Case Study: DOF Subsea achieves accurate, low-complexity shallow-water ROV positioning with Advanced Navigation Subsonus USBL/INS

DOF Subsea Selects Subsonus USBL/INS for Their Small-Scale ROV

DOF Subsea, an international subsea services organization, needed a compact and accurate way to position a very small ROV for shallow-water pipeline surveys off Western Australia. In water as shallow as 10 to 15 meters, traditional USBL systems were affected by noise and reflections, creating errors of up to 15 meters and making it difficult to survey safely without adding size, complexity, or cost. Advanced Navigation’s Subsonus USBL/INS was selected as the positioning solution.

Advanced Navigation deployed dual Subsonus units with a GNSS Compass on the surface vessel and a third-party DVL on the ROV, giving DOF Subsea integrated USBL positioning, INS, acoustic heading transfer, and velocity input in a compact setup. The system delivered stable sub-meter accuracy, with the team expecting about 0.4 m tolerance at depth and reporting positioning remained accurate even as the ROV ran out of tether; the integrated design also reduced equipment modules, simplified installation, and avoided the need for a separate FOG heading source, cutting cost and deployment complexity.

DOF Subsea

Gavin Wallace

Project Surveyor