The dynamics of collective sorting robot-like ants and ant-like robots

A distributed sorting algorithm, inspired by how ant colonies sort their brood. is presented for use by robot teams. The robots move randomly, do not communicate. have no hierarchical organisation, have no global representation. can only perceive objects just in front of them, but can distinguish between objects of two or more types with a certain degree of error. The probability that they pick up or put down an object is modulated as a function of how many of the same objects they have met in the recent past This generates a positive feed-back that is sufficient to coordinate the robots' activity, resulting in their sorting the objects into common clusters. While less efficient than a hierarchically controlled sorting, this decentralised organisation offers the advantages of simplicity, flexibility and robustness.