Underwater/surface collision avoidance using underwater acoustic communications - a preliminary analysis

Unmanned Marine Vehicles (UMVs) as well as manned vessels increasingly populate our seas. This brings novel challenges such as collision avoidance between manned and unmanned vehicles. With recent developments in the so-called Autonomous Ships topic and large Autonomous Underwater Vehicles (AUVs), the future brings even more unmanned vessels to oceans, potentially increasing this issue. Thus, collision avoidance regulations for the interaction of manned and unmanned vessels need to be developed (similar to what was done for manned vessels). To effectively implement these rules, an exchange of information between the interacting assets may be required. In this work, we will address the usage of JANUS, the first digital standard for underwater acoustic communications, and of the Automatic Identification System (AIS) to implement the exchange of possible messages, essential for collision avoidance. We will analyse how collision avoidance using underwater acoustic communications could work under different environmental conditions. An initial target scenario is considered where an active transmitter and a passive receiver are employed, including energy budget considerations. The conducted analysis shows that the proposed approach could be effectively applied when slow and fast vehicles are considered with both low and high power transmitters. To avoid possible collisions, the message transmission rate has to be set (adapted) properly depending on the considered configuration.