From...
Mt. Everest challenges technology, climbers alike
May 21, 1998
Web posted at 2:10 PM EDT
by Rebecca Sykes
(IDG)
-- A climb up the world's highest mountain is no afternoon stroll, and
the technology supporting this month's 1998 American Everest Expedition
is not your average office equipment.
Armed with equipment specially designed by the Media Lab at the MIT,
the expedition's professional mountaineering team will be seeking data
about Everest's climate and geology. They will also serve as human guinea
pigs for a study of human physiological response to a place at the limits
of human ability to survive.
"Instead of guiding up other people, they are climbing for science,"
said Michael Hawley, the MIT professor who headed up the Media Lab's
technology effort. "This year, there's going to be a tremendous gush
of data coming off the mountain."
That gush of data has been part of the technological challenge during
the preparation for this climb to the 29,028-foot summit of Everest.
The scientists behind the expedition have had to wrestle with the design
and operation of the computer equipment that the climbers will carry
with them, tackling issues from power conservation and its corollary,
battery life, to real-time monitoring of remote systems.
Technology bound for Everest cannot be complex to operate, because
its climber users will likely be physically clumsy and mentally dulled
from oxygen deprivation and fatigue. Nor can it be finicky, because
the climate stresses the technology just as surely as it squeezes the
humans. Above 26,000 feet, there is one-third the oxygen present at
sea level, and temperatures on the mountain can fluctuate wildly, from
well below zero Fahrenheit to uncomfortably hot on cloudless days when
the sun reflects off the snow.
"The problem is you've got to build something that's absolutely bombproof,"
Hawley said, if it is to withstand the climatic conditions, and "idiotproof"
to withstand rough handling by the climbers.
Media Lab scientists and students have designed special extreme-climate
weather sensors and vital-sign monitors so that researchers at the Yale
School of Medicine and Boston's Museum of Science can conduct their
experiments on Everest, whose summit literally pokes into the jet stream.
The experiments will take place this month during the short window when
conditions relent enough to make climbing big mountains such as Everest
possible.
Even at base camp, more than 10,000 feet below the summit, the technology
must be rugged. The computers that will process the data coming off
the mountain must be able to function in a tent at 17,500 feet -- higher,
that is, than the Alps or the Rockies, and a far cry from the climate-controlled
office most computers call home.
Still, things are tougher for the climbers themselves. Those who miscalculate
and are high on Everest when the weather turns bad usually don't make
it back down. In 1996, the most lethal year on the mountain, one person
died for every six-and-a-half who reached the summit. Even in the least
deadly year, 1993, the perils of exposure, avalanches and falls are
such that one person died for every 16 who made it to the top.
To monitor those perilous weather conditions, which have been only
spottily recorded, researchers want to install a sensor at the summit.
Hawley and his team created a probe designed to measure the harsh climate
without succumbing to it.
"Turns out that no one has measured the wind speed at the summit,"
and only a few measurements of barometric pressure or temperature have
been taken, Hawley said. Moreover, measurements taken by previous climbers
have recorded conditions that were by definition atypical, because climbers
make a summit attempt only on "good" days, he said.
To help researchers gather weather data, the Media Lab team built
a 5-pound cylinder that will be bolted onto an existing pole steps from
the summit. The cylinder, roughly the size of a human thigh, is mostly
batteries, with a coin-size sensor to measure wind speed, temperature,
barometric pressure, light and humidity, according to Hawley. If it
is installed and working properly, it will record and transmit data
back to the Media Lab by tossing bits up to a passing satellite 36 times
a day for one year, he said.
Researchers also hope to obtain precise measurements of the summit
using geo-positioning satellites. Even though ice, rocks and snow routinely
slough off the mountain, Everest is getting higher, thrust upward from
the same collision of the Indian plate with the Eurasian plate that
created the Himalayas some 50 million years ago.
As the climbers make their way to the summit, they will be wearing
backpacks designed at the Media Lab for Yale researchers conducting
experiments on human functioning under extreme conditions. Yale is pursuing
its "extreme" research in partnership with the National Aeronautics
and Space Administration, with an eye toward the coming human exploration
of "the hostile and remote environment of space," said Ronald Merrell,
chairman of the Yale medical school's department of surgery.
