VESSEL REVIEW | Arctos 1 – Hybrid USV for windfarm inspections in Baltic Sea

Polish marine data company Blue Armada Robotics has entered into a partnership with UK-based uncrewed surface vessel (USV) manufacturer HydroSurv. As part of this collaboration, Blue Armada has acquired its first USV from HydroSurv, which will be used to serve clients in the uncrewed marine data collection market in the Baltic Sea.

Named Arctos 1 after the Latin for “bear,” the USV belongs to a series of multi-purpose platforms that also offer long-endurance, beyond visual line of sight (BVLOS) capability for a wide range of applications.

Constructed under survey by Lloyd's Register to a Special Service Craft (SSC) compliant design, the USV is ideally suited to self-transiting campaigns within hydrographic, oceanographic, and environmental data collection or offshore asset inspection.

Compact hull compatible with a range of sensor payloads

The USV boasts a length of six metres (20 feet) and multi-day endurance with a battery hybrid powertrain. Its 200kg payload capacity allows for a diverse range of onboard equipment, including inspection-class remotely operated vehicle (ROV) systems.

The principal dimensions enable the craft to be transported, launched, and recovered by road trailer, while its modular construction enables the entire system to be housed inside a standard shipping container for rapid global mobilisation.

Extensive hydrostatic and hydrodynamic analysis led to the selection of a symmetrically-hulled, welded aluminium catamaran design that blends energy efficiency with excellent seakeeping characteristics and satisfies the freeboard and stability requirements prescribed within the UK Workboat Code.

The optimised hull is designed to perform well in offshore environments, whilst the subdivision enables the vessel to satisfy damage stability cases. Enhanced manoeuvrability and station keeping ability are meanwhile both possible thanks to two 3.8kW electric pod motors that can be steered independently.

Hybrid propulsion ensuring long endurance

The craft’s hybrid powertrain consists of a 6kW diesel generator and 22kWh lithium batteries. Even at maximum load, the USV uses up just two litres (0.4 gallon) of fuel per hour, allowing it to conduct sustained operations at sea.

The USV also boasts HydroSurv’s proprietary command and control system. Redundancy and watchdog features are embedded into an architecture that provides control and monitoring of multiple shipboard systems and mission-specific equipment.

HydroSurv has also implemented a number of intelligent optimisations into the hybridisation control. These include the ability to geofence “quiet zones” within the front end system to reduce underwater radiated noise at certain points during the mission and the ability to arrive at certain waypoints with the batteries fully charged.

Blue Armada intends to acquire several more USVs from HydroSurv in the next year. These craft will initially be used for remote inspection of offshore wind farms in Poland.

Future duties will include pre- and post-construction surveys such as multibeam echosounder (MBES) surveys, unexploded ordnance (UXO) surveys, sub-bottom profile (SBP) surveys, and side-scan sonar (SSS) surveys. The craft will also be utilised for cyclic and on-demand asset supervision with balance-of-plant integrity checks including, but not limited to, foundations, monopiles, jackets, and inter-array and export cables.

Arctos 1 will enable real-time data transmission, including from multi-beam sonars and close-to-object imagery, directly to asset-owning clients and suppliers both domestically and internationally. The USV was delivered in July 2024, and demonstrations in the Baltic Sea are planned for later this year.