26 July 2013
Inside the ROPOS Control Room
At any given moment during a dive mission, the remotely operated vehicle (ROV) control room on the R/V Thompson can be populated by ten or more people. With the lights turned low, the room is lit by the glare of a dozen flat-panel screens in easy view of everyone present. Some display information for navigation, allowing the dive team to quickly pinpoint their position on a map. Others are fed video directly from cameras on the ROV, providing a comprehensive field of vision for the pilot. Still others are dedicated to sonar imaging, sensor data, or displays of pressure gauges on the ROV, updating those present with real-time information relevant to the mission. It’s a complicated array of information, expertly managed by a team of professionals.
Meet the ROPOS crew, a world-class undersea research group hailing from Canada. Working around the clock, they maintain and operate an undersea robotic vehicle the size of a Volkswagen bug. To say that they are capable is an understatement - with decades of combined experience under their belt, the crew works seamlessly to deploy instrumentation and lay kilometers of cable. All this while the machine runs at 1,500 meters and more under the surface of the Pacific, where even a faulty camera feed can cause a tragic conclusion to a mission. Right now, they’re working in partnership with the National Science Foundation’s Ocean Observatories Initiative's regional cabled observatory program, an unprecedented attempt to provide power and bandwidth to distributed sensor arrays throughout the ocean. Working some 300 miles off the Oregon coast, the ROPOS ROV deploys ocean-bottom seismometers, bottom pressure tilts, and node infrastructures to sites that include actively venting hydrothermal vent fields. To put it simply, they’re wiring the ocean. Real-time data from remote instruments will stream to shore at 240 gigabits per second and will be made available online.
I came aboard the Thompson last week, at the beginning of the third leg of the cruise. Having been involved in the construction of small ROVs since junior high school, I was excited to see the ROPOS team in action. Before I knew it, I was sitting at the logging station in the control room, watching the ROV being deployed by crane into the waves of the Pacific Ocean. The time was 4AM, and I held a warm cup of coffee. My watch partner, Isaac, sat next to me, staring up at a monitor displaying a live feed of the crane. ROPOS looked alien as it was lowered into the water, a beacon of lights in the dark pool of water. A pilot communicated information from the control room to the crane operator via walkie talkie. Finally, the ROV slipped under the surface, and the lights faded as it sank into the depths.
It takes an hour for ROPOS to descend to its landing site - 1,500 meters is about a mile. As the machine drops through the water column, there is little to be seen except for the occasional fish. The ROPOS crew turns on some music and plans their mission during the trip to the seafloor, while Isaac and I familiarize ourselves with the logging software. Our job is to record, both visually and verbally, each event as it unfolds. The information we produce is immediately uploaded to a network, where it can later be combed for useful data. A copy of the dive plan lies on the table, telling us that today we’re deploying 1,400 meters of cable and surveying potential deployment sites. Finally, we reach the seafloor, and the monitors become windows into another world. What can I say to adequately describe these hydrothermal vent sites? The ground is composed of hardened lava flow, a dark backdrop to scuttling spider crabs and meandering ratfish. Nearby at the ASHES hydrothermal vent site, life teems and thrives around hot, mineral liquid forced into the water column. ROPOS appears to be a giant mothership in this environment, a moving platform of lights and dangling manipulator arms. The sea creatures don’t seem to mind, though: We stop occasionally to observe the fascinating life forms around us. I feel as if I’m actually present at the bottom of the ocean, and it is a privilege.
“Mark this area,” says the mission commander. The navigator calls back: “5.7 degrees tilt.” Some of it goes over my head, but I input the actions of the ROV into my computer. The ROPOS machine is equipped with two hydraulic arms, appendages that move with surprising dexterity. Two bench-top, replica-sized versions of the arms sit in the control room, stuck onto platforms. Now a pilot picks one up, sets it in his lap, and begins maneuvering it, and the hydraulic arm on ROPOS mimics its movement. He uses it to pluck a marker from a holding container and set it down on a level spot on the seafloor. Later, we will return to this site to deploy an instrument.
The ROPOS vehicle is attached to the Remotely Operated Cable Laying System, or ROCLS (pronounced rock-uhls). Essentially, it’s a giant automated spool that pays out cable as the ROV drives forward. The rest of today’s mission consists of paying out the entire spool of cable, a process that must be completed carefully to ensure that no slack is wasted on our route. We begin, counting each layer in the spool as it unfolds and comparing it to the expected payout of cable. If we use too much, the cable might not reach its destination - not a disaster, but a painful problem to fix. As we drive, the navigator communicates with the bridge. The ship’s pilot follows our route, keeping the Thompson directly above the ROPOS vehicle. It may take a village to raise a child, but it takes a crack team of engineers and crew to run an ROV. There is constant communication between the ROPOS team and the deck crew, between the control room and the bridge, and between the scientists and the ROV pilots. The end result is a well-executed mission.
Before I know it, my watch is over. Isaac and I pass things off to the next logging crew; the mission is far from concluded. I will eat breakfast, get some sleep, and do it all over again tomorrow.
I came away from my first logging experience impressed at the enormity of it all, at the complexity of information and communication that takes place inside the ROPOS control room. The operation is like a well-oiled machine, old hat to many of those who operate the ROV. I am impressed with the decades of engineering that led up to this moment in time, allowing us not only to dive to the bottom of the ocean but to know where we are on a GPS grid. I am grateful to those who had the vision to make this program a reality, and not just because I was invited to participate: I believe that what we are doing here is very important. The scope of the OOI regional cabled observatory program is unprecedented, and a deeper understanding of these hydrothermal systems is a crucial stepping stone on our path to understanding the ocean environment. At the center of it all is the control van, the workhorse of the cabled observatory program. Without this epicenter, we could not have accomplished all that we have, nor hope to accomplish all that we plan to do. Hats off to the ROPOS control room.