Stereo vision relative navigation of airborne vehicles

An automated aerial formation (AAF) system comprising:

• an imaging device mounted on a first aircraft the imaging device comprising a first stereo camera and a second stereo camera configured to capture first and second stereo images, respectively, of a second aircraft;
• a network interface communicatively coupled to a flight control system of one of the first aircraft and the second aircraft, wherein one of the first or second aircraft is an unmanned aircraft;
• and
• a controller communicatively coupled to the imaging device and the network interface, and which:
• receives the first and second stereo images;
• generates a three-dimensional (3D) point cloud based on the first and second stereo images;
• identifies a target 3D model in the 3D point cloud;
• identifies one or more discriminating features of the target 3D model, wherein the discriminating features includes at least one of a number of aircraft engines of the second aircraft;
• compares the one or more discriminating features of the target 3D model to more than one candidate pre-defined 3D model;
• and
• identifies the pre-defined 3D model of more than one candidate pre-defined 3D model based a correspondence of the one or more discriminating features in both the target 3D model and the pre-defined 3D model;
• rotates and scales one of a pre-defined 3D model and the target 3D model to find a 3D point registration between the target 3D model and the pre-defined 3D model;
• determines a distance to the second aircraft based on an amount of scaling required to find the 3D point registration;
• determines a relative direction from the imaging first aircraft to the imaged second aircraft based on a boresight angle;
• and
• steers at least the unmanned aircraft into formation relative to the other aircraft based on the distance, the relative pose, and the relative direction.