The water column is hazy as an unusual remotely operated vehicle glides over the seafloor in search of a delicate tilt meter deployed three years ago off the west side of Vancouver Island. The sensor measures shaking and shifting in continental plates that will eventually unleash another of the region’s 9.0-scale earthquakes (the last was in 1700). Dwindling charge in the instruments’ loggers threatens the continuity of the data.
The 4-metric-ton, C$8-million (US $5.8-million) remotely operated vehicle (ROV) is 50 meters from its target when one of the seismic science platforms appears on its sonar imaging system, the platform’s hard edges crystallizing from the grainy background like a surgical implant jumping out of an ultrasound image. After easing the ROV to the platform, operators 2,575 meters up at the Pacific’s surface instruct its electromechanical arms and pincer hands to deftly unplug a data logger, then plug in a replacement with a fresh battery.
This mission, executed in early October, marked an exciting moment for Josh Tetarenko, director of ROV operations at North Vancouver-based Canpac Marine Services. Tetarenko is the lead designer behind the new science submersible and recently dubbed it Jenny in homage to Forrest Gump, because the fictional character named all of his boats Jenny. Swapping out the data loggers west of Vancouver Island’s Clayoquot Sound was part of a weeklong shakedown to test Jenny’s unique combination of dexterity, visualization chops, power, and pressure resistance.
Jenny is only the third science ROV designed for subsea work to a depth of 6,000 meters.
By all accounts Jenny sailed through. Tetarenko says the worst they saw was a leaky O-ring and the need to add some spring to a few bumpers. “Usually you see more things come up the first time you dive a vehicle to those depths,” says Tetarenko.
Jenny’s successful maiden cruise is just as important for Victoria, B.C.–based Ocean Networks Canada (ONC), which operates the NEPTUNE undersea observatory. The North-East Pacific Time-series Undersea Networked Experiments array boasts thousands of sensors and instruments, including deep-sea video cameras, seismometers, and robotic rovers sprawled across this corner of Pacific. Most of these are connected to shore via an 812-kilometer power and communications cable. Jenny was custom-designed to perform the annual maintenance and equipment swaps that have kept live data streaming from that cabled observatory nearly continuously for the past 15 years, despite trawler strikes, a fault on its backbone cable, and insults from corrosion, crushing pressures, and fouling.
NEPTUNE remains one of the world’s largest installations for oceanographic science despite a proliferation of such cabled observatories since it went live in 2009. ONC’s open data portal has over 37,000 registered users tapping over 1.5 petabytes of ocean data—information that’s growing in importance with the intensification of climate change and the collapse of marine ecosystems.
Over the course of Jenny’s maiden cruise, her operators swapped devices in and out at half a dozen ONC sites, including at several of NEPTUNE’s five nodes and at one of NEPTUNE’s smaller sister observatories closer to Vancouver.
Inside Jenny
ROV Jenny aboard the Valour, Canpac’s 50-meter offshore workhorse, ahead of October’s NEPTUNE observatory maintenance cruise.Ocean Networks Canada
What makes Jenny so special?
- Jenny is only the third science ROV designed for subsea work to a depth of 6,000 meters.
- Motion sensors actively adjust her 7,000-meter-long umbilical cable to counteract topside wave action that would otherwise yank the ROV around at depth and, in rough seas, could damage or snap the cable.
- Dual high-dexterity manipulator arms are controlled by topside operators via a pair of replica mini-manipulators that mirror the movements.
- Each arm is capable of picking up objects weighing about 275 kilograms, and the ROV itself can transport equipment weighing up to 3,000 kg.
- 11 high-resolution cameras deliver 4K video, supported by 300,000 lumens of lighting that can be tuned to deliver the soft red light needed to observe bioluminescence.
- Dual multibeam sonar systems maximize visibility in turbid water.
Meghan Paulson, ONC’s executive director for observatory operations, says the sonar imaging system will be particularly invaluable during dives to shallower sites where sediments stirred up by waves and weather can cut visibility from meters to centimeters. “It really reduces the risk of running into things accidentally,” says Paulson.
To experience the visibility conditions for yourself, check out recordings of the live video broadcast from the NEPTUNE maintenance cruise. Tetarenko says that next year they hope to broadcast not only the main camera feed but also one of the sonar images.
3D video could be next, according to Canpac ROV pilot and Jenny codesigner, James Barnett. He says they would need to boost the computing power installed topside, to process that “firehose of data,” but insists that real-time 3D is “definitely not impossible.” Tetarenko says the science ROV community is collaborating on software to help make that workable: “3D imagining is kind of the very latest thing that’s being tested on lots of ROV systems right now, but nobody’s really there yet.”
More Than Science
Expansion of the cabled observatory concept is the more certain technological legacy for ONC and NEPTUNE. In fact, the technology has evolved beyond just oceanography applications.
ONC tapped Alcatel Submarine Networks (ASN) to design and build the Neptune backbone and the French firm delivered a system that has reliably delivered multigigabit Ethernet plus 10 kilovolts of direct-current electricity to the deep sea. Today ASN deploys a second-generation subsea power and communications networking solution, developed with the Norwegian international energy company Equinor.
ASN’s “Direct Current/Fiber Optic” or DC/FO system provides the 100-km backbone for the ARCA subsea neutrino observatory near Sicily, in addition to providing control systems for a growing number of offshore oil and gas installations. The latter include projects led by Equinor and BP where DC/FO networks drive the subsea injection of captured carbon dioxide and monitor its storage below the seabed. Future oil and gas projects will increasingly rely on the cables’ power supply to replace the hydraulic lines that have traditionally been used to operate machinery on the seafloor, according to Ronan Michel, ASN’s product line manager for oil and gas solutions.
Michel says DC/FO incorporates important lessons learned from the Neptune installation. And the latter’s existence was a crucial prerequisite. “The DC/FO solution would probably not exist if Neptune Canada would not have been developed,” says Michel. “It probably gave confidence to Equinor that ASN was capable to develop subsea power and coms infrastructure.”
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