Flight Demonstrations of Self-directed Collaborative Navigation of Small Unmanned Aircraft

The development of small, autonomous UAVs that can operate in complex environments as part of large coordinated groups will enable many new applications at fractions of the cost of current systems. A fleet of fixed-wing aircraft has been developed to create an intelligent aerial platform that has demonstrated various autonomous capabilities. By means of a downward-looking camera, a single aircraft autonomously follows a roadway using the natural features of the scene in conjunction with onboard sensors, without the use of GPS or prior knowledge of the road’s coordinates. A forward looking camera is used to perceive obstacles in the aircraft’s flight path by segmenting images into sky/no-sky regions and classifying no-sky regions above the horizon as obstacles. The tracking of friendly ground vehicles – for which GPS information is known but path information is not – is performed using circular and sinusoidal orbits to maintain desired proximity regardless of ground vehicle motion. Teams of two or three aircraft demonstrate convoy protection by providing persistent surveillance around a moving ground vehicle. The team either flies in rigid formation, providing a large area of coverage around the ground vehicle, or the aircraft coordinate several separate actions that provide both lateral (side to side) and longitudinal (front to back) surveillance of the ground vehicle’s path. Details of the hardware platform and each capability are described and results of flight demonstrations are presented.