Rational aggressive behaviour reduces interference in a mobile robot team

Spatial interference can reduce the effectiveness of teams of mobile robots. We examine a team of robots with no centralized control performing a transportation task, in which robots frequently interfere with each other. The robots must work in the same space, so territorial methods are not appropriate. Previously we have shown that a stereotyped competition, inspired by aggressive displays in various animal species, can reduce interference and improve overall system performance. However, none of the methods previously devised for selecting a robot's 'aggression level' performed better than selecting aggression at random. This paper describes a new, principled approach to selecting an aggression level, based on robot's investment in a task. Simulation experiments with teams of six robots in an office-type environment show that, under certain conditions, this method can significantly improve system performance compared to a random competition and a noncompetitive control experiment. Finally, we discuss the benefits and limitations of such a scheme with respect to the specific environment