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  • richardmitnick 11:58 am on January 30, 2019 Permalink | Reply
    Tags: , Algorithm could help autonomous underwater vehicles explore risky but scientifically-rewarding environments, , , , Engineers program marine robots to take calculated risks, , Undersea Exploration   

    From MIT News: “Engineers program marine robots to take calculated risks” 

    MIT News
    MIT Widget

    From MIT News

    January 30, 2019
    Jennifer Chu

    MIT engineers have now developed an algorithm that lets autonomous underwater vehicles weigh the risks and potential rewards of exploring an unknown region.
    Image: stock image.

    Algorithm could help autonomous underwater vehicles explore risky but scientifically-rewarding environments.

    We know far less about the Earth’s oceans than we do about the surface of the moon or Mars. The sea floor is carved with expansive canyons, towering seamounts, deep trenches, and sheer cliffs, most of which are considered too dangerous or inaccessible for autonomous underwater vehicles (AUV) to navigate.

    But what if the reward for traversing such places was worth the risk?

    MIT engineers have now developed an algorithm that lets AUVs weigh the risks and potential rewards of exploring an unknown region. For instance, if a vehicle tasked with identifying underwater oil seeps approached a steep, rocky trench, the algorithm could assess the reward level (the probability that an oil seep exists near this trench), and the risk level (the probability of colliding with an obstacle), if it were to take a path through the trench.

    “If we were very conservative with our expensive vehicle, saying its survivability was paramount above all, then we wouldn’t find anything of interest,” says Benjamin Ayton, a graduate student in MIT’s Department of Aeronautics and Astronautics. “But if we understand there’s a tradeoff between the reward of what you gather, and the risk or threat of going toward these dangerous geographies, we can take certain risks when it’s worthwhile.”

    Ayton says the new algorithm can compute tradeoffs of risk versus reward in real time, as a vehicle decides where to explore next. He and his colleagues in the lab of Brian Williams, professor of aeronautics and astronautics, are implementing this algorithm and others on AUVs, with the vision of deploying fleets of bold, intelligent robotic explorers for a number of missions, including looking for offshore oil deposits, investigating the impact of climate change on coral reefs, and exploring extreme environments analogous to Europa, an ice-covered moon of Jupiter that the team hopes vehicles will one day traverse.

    “If we went to Europa and had a very strong reason to believe that there might be a billion-dollar observation in a cave or crevasse, which would justify sending a spacecraft to Europa, then we would absolutely want to risk going in that cave,” Ayton says. “But algorithms that don’t consider risk are never going to find that potentially history-changing observation.”

    Ayton and Williams, along with Richard Camilli of the Woods Hole Oceanographic Institution, will present their new algorithm at the Association for the Advancement of Artificial Intelligence conference this week in Honolulu.

    A bold path

    The team’s new algorithm is the first to enable “risk-bounded adaptive sampling.” An adaptive sampling mission is designed, for instance, to automatically adapt an AUV’s path, based on new measurements that the vehicle takes as it explores a given region. Most adaptive sampling missions that consider risk typically do so by finding paths with a concrete, acceptable level of risk. For instance, AUVs may be programmed to only chart paths with a chance of collision that doesn’t exceed 5 percent.

    But the researchers found that accounting for risk alone could severely limit a mission’s potential rewards.

    “Before we go into a mission, we want to specify the risk we’re willing to take for a certain level of reward,” Ayton says. “For instance, if a path were to take us to more hydrothermal vents, we would be willing to take this amount of risk, but if we’re not going to see anything, we would be willing to take less risk.”

    The team’s algorithm takes in bathymetric data, or information about the ocean topography, including any surrounding obstacles, along with the vehicle’s dynamics and inertial measurements, to compute the level of risk for a certain proposed path. The algorithm also takes in all previous measurements that the AUV has taken, to compute the probability that such high-reward measurements may exist along the proposed path.

    If the risk-to-reward ratio meets a certain value, determined by scientists beforehand, then the AUV goes ahead with the proposed path, taking more measurements that feed back into the algorithm to help it evaluate the risk and reward of other paths as the vehicle moves forward.

