Effect of Grouping in Local Communication System of Multiple Mobile Robots

When the size of distributed robotic system becomes large, local communication system is considered appropriate for cooperation in the light of cost and capacity. The behavior of robots has a respectable effect on the efficiency of local communication system. When the number of robots required for cooperative tasks is given, it is therefore essential to know what kind of behavior robots should take so that information is passed to those robots efficiently. Group behavior is considered to have advantages in improvement of communication performance, as previous researches show its effectiveness in such tasks as sample collecting or searching. This paper analyzes the effect of group behavior on the performance of local communication system of multiple mobile robots. We derive a set of differential equations that describe the relationship between group size and the information diffusion among robots. The analytical results show the effectiveness of group behavior and allow us to calculate the optimal group size that minimizes the diffusion time for desired number of robots, even if the number is stochastically distributed. The validity of the analysis is verified by computer simulation.