Everest is certainly hostile and remote, and given the extreme conditions,
Yale researchers want to track climbers' skin temperature, heart rate,
blood oxygen level and body-core temperature. In response, the Media
Lab team devised a sensor system that was lightweight, because the gear
and oxygen most climbers carry are already a heavy burden.
The sensors also had to function for prolonged periods without requiring
fussy maintenance such as battery changes. Media Lab graduate student
Robert Poor had previously created vital-sign monitors for marathon
runners, but a summit attempt on Everest can take up to a week, far
longer than the several hours it takes runners to complete a marathon.
"It's a really difficult problem to get bits associated with your
person tied back in to networks," even under the best of circumstances,
Poor said. "Logging a week's worth of data and beaming it wireless down
the mountainside is a substantial challenge."
The Media Lab team designed packs that will lie snug against the male
climbers' chests for the duration of the summit attempt. The packs weigh
around 2 pounds apiece, and each uses three commercially available 9V
lithium batteries. In part because they will be pressed against climbers'
warm bodies, researchers made no modifications to the nonrechargeable
batteries, according to Poor. "If anything makes me feel guilty about
this project, it's that we'll be disposing of a lot of batteries," he
said.
Obtaining power without bulk was probably the biggest obstacle. The
pack batteries had to be long-lasting without being too heavy or numerous,
Poor said, "so that people wearing these things aren't just carrying
around a battery pack with a little technology on the side."
The Media Lab solved the power problem by creating sensors that use
energy intermittently. The batteries are in "sleep" mode for five minutes
at a stretch, drawing minimal power, and awaken every sixth minute to
provide the power that the sensors need to take their readings, fire
up their radio transmitter and send the data back to base camp.
"What we've done right there is reduce the number of batteries we
need by a factor of six," Poor said.
Disk drives, too, needed special attention for the conditions at base
camp, because they operate using a bubble of air and air density fluctuates,
depending on altitude. Drives are manufactured according to specifications
for different altitudes, but so far there has not been much demand for
machines that can function well at 17,500 feet, according to Ted Selker,
IBM fellow at the Alamaden Research Center in San Jose, Calif.
Selker accepted the design challenge by making a 4-pound ThinkPad
560 work at high altitude and low temperatures. Testing showed that
their drives appear to function as requested, with the bonus finding
that they are now rated to function at 20,000 feet.
With the equipment ready to go, the main task during the expedition
is the monitoring of the systems. At the request of the Yale researchers,
the Media Lab designed the systems so that their sleep cycle can be
overridden in the event of suspicious-looking data. The override feature
also lets them immediately initiate a second reading of a measurement.
Signals that a climber is spiraling toward physiological trouble can
be double-checked immediately, instead of waiting for the next cycle
of readings, according to Merrell.
Reaction must be immediate if a sensor detects a drop in core temperature.
"Somebody needs to tell the climber, 'your core temperature is down,
you're in trouble'," Merrell said. "Waiting five minutes for confirmation
may be an extraordinary amount of time in terms of physiology."
Although Yale scientists can radio the climbers with the results,
both groups need to appreciate that some of the technology naturally
will fail during these field tests, Poor said. "We wanted to make sure
they understand that this is an experimental system," he said. "We're
not assuming that this is data that the climbers will use to make mission-critical
decisions."
Nonetheless, medical ethics require that scientists at base camp let
climbers know if readings look dangerous, according to Merrell. "It
really was not reasonable to test out these things passively," he said.
"If you're field-testing something that says your subject is in grave
physical danger ... you must tell the subject."
The Yale researchers at base camp have established a telemedicine
link to medical databases for information they can relay to the climbers
in an emergency. However, rescue still will be unlikely from a place
where the thin air that robs mountaineers of strength and judgment also
prevents helicopters from flying in for evacuation. The improbability
of rescue is a harsh fact known to all who climb big mountains, and
monitoring climbers' vital signs from base camp won't much change the
outcome of any emergency.
"It's a play that will unfold," Poor said.