    The researchers tested their algorithm in a simulation of an AUV mission east of Boston Harbor. They used bathymetric data collected from the region during a previous NOAA survey, and simulated an AUV exploring at a depth of 15 meters through regions at relatively high temperatures. They looked at how the algorithm planned out the vehicle’s route under three different scenarios of acceptable risk.

    In the scenario with the lowest acceptable risk, meaning that the vehicle should avoid any regions that would have a very high chance of collision, the algorithm mapped out a conservative path, keeping the vehicle in a safe region that also did not have any high rewards — in this case, high temperatures. For scenarios of higher acceptable risk, the algorithm charted bolder paths that took a vehicle through a narrow chasm, and ultimately to a high-reward region.

    The team also ran the algorithm through 10,000 numerical simulations, generating random environments in each simulation through which to plan a path, and found that the algorithm “trades off risk against reward intuitively, taking dangerous actions only when justified by the reward.”

    A risky slope

    Last December, Ayton, Williams, and others spent two weeks on a cruise off the coast of Costa Rica, deploying underwater gliders, on which they tested several algorithms, including this newest one. For the most part, the algorithm’s path planning agreed with those proposed by several onboard geologists who were looking for the best routes to find oil seeps.

    Ayton says there was a particular moment when the risk-bounded algorithm proved especially handy. An AUV was making its way up a precarious slump, or landslide, where the vehicle couldn’t take too many risks.

    “The algorithm found a method to get us up the slump quickly, while being the most worthwhile,” Ayton says. “It took us up a path that, while it didn’t help us discover oil seeps, it did help us refine our understanding of the environment.”

    “What was really interesting was to watch how the machine algorithms began to ‘learn’ after the findings of several dives, and began to choose sites that we geologists might not have chosen initially,” says Lori Summa, a geologist and guest investigator at the Woods Hole Oceanographic Institution, who took part in the cruise. “This part of the process is still evolving, but it was exciting to watch the algorithms begin to identify the new patterns from large amounts of data, and couple that information to an efficient, ‘safe’ search strategy.”

    In their long-term vision, the researchers hope to use such algorithms to help autonomous vehicles explore environments beyond Earth.

    “If we went to Europa and weren’t willing to take any risks in order to preserve a probe, then the probability of finding life would be very, very low,” Ayton says. “You have to risk a little to get more reward, which is generally true in life as well.”

    This research was supported, in part, by Exxon Mobile, as part of the MIT Energy Initiative, and by NASA.

    See the full article here .

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  • richardmitnick 7:11 pm on September 15, 2015 Permalink | Reply
    Tags: , , , Undersea Exploration   

    From NYT: “Do Humans Have a Future in Deep Sea Exploration?” 

    New York Times

    The New York Times

    SEPT. 14, 2015

    Terry Kerby, the head of the Hawaii Undersea Research Laboratory, peers through the porthole of a Pisces V research submarine. Credit Kent Nishimura for The New York Times

    Entering the Hawaii Undersea Research Laboratory hangar is akin to stepping onto the set of a Spielberg film. The dull metal shell, perched on the Makai pier along the Windward Coast of Oahu, is nondescript, but the inside bristles with Zodiac boats and a dizzying assortment of hoists and tools, and the walls are festooned with 30 years of snapshots. At the center of it all, two 20-foot-long Pisces submarines sit atop skids like alien spacecraft, their robotic arms outstretched, beckoning for another mission.

    The laboratory, part of the University of Hawaii and better known as HURL, has been the sole submersible-based United States deep-sea research outpost in the mid-Pacific since the 1980s.

    U Hawaii Undersea Research Lab - HURL

    U Hawaii bloc

    At its helm is Terry Kerby, perhaps the most experienced submersible pilot alive. With a crew of five, Mr. Kerby and the Pisces subs have discovered more than 140 wrecks and artifacts, recovered tens of millions of dollars in lost scientific equipment, and surveyed atolls and seamounts whose hydrothermal vents and volcanoes were unknown.

    Temp 1
    The Pisces IV and Pisces V research submarines could soon be mothballed. Credit Kent Nishimura for The New York Times

    “It’s very unusual to have a facility that large and well-equipped in the middle of a large ocean basin,” said Robert Dunbar, a Stanford oceanographer. “They’ve done a remarkable thing over there, largely due to Terry’s expertise.”

