertainty. It is assumed that the nominal system is decouplable using state variable feedback. An adaptive control law is derived such that in the closed-loop system, output vector asymptotically converges to the given reference trajectory. The controller includes a dynamic system in the feedback path. This result is applied to design a flight control system to control roll angle, angle of attack and sideslip in rapid, nonlinear maneuvers of aircraft.
Singh, S. N.,
Wells, W. R.
Adaptive Control of Decouplable Systems and Nonlinear Flight Control Systems.