Robots in Antarctica
Use of autonomous vehicles grows as technology improves and science needs increase
Posted May 15, 2009
Antarctica is more accessible than ever before to scientists studying its climate, ecosystems and glaciological processes. But there are still places too dangerous, too remote or simply too expensive to send people and standard equipment to conduct polar research.
Instead, robots are carrying out some of the scientific work today, from diving under ice shelves to flying low over vast ice sheets to mapping the hidden realms below ice-covered lakes and seas.
These aren’t necessarily the robots of popular science fiction that accompanied Buck Rogers into space, but instead are unmanned airplanes capable of flying pre-programmed routes or automated submarines that venture far below ice shelves where people can’t go.
“We want people to focus on the best science, and we see these things as potentially good tools,” said Antarctic Sciences Division Director Scott Borg in the NSF’s Office of Polar Programs.
Only 20 years ago, there were relatively few sophisticated instruments, robotic or not, on the continent, according to Borg. To keep an automated weather station operational in the polar winter was a minor miracle. Now there are scores of continuously operating observatories, collecting not only weather data but also information on the flow rates of glaciers and the vertical rebound of bedrock as the ice sheets shed weight while they drain into the ocean.
Power systems improved. And real-time communication and data transfer via Iridium satellites meant scientists no longer have to revisit every instrument strewn across a continent as large as the United States and Mexico combined.
“The robots that you’ve seen are kind of an extension of that [innovation],” Borg said. “NSF as a whole has been encouraging the development of these technologies.”
Pre-fab versus built from scratch
Sometimes these instruments are simply existing technologies that polar scientists bring to the Ice because they are the best tools for the job.
For example, a small, unmanned aerial vehicle (UAV) used for studying hurricanes and other weather phenomena will fly out of McMurdo Station this year for research on the atmospheric conditions surrounding polynyas, areas of open water surrounded by sea ice.
“We’re using their technology to make measurements in an equally harsh environment in the Antarctic, a place we wouldn’t be able to fly otherwise,” said John Cassano, principal investigator on the project with the University of Colorado in Boulder. “It’s been used in [the arctic] before, but the Aerosonde has never been used in Antarctica before.”
The UAVs fly a pre-programmed route using GPS waypoints, though a pilot can alter the flight plan at any time. The instruments aboard the plane, with a wingspan of about three meters, measures conditions like wind speed and temperature, but the aircraft also carries a camera, a laser altimeter and an infrared thermometer, depending on the mission.
Interestingly, the high-tech robot has a very low-tech method for takeoffs and landings. “The AUVs get launched off the top of a pickup truck,” Cassano said. The ground crew sets the plane in a rack on top of the truck, and then drives across a flattened ice runway at about 60 mph to get the Aerosonde MK4.4 into the air.
On its return to the airfield, the plane slides to a stop on its belly. “It’s a smooth surface. We don’t have any sastrugi, any drifts of snow,” Cassano noted. “When they touch down on the ground, we’re pretty confident it will be a smooth landing.”
On the other end of the spectrum is the Meridian, a much larger UAV developed specifically for polar research by engineers at the Center for Remote Sensing of Ice Sheets (CReSIS), a National Science Foundation-funded Science and Technology Center at the University of Kansas in Lawrence. There were simply no automated airborne platforms capable of flying the missions scientists envision for the detailed measurements they need of ice sheets.
“It’s a complex thing to design an entire aircraft. It would have been ideal if we could have found an aircraft that could satisfy this mission but that wasn’t the case when we started designing this,” said Richard Hale, an associate professor at the University of Kansas, who is leading the team developing the new aircraft.
At more than half a ton in weight and with a wingspan of eight meters, the Meridian will be the first heavy fuel engine UAV to fly in Antarctica when Hale and his crew test its capabilities this coming field season. Most UAVs carry about 2 kilograms of equipment, Hale said. The Meridian can lug 60 kilograms with a range of about 1,600 kilometers.
“This is a science platform that’s readily adaptable to current state-of-the-art instrumentation needs,” Hale said.
Those instruments are growing ever smaller as engineers work to miniaturize sensors and other tools to satisfy an array of science missions. But miniaturization is not just about outfitting robots with more tools than a Swiss army knife.
Take the ENDURANCE robot, a nearly Volkswagen-sized instrument funded by NASA and supported by the NSF for a project in the McMurdo Dry Valleys, a relatively ice-free area in Antarctic used for ecosystem studies. The region is also a useful analogue for the sort of extreme environments found on other planets and moons, hence NASA’s interest.
Scientists used the autonomous underwater vehicle (AUV) last year to explore an ice-covered lake — an environment that might exist on Jupiter’s moon Europa. ENDURANCE may one day journey across the stars on a mission to discover life on that cold moon. But it will have to lose a lot of weight.
“It’s not something that could easily be put into a rocket,” Borg noted. Shrinking the scientific platform as well as the instruments will be a key to further exploration in Antarctica and beyond, he said.
Peter Doran, principal investigator for the ENDURANCE project as well as for a long-term ecological study in the Dry Valleys, said money is the main obstacle to miniaturization.
“How long [for deployment] is on the scale of a few years,” said Doran, with the University of Illinois at Chicago. “If there is a mision, and sufficient funding, there are no major impediments to scaling things down.”
Noted Borg, “One day we might be able to put a robot with those kinds of sensors on it down a borehole and into a subglacial lake. NASA has strong interest in miniaturizing things as well. Integrating instruments into a coherent system that works well is a major challenge.”
