WASHINGTON, May 31 /PRNewswire-USNewswire/ -- In late May, a
NASA-funded robot successfully navigated one of the world's deepest
sinkholes. The mission could be a prelude to a future mission to Jupiter's
moon Europa, believed to contain a liquid water ocean. The Deep Phreatic
Thermal Explorer (DEPTHX) is a 3,300-pound, computerized, underwater
vehicle that makes its own decisions. With more than 100 sensors, 36
onboard computers, and 16 thrusters and actuators, it decides where to
swim, which samples to collect and how to get home.
DEPTHX dove repeatedly into the depths of Mexico's mysterious Sistema
Zacaton sinkhole, or cenote, testing a variety of sensors, sonars, and
other equipment. The robot also obtained numerous samples of water and the
gooey biofilm that coated the cenote walls. Reaching depths of 1099 feet,
the battery-powered robot traveled deeper into the sinkhole than human
divers could reach. Though initially operated on a data-tether, DEPTHX also
operated autonomously, without a tether or human guidance, for up to eight
hours at a time.
On May 26, DEPTHX autonomously descended into Zacaton, collected a wall
core sample and safely returned to the surface, all without scripted
instructions. Two days later, again operating without a tether, DEPTHX
further explored and mapped Zacaton, using a novel form of
three-dimensional navigation known as Simultaneous Localization and
Mapping.
Both of these capabilities -- autonomous science operations and
autonomous navigation and mapping -- will be useful to a new generation of
planetary robotic systems.
Funded by NASA's Astrobiology Science and Technology for Exploring
Planets program and led by principal investigator Bill Stone of Stone
Aerospace, Inc., Austin, Texas, the project now is ready to take the next
step in Earth exploration.
"The successful tests in Mexico pave the way for a trip to Antarctica's
Lake Bonney in late 2008. There, conditions more closely resemble those on
Europa," said John Rummel, senior scientist for astrobiology at NASA
Headquarters, Washington. "We're learning how to explore Europa by first
exploring analogue environments here on Earth."
Although NASA's long-term goal is to build a smaller robot that can
function independently on another world, DEPTHX is generating important new
discoveries. For the first time, scientists can collect specimens from the
undisturbed world of sinkholes or other deep watery environments, bringing
back new types of bacteria that one day may lead to earthly benefits such
as advanced medical therapies or new kinds of materials.
While DEPTHX engineers aimed to build a machine that behaves like a
microbiologist, smaller versions of the robot also might be equipped as
safety inspectors to examine underwater dams or drilling platforms.
The robot explored the underwater environment and navigated back to the
surface at the end of each day using 500 three-dimensional maps continually
updated in real time on supercomputers built by scientists at Carnegie
Mellon University, Pittsburgh.
DEPTHX is a $5 million, three-year project that includes scientists and
engineers from Stone Aerospace; Carnegie Mellon University; the University
of Texas at Austin; the Colorado School of Mines, Golden; the University or
Arizona, Tucson; and the Southwest Research Institute, San Antonio, Texas.
To learn more about the DEPTHX and other NASA projects, visit:
http://www.nasa.gov.
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