ACUA Ocean and Forssea Robotics have successfully completed a three-week demonstration programme in Plymouth that saw a remotely operated vehicle (ROV) deployed and controlled from an uncrewed surface vessel (USV), marking a significant step forward in remote subsea operations.
The trial brought together Forssea's ARGOS ROV and ACUA Ocean's Pioneer USV, with the underwater vehicle tracked using a Sonardyne Mini-Ranger 2 ultra-short baseline (USBL) positioning system. Throughout the campaign, all launch, recovery and dive activities were managed remotely from shore-based locations.
Operational control of the integrated system was carried out from ACUA Ocean's Remote Operations Centre at Turnchapel Wharf in Plymouth, while Forssea engineers monitored and supported activities remotely from the company's headquarters in Sète, France.
The project, undertaken under contract with the European Space Agency, aimed to assess whether inspection, survey and light-intervention tasks traditionally requiring crewed support vessels could instead be performed using an autonomous surface platform.
Successful ROV deployments
During the programme, the team completed more than 40 successful ROV deployments. On one occasion, eight separate launch and recovery operations were carried out within a single day. The ARGOS vehicle conducted seabed inspections in water depths exceeding 20 metres while operating with tether lengths of up to 35 metres.
A number of inspection targets were examined during the trials, including the wreck of the Poulmic, a seabed feature and a concrete reference block located in Cawsand Bay. The ROV successfully located and recorded footage of each target.
Testing was conducted in a range of environmental conditions. According to the companies, operations continued in sea states featuring one-metre waves and average wind speeds of 18 knots, with gusts reaching up to 30 knots. Additional work carried out south of Plymouth Breakwater in seas approaching two metres reportedly had no adverse impact on ROV performance.
Remote observation capabilities
To support underwater navigation, the Pioneer USV carried a Sonardyne Mini-Ranger 2 USBL system paired with a WSM6+ transponder fitted to the ARGOS vehicle. Both dynamic positioning and manual station-keeping techniques were employed to maintain the required operating position throughout missions.
The demonstration also showcased remote observation capabilities when a live ROV dive was streamed to the Cyber Innovation Hub of the Bundeswehr in Eckernförde, Germany, allowing stakeholders in another country to monitor operations taking place in UK waters.
"These trials prove we can open a weather window that conventional crewed vessels cannot work in, giving operators a wider weather window for inspection campaigns."
" Just as importantly, running inspection campaigns from an uncrewed surface vessel takes significant cost out of the work – fewer support vessels, fewer people offshore and far less weather-related downtime.”
- ACUA Ocean CEO Neil Tinmouth
"All of us at Forssea are hugely proud of this milestone and impressed by Pioneer’s sea-state capabilities."
"Seeing how smoothly the ROV integration and the multiple launch-and-recovery sequences went over the past few weeks was hugely satisfying. My congratulations to the ACUA engineering teams – we are excited to see what comes next."
- Gautier Dreyfus, CEO of Forssea Robotics
The companies are targeting offshore energy operators, subsea inspection and maintenance providers, critical infrastructure operators and survey organisations with the combined system.
ACUA Ocean describes Pioneer as an uncrewed surface vessel designed to provide endurance and seakeeping for remote maritime operations, while Forssea’s ARGOS is a compact ROV intended for inspection, survey and light-intervention work. Forssea supplied the underwater vehicle with a dedicated integration kit for use aboard the USV, allowing the two systems to operate as a single remotely supervised package. The ROV can also carry different payloads depending on the inspection or survey task being undertaken.
The project reflects a broader industry trend towards reducing reliance on large crewed support vessels for routine subsea work. By combining autonomous surface platforms with remotely controlled underwater vehicles, operators can perform inspection and monitoring activities with fewer people offshore while maintaining operational oversight from land-based control centres.
A key focus of the Plymouth campaign was demonstrating reliable launch and recovery procedures, maintaining communications and positioning between the two platforms, and proving that the integrated system could be operated effectively and safely from shore throughout a series of coastal-water missions.
