We have researched the efficiency of cooperative behavior of interacting multirobots. In this paper, we generalize the definition of swarm intelligence and examine the emergence of the generalized swarm intelligence (here we call it “swarm function”) through the task of gathering pucks in a field by interacting simple robots. This robot has a drive system and the simplest means of interaction. The effectiveness of group behavior was studied for various (homogeneous, localized) puck distributions. To evaluate the efficiency of group behavior, we proposed a scaling relation between the task completion time and the number of robots, and examined the relation between the interaction duration and the efficiency of the group. We also proposed a simplified state transition diagram of the group and analysed their characteristics using it.