    But today, Mr. Kerby faces the possible mothballing of his fleet. The forces at play are the same as in many other realms of science — dwindling budgets, of course. And robots.

    Robotic subs can stay down for days and reach extraordinary depths, instantly relaying their finds to scientists and an Internet-connected global audience. But they cannot go everywhere, and many scientists argue that studying the deep without direct human observation yields at best an incomplete understanding.

    “You can’t replace a Terry Kerby with a robot,” said Andy Bowen, principal engineer at Woods Hole. “It’s not possible.”

    At 65, Mr. Kerby is tanned and fit, thanks to daily two-mile ocean swims. He has been piloting submersibles at Makai for better than three decades, starting in the mid-1970s harvesting corals. He shifted to the University of Hawaii and the National Oceanic and Atmospheric Administration, which had bought the Makai facility to expand the nation’s deep-sea capabilities.

    In 1985, Mr. Kerby found the Pisces V submersible idled in Edinburgh and persuaded the university to spend $500,000 for it. Relatively big, it could dive to 6,500 feet. “She cost $4 million to build in 1972,” he said. “And would cost $50 million to build today.”

    Pisces V came with no instruction manual, but Mr. Kerby found it was highly maneuverable and could hover motionless, even in strong currents. It also operated untethered from a mother ship, allowing exploration of caves and overhangs. Coupling Pisces with the University of Hawaii’s research ship, the Ka`imikai-O-Kanaloa, and a home-built submersible platform enabled Mr. Kerby to carry out missions from 60 feet down, during surface conditions too rough for any other submersible.

    Temp 1

    Mr. Kerby racked up discoveries, beginning with exploration of the Loihi seamount off Kona.

    Lōʻihi Seamount

    Yellow iron oxide-covered lava rock on the flank of Lōʻihi

    Eighteen years of return missions have revealed that an area once thought dead is a vibrant world of myriad ecosystems and volcanism still shaping the Hawaiian Islands. Along Loihi and other slopes, the team discovered living corals that predate even California’s bristlecone pines.

    The Hawaii Undersea Research Laboratory (known as HURL) is based at the Makai pier on Oahu. Credit Kent Nishimura for The New York Times

    In 2000, Mr. Kerby acquired a sister sub, the Pisces IV, from Canada for $80,000. Exploring in tandem made diving safer and enabled film crews to show discoveries in the context of the submersibles. The subs have appeared in more than 20 documentaries, including National Geographic’s “Fires of Creation,” in which the oceanographer Robert Ballard, whose discoveries included the wreckage of the Titanic, descended with Mr. Kerby to the caldera of Loihi.

    Besides plumbing geological and ecological mysteries, the Pisces subs have made dives that sharpened views of history.

    A little more than an hour before the first bombs fell in Pearl Harbor on Dec. 7, 1941, the American destroyer U.S.S. Ward reported that it had sunk a tiny submarine near the harbor entrance. But in a blunder that still fuels conspiracy theories, the report never reached far enough up Navy command to initiate a mobilization of defenses. The Ward’s claim was disputed, even in the official Pearl Harbor investigation report. The sub thus became a holy grail for marine archaeologists and historians.

    In August 2002, Mr. Kerby lay across the bench of the Pisces V, 1,200 feet down, gazing at the dark, frigid world beyond his porthole. For hours he had been sweeping the seafloor four miles south of Pearl Harbor, hunting for the mythic sub amid three dozen potential sonar targets and fighting a rising sense of futility. “We were chasing our tails down there,” he said.

    But then, looming out of the darkness, Mr. Kerby faced a torpedo shape three times as long as the Pisces. It was a 78-foot-long submarine bearing the exact mortar damage – a four-inch hole punched just beneath its conning tower — described by the Ward’s crew.“We’d searched for 10mam years,” Mr. Kerby said. “I just couldn’t believe it.”

    After that find, NOAA directed Mr. Kerby to further document the wreck-strewn waters off south Oahu. In another National Geographic project, the team discovered four mammoth Japanese I-series submarines captured by the Navy at the end of World War II and scuttled to keep them out of Soviet hands.

    download mp4 here.
    The first view of a World War II-era Japanese I-400 submarine from the Pisces V submersible. Video by HURLSubOps

    Through these years, HURL operated Pisces on a budget of a few million dollars a year.

