An algorithm for controlling multiple robots designed in Georgia Tech University allows robots to move in right formation in the most efficient way for a given goal. The robots are instructed to spell a word, and starting with a random configuration, they efficiently change their relative positions so that they spell each letter of the word, by traveling the minimum required distance. Each robot starts without a previous knowledge of its location or memory. All they use is the algorithm to locate each other with respect to other robots.  The Algorithm has been designed by a Masters Student, Ted McDonald. He is now working on a system that would allow him to direct a leader robot remotely so that the other robots could follow the leader. The system might have applications in controlling a pack of military vehicles or even aerial robotic vehicles, due to the 3D motion tracking capability.

Reference:

http://www.wired.co.uk/news/archive/2011-05/9/autonomous-robots-formations