The Use of Internal State in Multi-Robot Coordination

Coordination is an essential characteristic of any task-achieving multi-robot system (MRS), whether it is accomplished through an explicit or implicit coordination mechanism. There is currently little formal work addressing how various MRS coordination mechanisms are related, how appropriate they are for a given task, what capabilities they require of the robots, and what level of performance they can be expected to provide. Given a MRS composed of homogeneous robots, we present a method for automated controller construction such that the resulting controller makes use of internal state and no explicit inter-robot communication, yet is still capable of correctly executing a given task. Understanding the capabilities and limitations of a MRS composed of robots not capable of inter-robot communication contributes to the understanding of when and why inter-robot communication becomes necessary and when internal state alone is sufficient to achieve the desired coordination. We validate our method in a multi-robot construction domain.