Experiments with autonomous mobile radios for wireless tethering in tunnels

Tunnels are a challenging environment for radio communications. In this paper we consider the use of autonomous mobile radio nodes (AMRs) to provide wireless tethering between a base station and a leader in a tunnel exploration scenario. Using a realistic, experimentally-derived underground radio signal propagation model and a tethering algorithm for AMR motion control based on a consensus variable protocol, we present experimental results involving a tele-operated leader with one or two followers. Using radio signal strength measurements, the followers autonomously space themselves so as to achieve equal radio distance between each entity in the chain from the base to the leader. Results show the feasibility of our ideas.