Congregation behaviour in a robot swarm using pheromone communication

Characteristically, social insects are extremely reliant on their use of pheromones to maintain their social activities as a colony unit. This paper describes an on-going project to investigate the possibility of using pheromone communication in a robot swarm. The particular example of pheromone communication considered here was inspired by the queen bee pheromone. This pheromone is only emitted by a queen bee and has a major influence on the colony. One of its main functions is to attract and stabilize the other members of the colony. In robotic systems, one of the proposed applications for this behaviour is to allow swarm members to locate and recognize a robot leader that releases the appropriate pheromone signal. The robot pheromone is also used to direct grouping behaviour in the robots. This paper provides details of the swarm robots used in the project, their sensors and the simple reactive control algorithm that was developed to mimic the insect response to the queen bee pheromone. Results of practical experiments are also described.