A laser and image based navigation and guidance system for autonomous outdoor-indoor transition flights of MAVs

Micro Aerial Vehicles (MAV) with hovering capabilities are predestined to explore hazardous areas in order to support emergency and rescue forces. Possible areas of application are urban terrain close to buildings or indoor environment. Especially the autonomous access to buildings is highly demanding due to insufficient GNSS reception in urban terrain and narrow passageways into buildings. Nevertheless, in order to allow exploration of buildings, this paper presents a complete flight system that enables a MAV to transit a passageway into a building to explore this building autonomously. For that, neither any prior knowledge about the building's structure, nor any maps are necessary. Thus the navigation filter uses relative motion estimation in order to substitute GNSS information. In order to further increase the independency from position measurements, the flight guidance is designed in way to maneuver the MAV relative to the entrance, using laser rangefinder and image measurements. The successful operation of the presented system is validated in several real flight experiments.