Signal Strength Coordination for Cooperative Mapping

This work addresses the problem of coordinating a team of mobile robots such that they form a connected ad-hoc wireless network while addressing task objectives. Many tasks, such as exploration or foraging, can be performed more efficiently when robots are able to communicate with each other. All or parts of these tasks can be performed in parallel, thus multiple robots can complete the task more quickly than a single robot. Communication and coordination among the robots can prevent robots from duplicating the effort of other robots, allowing the team to address the task more efficiently. In non-trivial environments, maintaining communication can be difficult due to the unpredictable nature of wireless signal propagation. We propose a multi-robot coordination method based on perceived wireless signal strength between cooperating robots for exploration in maze-like environments. This new method is tested and compared to an existing method that relies on preserving a clear line of sight between robots to maintain communication. The original document contains color images. Supported in part by NSF and NASA. Contract no: DABT63-99-1-0022.