    Nestled among books, above, is the dive checklist for Pisces V. Credit Kent Nishimura for The New York Times

    “What the Pisces program has done, mostly underfunded and unappreciated, over the years is unmatched,” said Sylvia Earle, former chief science officer for NOAA. “It’s baffling to me that more understanding and funding hasn’t been heaped upon them.”

    Five years ago, piloted deep-sea exploration appeared on the verge of a boom, funded by wealthy explorer/entrepreneurs. In 2012, after spending $10 million building his Challenger Deep submersible, the filmmaker James Cameron became one of three humans to reach the 6.8-mile depths of the Marianas Trench, the deepest ocean spot on Earth — and the only one to do it solo. The Virgin Airlines founder Richard Branson promised a new era of exploration with his $17 million Virgin Oceanic submarine. And Eric E. Schmidt, Google’s chairman, joined with Dr. Earle on the $40 million Deep Ocean project.

    Yet all those programs have withered. And by fiscal year 2014, the deep-sea budget for NOAA was down to $26 million. For comparison, NASA’s exploration budget was $4 billion. The United States Navy has abandoned piloted submersibles with the exception of Alvin, which it owns jointly with Woods Hole. In 2013, NOAA said it would no longer fund the Pisces program, leaving the United States with no Pacific deep-sea facility. HURL has money to last until the beginning of 2016. After that, the university may be forced to sell the submersibles. “There are only eight deep-diving submarines left operating in the world” that can go 6,500 feet or deeper, said John Wiltshire, director of HURL and a member of the Woods Hole submersible scientific advisory committee. “So we’re about to lose a quarter of the world’s fleet.”

    What changed? To hear Dr. Ballard tell it, the shift began during a 1977 dive aboard Alvin off the Galápagos Islands. About 8,000 feet down, Dr. Ballard noticed a colleague paying more attention to the camera monitor than to Alvin’s tiny windows. “He turned his back on me to look at the screen,” Dr. Ballard said. “I said, ‘Why?’ He said, ‘I can get closer.’ I said, ‘Then why the hell are you here?’ ”

    Afterward, Dr. Ballard said he realized fundamental truths of piloted deep-sea exploration: It’s cold and scary, time in the deep is limited, and robotic vehicles might do the same work for less money. He persuaded the Navy to fund two remote exploration vehicles, Argo and Jason, for use by Woods Hole. On Sept. 1, 1985, Argo first filmed the wreckage of the Titanic. Since then, remote deep-sea vehicles have proliferated in exploration, mining and drilling. Dr. Wiltshire estimates perhaps 10,000 are in operation.

    NOAA’s deep-sea efforts are focused on two ships: its own Okeanos Explorer, based in Rhode Island, and the E/V Nautilus, a joint project with the Ocean Exploration Trust, founded by Dr. Ballard and based in Connecticut. Nautilus has an autonomous underwater vehicle that follows a programmed route and two tethered remote submersibles.

    Typically, Dr. Ballard’s ships carry just one or two senior oceanographers; engineers and technical staff deploy and monitor the submersibles, which, via satellite link, deliver real-time images across the world via the Internet.

    Terry Kerby and his Pisces subs have discovered more than 140 undersea wrecks and artifacts. Credit Kent Nishimura for The New York Times

    Dr. Ballard described a recent Nautilus expedition that sent its submersibles two and a half miles down into the Cayman Trough. In a piloted dive, the descent and ascent would take six hours each, leaving mere minutes for seafloor exploration. “Now we’re going down to 20,000 feet and spending days,” he said. “And we have the entire world participating.”

    To most marine scientists, including Mr. Kerby, robots have clearly won the deep-sea war. It’s now a question of whether lingering advantages to piloted exploration should be discarded. Mr. Kerby described a recent robotic mission that Pisces might have done better.

    In 2012, Ric Gillespie, a retired naval aviator, and Dr. Ballard announced a sonar hit off Nikumaroro Island in the South Pacific that might represent the wreckage of the Lockheed Electra flown by Amelia Earhart. Mr. Gillespie requested Mr. Kerby for the expedition, but the Pisces subs were down for maintenance, so his team instead relied on robotic technology. The tethered sub was unable to explore the near-vertical sea walls and could not deploy over days of rough seas. Eventually, an untethered robotic vehicle became lodged in a reef overhang and had to be rescued by a tethered robot. The recovery nearly required the University of Hawaii’s Ka`imikai-O-Kanaloa to deploy perilously close to a reef.

