Operating uncrewed surface vehicles (USVs) over-the-horizon (OTH) using satellite communications increases efficiency and flexibility, however it also requires additional consideration for safe and reliable operation. Before compact, high bandwidth satellite telemetry systems were available, USVs were limited to marine radios with a maximum range of approximately 20 kms (contingent on weather and height of antennas) requiring operators to be in the immediate vicinity. During OTH operations, USV watch standers (pilots and mappers) operate vehicles from offsite remote operations centers (ROCs), which may be anywhere on the globe. University of New Hampshire’s Center for Coastal and Ocean Mapping (CCOM) autonomous systems group has installed Starlink satellite systems on their Drix and C-Worker USVs, to begin developing technology and methods to address the challenges of safe OTH operations. Lessons learned include the fact that USVs must be sufficiently reliable to ensure that costly and time-consuming recoveries are rarely required, particularly when operating in remote areas. If satellite communications are compromised, USVs operating OTH require more autonomy must have the ability to safely transit unsupervised, or minimally supervised, to safe harbor, relying solely on the vehicle’s perception system. Thus USVs must have the ability to self-diagnose problems with critical navigational equipment. Finally, all operators, onsite and offsite, need to have reliable and backup methods of communication. These and other lessons from past operations will be discussed.

The drive to use Uncrewed Surface Vessels (USVs) to conduct geophysical survey operations is being led by the energy companies involved in Offshore Wind & Carbon Capture & Storage and consequently being used in Oil & Gas operations too. At XOCEAN we have developed Uncrewed Surface Vessel (USV) technology with the prime aim of collecting ocean data in a sustainable manner. Currently, our expanding fleet comprises over 25 USVs, with production slated for significant growth in the upcoming year(s). This expansion enhances our capacity to deploy multiple USVs simultaneously on survey projects. The USV(s) are capable of full “over-the-horizon” operations without a support vessel. In this presentation, we will showcase examples of surveys conducted using a flotilla of USVs, demonstrating the benefits and addressing some of the constraints encountered, along with the strategies employed to overcome them.

With the growing emphasis at the national and international level to accurately map the global oceans to modern standards, the rapidly evolving development of uncrewed systems will play an increasingly important role in reaching these goals. In 2022 and 2023, Saildrone Surveyor SD-1200 completed a first-of-its-kind bathymetric and oceanographic survey of the Aleutian Islands, proving the effectiveness of using a long-endurance autonomous system to collect high-resolution MBES survey data in remote, deep-water areas. With this successful first-of-class demonstration, Saildrone took on the challenge of employing similar high-resolution multibeam equipment in a mid-size, long-endurance uncrewed vehicle for operating in the much more congested area of the continental shelf. Combining the Saildrone Voyager USV, a newly developed 10m (33’) class of vehicle using patented wind-propulsion, solar-powered technology, with the well-proven Norbit Winghead series of multibeam echosounders, Saildrone was able to field a system capable of long-endurance, 24/7 survey operations in continental shelf water depths to IHO Order 1 and above standard. This system was employed on a mapping project for the first time on the Gulf of Maine, collecting data for habitat characterization. The development and integration process, as well as results from system testing and validation, will be presented along with the results of the first phase of a large-scale mapping mission. The results of continued optimization of the sonar equipment by Norbit Subsea aimed at increasing survey efficiency in the deepest parts of the continental shelf will also be discussed, along with trial results on the newest generation of Voyager USV. Additionally, the command-and-control functionality of Saildrone’s unique Mission Portal for bathymetric operations will be demonstrated.

During 2023, Ocean Infinity’s Australia and New Zealand Team successfully completed two nautical charting projects for Land information New Zealand (LINZ) and Australia’s HydroScheme Industry Partnership Programme (HIPP) using a three-vessel solution including two DriX USVs. The projects surveyed a total of almost 15,000 nautical line miles split between the MV Seaworker mothership and the two DriX. The projects were a first of their kind for Ocean Infinity, with the DriX being controlled from on-board the Seaworker, delivering a three-vessel solution in line with our goal to increase efficiency and sustainability in operations at sea, collecting more data over a shorter time and reducing the environmental impact of the survey. The projects have proved the capability of USVs for nautical charting operations and will act as a springboard for Ocean Infinity’s wider Armada fleet.

The Center for Coastal and Ocean Mapping at the University of New Hampshire owns and operates “DriX-8”, an Uncrewed Surface Vehicle (USV) manufactured by Exail and funded by NOAA’s Office of Ocean Exploration and Research through the Ocean Exploration Cooperative Institute. The DriX vehicle was designed for acoustic survey operations, providing a high-endurance platform with hydrographic grade navigation systems and a subsea gondola for sonars. As delivered, DriX-8 was equipped with a Kongsberg EM2040 with typical full-swath capability to water depths of 200-300 m. NOAA expressed interest in future survey operations to depths exceeding 1000m and encouraged integration of a suitable sonar. Kongsberg’s re-design of their EM712 and its integration by Exail into the gondola of the DriX will be described. Data will be shown from factory and sea acceptance testing, along with preliminary operational surveys. The re-packaged EM712 installed aboard the DriX is found to produce usable data to depths exceeding 3000m, with some reduction in swath width, due to increased flow and/or propeller noise at speed at all depths.

Today’s most advanced uncrewed surface vessels (USVs) are more capable than ever and are close to achieving the dream of truly autonomous force multiplication. Many of the features that make these new vessels so advanced relate to technologies enabling more sophisticated navigation and autonomy which are not present in the vast majority of the USV fleet. Some of these advances in navigation and autonomy can however, be brought to nearly any vessel in the existing USV fleet using simple, low-cost components. Though the exact method may vary, most USVs must be individually controlled through a dedicated control link. The Ocean Mapping Group at the University of New Brunswick is pursuing an alternative control method using mobile ad hoc networks to allow a multi-vessel swarm of any number of USVs to communicate with each other and back to a control station. Additionally, this network can be leveraged to allow a shared real time hierarchical data model to be updated and used by all vessels for decision-making about navigation and quality assurance. While today’s USVs are closing the gap to true autonomy, force multiplication can still be achieved on nearly any existing or less sophisticated USV by implementing this innovative swarm control method. thereby accessing their latent potential. The implementation of a method for sharing data between multi-vessel swarms in real time to allow for autonomous decision-making on navigation and quality assurance ensures the many existing USVs will continue to be important tools for hydrospatial data collection.