  This paper presents a model-based, adaptive, nonlinear controller for the
bicopter stabilization and trajectory-tracking problem. The nonlinear
controller is designed using the backstepping technique. Due to the
non-invertibility of the input map, the bicopter system is first dynamically
extended. However, the resulting dynamically extended system is in the pure
feedback form with the uncertainty appearing in the input map. The adaptive
backstepping technique is then extended and applied to design the controller.
The proposed controller is validated in simulation for a smooth and nonsmooth
trajectory-tracking problem.
