An army of self-assembling swarm bots can get together and do certain jobs. But because each of them has a unique and limited perspective of the world, they could always use a little help. Enter the overhead quadrotor drone. This guy has the advantage of a bird's eye view of the area and can coordinate the team to work together more efficiently to overcome obstacles or perform tasks.
In the video below, the quadrotor uses stereo imagery to compute how steep a hill is, runs an onboard simulation to see how many ground robots will have to team up to make it over and then directs the robots to team up and go over the bridge. The idea was demonstrated in Portugal at the 2012 Intelligent Robots and Systems conference by a team of researchers from the Universite Libre de Bruxelles and Instituto Universitario de Lisboa. via IEEE Spectrum