    “It’s a horrible way to search,” Mr. Gillespie said. “It’s like you’ve lost your car keys at night in your backyard and you’re looking for them through a toilet paper roll with a flashlight.”

    At the university, Dr. Wiltshire cited plans for bringing Alvin and the Nautilus rovers to explore newly created Pacific marine monuments. Rates for Nautilus are in the range of $35,000 to $40,000 a day, while Alvin and its support vessel Atlantis II cost $60,000 to $70,000 a day. HURL can deploy both Pisces subs for $48,000 a day, “and that’s not counting the transit time and expense to get there,” Dr. Wiltshire said. “It takes us 15 days, but it takes two months to bring those ships over from the East Coast.”

    Dr. Ballard countered that comparison must take into account the time his rovers can stay submerged — days at a time, as opposed to eight hours or so for Pisces or Alvin.

    Dr. Bowen, who oversees the robotic and piloted programs for Woods Hole, says piloted exploration still has plenty of benefit.

    Antiaircraft guns of an I-401 Japanese submarine, discovered by the Pisces submarines. Credit Hawaii Undersea Research Lab

    There’s no question that the strong suit for robotics is that you can engage a larger number of people in the process of exploration and discovery,” Dr. Bowen said. But taking in all the undersea factors — currents, sounds, land forms, interactions between animals and their environment — humans are still far better at synthesizing what’s going on in the deep sea, he said. “We hear that all the time from researchers who have looked at the video monitors and data screens from Jason, but then also gone down in Alvin. It’s stunning how different their perception of the environment is.”

    According to Craig McLean, the assistant administrator for oceanic and atmospheric research at NOAA, decisions about HURL’s future were mainly a matter of budget constraints and emerging technology. HURL was funded as part of NOAA’s National Undersea Research Program. Scientists competed for NOAA-backed studies, and the agency maintained and provided the equipment — like Pisces submarines — to the winners. That program was phased out in favor of an unpiloted, Internet-connected virtual model that includes on-call scientists around the world.

    “We realized we can’t afford to do it all,” he said. “So we had to ask, what are we doing and how can we have it be inclusive? So scientists who can’t dive — they have a presence through telepresence.”

    In addition to making headlines with discoveries of bizarre creatures, surveys with the Okeanos have, he said, had more practical applications. A fisheries survey, for example, resulted in the recent protection of 38,000 nautical square miles of ocean off the East Coast.

    Mr. McLean said that should a scientist bring a proposal before NOAA or the National Science Foundation that Pisces was well suited for, Mr. Kerby’s team could still get funding on a mission-by-mission basis.

    He further agreed with a sentiment expressed by Dr. Earle, that in a time of dramatic changes in the climate and ocean itself — some 90 percent of which remains completely unexplored — he would prefer that NOAA had a wider arsenal of discovery at its disposal. “We’re doing as much as we can,” he said. “But we have to get into these difficult situations where we have to make our priorities.”

    In the meantime, Mr. Kerby and his maintenance chief, Steve Price, have been hustling. Mr. Price has been funded to compile a database of all Pisces discoveries for use by NOAA. A World War II documentary project has kept Mr. Kerby busy lately, and a series of geology, undersea cable and sewer outfall surveys will keep HURL funded through year’s end. He says he is confident more work will materialize, preventing his crew from having to follow the route of many former colleagues into oil and gas exploration. He’d love to secure the resources not only to keep his subs running, but to add a full-time robot sub to HURL’s fleet.

    “An associate of mine at Woods Hole upper management said, ‘HURL doesn’t stand a chance,’ ” Mr. Kerby said. “ ‘They’re too far from the flagpole.’ Well, we are. We’re way out here on the ocean frontier, in the prime spots, and we’re one of the most cost-effective operations around. With all the new and unexplored monuments in the western Pacific, and all the groups that need to do that exploration, we’re the only viable tool with experience in these environments.”

    He paused.

    “We know what we can do.”

    See the full article here .

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