Tracking and maneuver regulation control for nonlinear nonminimum phase systems: application to flight control

We study the problem of tracking control and maneuver regulation control for a nonlinear nonminimum phase control system. First, a tracking controller, consisting of feedforward and static-state feedback, is designed to guarantee uniform asymptotic trajectory tracking. The feedforward is determined by solving a stable noncausal inversion problem. Constant feedback gains are determined based on linear quadratic regulator (LQR) optimization and assumed satisfaction of a robustness inequality. A maneuver regulation controller is obtained from the tracking controller by introducing a suitable state projection that is related to the LQR feedback gains. Properties of the closed loop, including local asymptotic convergence of the transverse errors are described. A multivariable flight control problem is used to demonstrate the approach.