Unmanned Seafloor Survey System Without Support Vessel and its Recent Operations in Sea Trials

As the future seafloor survey system without a support vessel, combinations of autonomous underwater vehicles (AUVs) and autonomous surface vehicles (ASVs) are expected. To realize ship-less operations, we have designed unmanned survey systems which consists of multiple AUVs, AUV towing frames, and an ASV. The ASV of the proposed system works as two roles: transporting AUVs between a shore base and a survey site, and relaying the communication between AUVs and a ground-based mission control. We have developed and tested the two sets of the proposed survey system. The first one is the survey system for 2,000m depth consists of three AUVs supervised by an ASV and the second one was for 4,000m depth consists of two AUVs supervised by the ASV. In this paper, we respectively introduce the two sets of the system design and also report the implementation and results of recent sea-trials in Suruga Bay.