Real-time on-board object tracking for cooperative flight control

One of possible situations for cooperative flights could be a scenario when the decision on a new path is taken by a certain fleet member, who is called the leader. The update on the new path is transmitted to the fleet members via communication that can be noisy. An optical sensor can be used as a back-up for re-estimating the path parameters based on visual information. For a certain topology, the problem can be solved by continuous tracking of the leader of the fleet in the video sequence and re-adjusting parameters of the flight, accordingly. To solve such a problem a real time system has been developed for recognizing and tracking 3D objects. Any change in the 3D position of the leading object is determined by the on-board system and adjustments of the speed, pitch, yaw and roll angles are made to sustain the topology. Given a 2D image acquired by an on-board camera, the system has to perform the background subtraction, recognize the object, track it and evaluate the relative rotation, scale and translation of the object. In this paper, a comparative study of different algorithms is carried out based on time and accuracy constraints. The solution for 3D pose estimation is provided based on the system of Zernike invariant moments. The candidate techniques solving the complete set of procedures have been implemented on Texas Instrument TMS320DM642 EVM board. It is shown that 14 frames per second can be processed; that supports the real time implementation of the tracking system with the reasonable accuracy.