Nonlinear control of PVTOL vehicles subjected to drag and lift

The present study extends and encompasses a previous work on the control of thrust-propelled vehicles which focused on vehicles subjected to environmental reaction forces that are reduced to their drag component, as in the case of spherical bodies. Lift forces associated with other body shapes, like winged aerial vehicles, modifies and complicates the control problem significantly. This paper shows the existence of a generic set of drag-and-lift models for which it is possible to recast the initial control problem into the one of controlling a spherical body, thus allowing for the application of control design methods and analyses developed previously. Beside the obtention of more general nonlinear control solutions that apply to a larger class of vehicles and for which (semi) global stability results can be proved, we view this extension as a step to the automatic monitoring of flight transitions between hovering and high-velocity cruising for convertible aerial vehicles.