In the 1960s, Shell Oil and Hughes Aircraft developed a 14‑ft-long, 7,000‑lb manipulator-operated robot known as Mobot. The system was deployed to the seafloor and connected to operators on a surface vessel through a 200‑ft umbilical that provided power and a live video feed. State-of-the-art at the time, the technology was designed to reduce reliance on oilfield divers while extending operational depths beyond safe human limits, performing tasks such as valve and fitting manipulation on subsea wellheads.
When the technology debuted offshore Santa Barbara, California, it showed potential, but it also earned a reputation for getting tangled or failing for various reasons. The Mobot’s teething problems meant it often had to be pulled back up to the vessel and earned it the nickname “a diver’s best friend” since they were sometimes tasked with recovering the robot.
Despite its limitations, the Mobot remained in use on subsea wells for about 10 years and is credited with establishing the foundation for the oil and gas industry’s widespread adoption of remotely operated vehicles (ROV). A few decades on, the next progression of this technology arena seems poised to emerge as was shown in several technical papers presented at the recent Offshore Technology Conference (OTC) in Houston.
One paper that might impress the developers of the Mobot and truly underlines the recent advances in oilfield robotics, OTC 37170, comes from authors with Saipem. It describes a resident underwater intervention drone (UID) called the Hydrone-R that carried out subsea operations, including wellhead commissioning operations, offshore Norway from 2023 to 2025. The UID is described as a hybrid system that can be either human-operated or run in autonomous mode.
JPT covered its initial deployment at Equinor’s Njord-A field in this August 2025 article, but since then, Saipem’s UID racked up more than 400 combined days of operations with an availability rate of 99.9%. According to the authors, a single continuous deployment lasting 8 months set a new industry record for a UID. They added that the technology was still working in the subsea field when the paper was written.
Operating at water depths greater than 1,000 ft, the Hydrone-R performed work comparable to that of a conventional work-class ROV, including inspection and light intervention tasks, without requiring a dedicated support vessel. The argument for its value was most clearly made during periods when conventional ROVs were unavailable or unable to operate due to weather. At one point in the deployment, sea states exceeded 40-ft wave heights, conditions the authors note are beyond the operating limits of typical ROVs.
A second Saipem paper, OTC 37203, notes that an earlier version of the technology was piloted by Shell and Petrobras offshore Brazil from 2022 to 2023 and performed autonomous inspection missions at depths beyond 5,500 ft. The paper also presents the UID as a platform technology that can be coupled with an “internet of underwater things” and pipeline repair systems to become a new alternative for the industry’s emergency response strategies.
Another paper from authors at BP and industrial robotic company Avestec makes the case for using above-water robots to remove humans from high-risk inspections. Specifically, the paper speaks to inspections of riser-hull piping, found underneath offshore platform decks, with what are called “marsupial flying robots” that can deploy a mini-crawler robot.
The initial trial in 2025 was deemed a success in that it showed the unmanned aerial vehicle (UAV) was able to safely land and retrieve the crawler which uses magnets to stay attached to the platform. The crawler also used an electromagnetic acoustic transducer and multiple cameras to deliver measurements that the companies said closely matched human-captured results with ultrasonic testing. BP and its technology partner added that the UAV-based system required just two personnel, half that needed for traditional inspections beneath the platform floor.
Most of the papers on this topic presented at OTC show that the primary value driver for offshore robotics remains inspection, though there is an increasing degree of sophistication and utility across the examples offered this year.
OTC 37166, authored by remote inspection firm TSC Subsea, describes the use of robotic crawlers equipped with acoustic resonance sensors to inspect crude-oil-loading pipelines with geometries that made them inaccessible to conventional pigging tools. Using a tethered crawler, the operator obtained wall thickness data for the two 1.2-km pipelines which was used to support integrity assessment and life-extension decisions.
OTC 37093 furthers the point about inspection value by arguing that even greater value can be realized by integrating robotic inspection data with digital twins. Authored by ROV provider Deep Trekker, the paper says that while autonomously conducting inspection surveys, small subsea robots can also capture high-quality imagery that can be used to generate 3D models of offshore infrastructure.
In one case offshore Norway, the use of compact ROVs eliminated the need for divers, thus avoiding mobilization of a diver support vessel. The paper added that using specialized ROVs to obtain visual data lowers the cost of generating digital twins for subsea infrastructure while also allowing companies to depart from costly calendar-based schedules and instead adopt predictive maintenance strategies.
This sampling of examples suggests, at least according to the authors, that not only are offshore robots ready to take on a growing number of jobs, but that they can also do so cheaper and safer than many human-performed inspections. However, there is an argument to be made that robots are there to be tools for the offshore workforce—not necessarily replacements.
This is one of the points made in OTC 37015 by authors from Shell’s Brazil unit and one of Brazil’s biggest applied research centers, SENAI CIMATEC. The paper offers a comprehensive outline of how companies should approach research and development of robotics, and how they can be best integrated into the field where they must ultimately interact well with human workers.
The paper identifies several current value drivers. Aside from reduced inspection and repair costs, it cites lower nonproductive time, fewer safety-critical interventions, and improved asset‑integrity awareness. It also notes reductions in personnel exposure to safety risks and in greenhouse gas emissions since, as mentioned earlier, using small robots sometimes means that operators can forgo support vessels.
The authors also stress that R&D groups must incorporate input from field teams to improve deployment outcomes. In one example, the accelerated development of a topside inspection robot called Viper followed feedback from platform personnel on their challenges associated with working at heights, confined‑space access, personnel constraints, and inspection backlogs.
Trials done offshore Brazil on a Shell platform in 2025 led to some notable improvements, including a more intuitive assembly process, dedicated training programs, and adjustments to the robot’s commercial deployment strategy. Additional modifications that came from employee feedback included variable-length manipulators, higher-resolution cameras, increased battery capacity, and integration of electromagnetic acoustic transducers for wall thickness measurements.
If Mobot offers a lasting lesson, it is that where value can be increased and risk reduced, development tends to follow. Advanced offshore robotics may still be in the early stages, but these recent deployments show they are increasingly capable of playing a larger role in inspection and intervention work with varying degrees of autonomy. Even so, they also show us that consistent field performance appears to still very much depend on sound human oversight and judgment.
For Further Reading
OTC 37021 Above-Water Riser Visual and EMAT Inspection Using a Marsupial Flying Robot With UAV- Deployed Mini Crawler by J. Lou, BP, and R. Tavakoli, Avestc, et al.
OTC 37166 Enabling Life Extension of Unpiggable Crude Oil Pipelines Using Robotic Crawlers and Acoustic Resonance Technology by P. Chittenden, B. Davey, M. Keynes, and J.O. Toskedal, TSC Subsea.
OTC 37170 Lesson Learnt From Resident Robotics: How To Solve Daily Issues While Improving Project Economics by F. Cavallini, L. Turi, and G. Massari, Saipem.
OTC 37203 Surveillance of Subsea Pipelines: The Role of Underwater Robotics for Critical Assets by F. Cavallini and G. Massari, Saipem.
OTC 37093 Scalable Digital Twin Workflows With Subsea Robotics for Offshore Integrity Management by S. Browns, Deep Trekker.
OTC 37015 Robots as Strategic Tools–A New Approach to Portfolio Development Integrating Basic and Applied Research for Faster Field Deployment by D. Juliano, C. Lima, L. Pinheiro, and N. Monteiro, Shell Brasil, et al.