A biologist interested in the marine critters that dwell on the seafloor in Antarctica has put together a team to develop a remotely operated vehicle (ROV) just skinny, rugged and light enough to take that plunge down the proverbial rabbit hole in the near future.
An adjunct professor in benthic ecology at Moss Landing Marine Labs in California, Stacy Kim and her team have spent the last two field seasons putting SCINI (Submersible Capable of under Ice Navigation and Imaging) through its paces to perfect its capabilities for a variety of future science missions.
Shaped like a torpedo and boasting a waistline of only 15 centimeters, SCINI is easy to transport and handle. It can currently cruise to depths of 300 meters, and an expected upgrade to its camera housing should significantly boost its diving limit to more than 1,000 meters. (In comparison, human divers in Antarctica are allowed to dive to 40 meters, which is the standard recreational limit.)
This year, Kim and her team, which includes engineer Bob Zook, hope to challenge SCINI with dives under a permanent ice shelf. Just below the shelf is a thick soup of ice called frazil ice. If SCINI can muscle its way through the needle-like ice crystals without problems, it will be ready for a variety of complex science missions.
“One of the places that have been relatively unexplored in Antarctica is underneath these permanent ice shelves,” Kim said. “If we can prove that SCINI can access this system and work productively in them, then it opens it up for anybody — whether it’s a benthic ecologist or a glaciologist or a water column chemist. Whatever their interests are they can utilize SCINI as a tool.”
At play in the field
Ayanna Howard used to develop robots for jobs outside planet Earth when she worked for NASA’s Jet Propulsion Laboratory. Now, as an associate professor of Electrical and Computer Engineering at Georgia Institute of Technology, she has turned her attention to developing intelligent rovers for missions closer to home.
“I’ve always been interested in using robotics for science. That’s always been a passion,” said Howard. That passion may someday send some of her latest creations, what she calls SnoMotes, to Antarctica.
In collaboration with scientists from Pennsylvania State University, Howard and her lab, which specializes in robotic artificial intelligence, took an off-the-shelf toy, a snowmobile, and modified it for complex navigation and reasoning. Their eventual goal is to outfit the robots with sensors that would take measurements of ice sheets that scientists can use to create more accurate models of ice sheet dynamics.
The SnoMotes are autonomous robots and are not remote-controlled. They use cameras and sensors to navigate their environment, working together in a team — in what Howard calls a “sensor network” — to cover an area in a methodical grid pattern.
The robots have to figure the best way to carry out the science mission based on their position and the conditions on the ground. “That’s where the autonomy comes in,” Howard said.
The SnoMotes will head to Alaska this summer for field tests, though Howard said it will be at least a couple of more years before the ski-equipped bots are ready for the tougher Antarctic climate. “We’re going to have to beef up a couple of things. One is the power requirement.”
Scientists on the polar plateau, living and working at an altitude of more than 3,000 meters for months at a time this past field season, found some instruments just aren’t ready for the Antarctic.
A small UAV developed by engineers from Norway, and successfully used in other colder climes, didn’t do well in the frigid, thin air. It managed only a couple of short flights during the nearly four-month, overland traverse conducted by Norwegian and U.S. scientists across East Antarctica.
“It wasn’t the scientific tool that we had hoped it would be,” said Ted Scambos, lead scientist at the Boulder, Colo.-based National Snow and Ice Data Center who accompanied the expedition this past season. “The plateau is just more of a challenge than just about anywhere else on Earth.”
Despite the occasional setback, robots are already exploring Antarctic frontiers where humans can’t go.
A robotic submarine made only the second foray ever underneath an ice shelf this past field season, traveling 60 kilometers under the ice. The Autosub 3 that scientists deployed on the two-month science cruise to Pine Island Bay was developed as part of a five-year research program, Autosub Under Ice, supported by the British National Environment Research Council.
“The sub was basically in the same configuration as it had been during that program, although work had been done following that program to make the operational systems more robust,” said Adrian Jenkins, a scientist with the British Antarctic Survey (BAS) who was a co-principal investigator on the Pine Island cruise. Jenkins credits those modifications for helping the yellow submarine survive an impact with the ice during one of its six missions.
While the AUI program adapted existing technology for under-ice exploration, researchers had always intended to use the autosub in polar environments, particularly for exploration below the ice, according to Jenkins. “So the non-ice-capable vehicles were always seen as a stepping stone towards the ultimate goal,” he said.
Implementing effective sonar systems to identify under-ice hazards — and developing the software to help the sub decide on how to maneuver around obstacles — was a major challenge, according to Gwyn Griffiths, who heads the project lab.
“Effective collision avoidance has been key for work under sea ice and under shelf ice, where the seabed topography and the ice canopy topography are unknown, and where objects such as grounded icebergs can pose hazards to the progress of the vehicle,” he said.
There may be manned subs capable of extreme depths, but Jenkins said he believes there are few if any able to operate below the ice.
“It is also a very risky environment, with no chance whatsoever of surfacing in an emergency,” Jenkins said. “Therefore, I think that beneath ice shelves is one place manned vehicles will never go. So, this is one example of where AUVs are not replacing people, but undertaking work that could otherwise not be done at all.”
However, in the future, will robots do fieldwork currently performed by people on ships, in the air or on the ground?
Borg said he believes the U.S. Antarctic Program is a “long way from replacing people with robots.” In the long term, with continued miniaturization of components and the development of ever more sophisticated navigation systems, we should expect to see more unmanned planes in the Antarctic skies, he predicted.
“That’s going to be further down the line, but eventually we’ll get there,” he said, “but I think there’s almost always going to be a continuing need for aircraft systems with manned aircraft to do development work of new sensors.”
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