The drone can view the overall terrain and run simulations of what configurations of robots could best traverse the slopes. Once it has worked out how to assemble the robots into a single machine the drone has to communicate the plan to the swarm using a protocol based on the colored lights they all have. The ground robots adopt a random color and the drone selects the one it wants to communicate with by displaying the same color. They then repeat the process until only one robot has been selected i.e the drone follows the color changes of the selected robot. http://iridia.ulb.ac.be/~mathews/?paper=MatChrOgr-etal2012:iros.pdf Of course if you don’t like the idea of human drones flying over your head you may not be happy about robots getting in on the act as well..."
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