Saipem’s Hydrone ROV looks to make the best of both worlds
While some subsea robotics firms are working on vehicles capable of travelling hundreds of miles, those in the inspection, maintenance and repair (IMR) market are working on solutions that stick closer to home – but are by no means less adventurous.
Advances in subsea power infrastructure, battery life and communications are ushering in a new wave of subsea-resident options, a few of which this issue of InnovOil will examine. As that happens, traditional categories begin to break down, as is evidenced by the latest technology trailered by Saipem.
Developed by its somewhat secretive Sonsub unit, Saipem’s Hydrone robot is tricky to pin down. In a recent interview with Upstream Technology, Sonsub’s manager of remote control systems, Paolo Bonel, was emphatic, maintaining that “this not an AUV” but a new kind of hybrid – an autonomous ROV.
More clarity is offered by a recent promotional video issued by the company. Hydrone appears to combine a multitude of typical subsea technologies in one versatile platform. Although it may resemble a traditional light work-class ROV with two manipulator arms, it is able to operate tethered and untethered, human-piloted and autonomous. Saipem is betting on this flexibility as the future of subsea installation maintenance, using a robot that can adapt to each task as required.
The scope needed to achieve this is by no means limited. The company intends to harness a new kind of communications system based on optical, acous
tic and electromagnetic signals, creating essentially a subsea wi-fi network. “We are developing a multi-mode modem that is able to manage these three physical communication systems and to automatically switch, or distribute the data, through these three different physical channels so that you have a more reliable connection and more bandwidth in the communication,” Bonel told the publication.
One for all The demonstration video gives a better idea of what this could mean in practice. In one instance, a tethered Hydrone surveys a manifold before grabbing a torque tool skid to operate a valve. In another, human operators initiate an autonomous survey of a flowline, which is then carried out independently by a battery-powered, untethered system. After completing the survey, an operator can pilot the ROV back to base to recharge. A final scenario envisions a leak or alarm scenario, allowing operators to dispatch a tethered system to inspect and monitor the situation, and intervene to turn a shutdown valve.
The Marghera-based unit intends to develop three distinct variations of the craft: the Hydrone-S, which would handle “advanced survey work”; a subsea-resident variation dubbed Hydrone-R; and the Hydrone-W, a battery-powered ROV that would be operated from shore.
Although the Hydrone concept is not entirely on its own, there are few platforms aiming for the same level of versatility as Sonsub, and perhaps even fewer heading towards actual trials. Perhaps that reflects the level of innovation required to put the system in the water.
These technologies are also to be included in another of Saipem’s ongoing ROV projects, Innovator 2.0. This is a heavy work-class system redesigned from the seafloor up, and for which sea trials were completed late in 2016. Although designed to be tethered to a vessel, this ROV includes a 6,600V power supply, allowing it to operate even with extremely long cable lengths of over 7,000 m. A 210HP electrical motor and high efficiency propulsion system gives the unit a bollard pull of 1,100 kg in either direction, a maximum speed of 3.5 knots and a lift capacity of over 600 kg.
A prototype Hydrone is scheduled to begin trials in in 2018. We will keep readers informed as a new vanguard of hybrid ROVs begins to take shape.