Robot Swarms – What can they do?

Swarm robotics has been chosen as one of the three case studies of the ASCENS project.  But why are robot swarms interesting, and why are they a useful case study for the ASCENS project?  Our contention is that for many real-world problems, it is often more effective to use large cooperating teams of  simple, cheap robots than to use a single complex robot. In Nature, ants can build complex nests that are orders of magnitude larger than a single ant, and whose construction lasts many ant lifetimes. Similarly, we envision future swarms of robots performing tasks autonomously, in a robust parallel way.

In the following video,  a group of robots team up to transport an object that is too heavy for a single robot to move. Note that the control is distributed - the designer of the system set up simple rules to ensure that the robots would cooperate to move the object. But the rules are set up in such a way that the number of robots doesn't need to be specified in advance.  So the same control could be used with two robots, or a hundred robots. And the control would still work if two robots happen not to boot up at the start of the experiment. The video was taken from experiments conducted in the swarm-bots project (http://www.swarm-bots.org), which concluded in 2005. In the Ascens project we will be using a robot with a similar form factor, but with much more advanced sensors, actuators and computational abilities (see previous post http://blog.ascens-ist.eu/2011/03/ensembles-and-mobile-robots-what-is-the-link/).



This kind of distributed control has the potential to provide flexible, robust systems. The problem is that to date, swarm robotic systems tend to be designed in an ad-hoc fashion, based largely on the intuition of the system designer. It is very hard to predict in advance what such systems will do, or to be able to provide any formal guarantees about their behaviour. By the end of the ASCENS project, we hope to have some interesting solutions to this problem.