Aggressive Landing Maneuvers for 3DOF Helicopter UAV

VTOL vehicle landing is considered to be a critically difficult task for both Land, Marine, and Urban operations. This paper describes one possible control approach to enable landing of unmanned systems at all attitudes, including against walls and ceilings, as a way to considerably enhance the operational capability of these vehicles. The features of the research include a novel approach to trajectory tracking, whereby the primary system outputs to be tracked are smoothly scheduled according to the state of the vehicle relative to its landing area. Several simulations and experiments, using a low-cost three-degree-offreedom helicopter, illustrate the proposed approach.