Controlled steady gliding and approximate trajectory tracking for vehicles subject to aerodynamic forcing

In this paper we present a control law that yields exponential stability of steady gliding motions of the conventional take off and landing (CTOL) aircraft model. We interpret the CTOL aircraft model as an interconnected system and prove closed-loop exponential stability by constructing a Lyapunov function. We use the stability of steady gliding motions to propose a methodology for approximately tracking desired trajectories. The stabilization and tracking methods presented here are also applicable to other air and underwater vehicles subject to aerodynamic moments, and lift and drag forces. One of the attractions of tracking based on stable gliding is the very low control effort requirement compared to dynamic inversion based methods. We demonstrate the proposed method with a simulation of the CTOL aircraft model.