Systems and technologies for multi-domain synoptic ocean observation

A systems approach to synoptic ocean observation on the sub-mesoscales is presented and results of field studies are discussed. The approach builds on innovative open-source communication and autonomy software developed by LSTS-Porto University that enables networked unmanned underwater, surface and air vehicles, as well as oceanographic vessels, to find, track, and sample dynamic features of the ocean with adaptive spatial and temporal resolutions.

The LSTS software toolchain enables the provision of: 1) distributed acoustic and radio communications infra-structure to support the coordination and control of all assets; 2) inter-operability framework to support all components of the system; 3) on-board Artificial Intelligence (AI) based planning and execution control capabilities (to allow autonomous underwater vehicles (AUV), unmanned air vehicle vehicles (UAV), and autonomous surface vehicles (ASV) to perform complex sampling tasks, cooperatively or isolated, in communications-challenged environments; 4) off-board mixed initiative planning and execution control capabilities for the integrated multi-vehicle system enabling remote participation, ocean space management, and adaptation to intermittent, low bandwidth, and delayed communications; and , 5) new UAV- and AUV-based sampling methods for targeted synoptic observations.

The approach was demonstrated in 2018 during the Exploring Fronts with Multiple Robots Schmidt Ocean Institute cruise. The cruise targeted the study of the Northern Pacific Subtropical Front (STF) with the R/V Falkor and multiple underwater, surface and air vehicles. We performed a mesoscale mapping of the front to identify sampling hotspots. In these spots we performed high-resolution surveys with other AUVs, equipped with physical and biological sensors, complemented with ship-based measurements and water sampling. Vertical Take-Off and Landing (VTOL) UAVs were tasked to fly over transects made over these hotspots to collect IR, multi-spectral and visible light imagery, as well as to measure concentrations of DMS in the air (DMS is a proxy for some types of biological activities that may take place at fronts). Coordinated ship-robotic survey were also conducted during this phase. In these surveys, the R/V Falkor, two or three AUVs, and one UAV moved in formation, with speed adjustments for the UAV, to sample the air and the ocean at selected hotspots.