Modeling underwater acoustic communications for multi-robot missions in a robotics simulator

Missions involving multiple Autonomous Underwater Vehicles (AUVs) are gaining increasing popularity with the advent of better control mechanisms and availability of acoustic modems that allow for cooperative networked tasks to be carried out by Unmanned Underwater Vehicles (UUVs). However, high costs associated with offshore testing and the lack of useful tools to accurately simulate multi-AUV tasks has been a hindrance to exploiting the full potential of the field. Even though there exist a few simulators for modeling a single AUV, there is virtually no simulation tool available that allows modeling of acoustically networked communications between multiple AUVs by accurately characterizing the underwater acoustic channel. In this paper we present an overview on modeling of the underwater acoustic channel, taking into account the high degree of local variability of ocean conditions, multi-path echoes and ambient noise, within the framework of an underwater acoustic communications server for the Unified System for Automation and Robotics Simulator (USARSim) robotics simulator.