NASA builds a nose for bad news
- By Paula Shaki Trimble
- Jun 26, 2000
While space shuttle astronauts are busy tending to their duties and scientific
experiments, NASA can smell trouble 250 miles away.
An electronic nose that uses computers and specialized sensing film
to work much like a human nose is being tested by researchers at NASA's
Jet Propulsion Laboratory as a way to detect unsafe chemical levels on the
International Space Station.
After a space shuttle flight in October 1999 successfully demonstrated
the technology, called E-Nose, researchers at JPL and the California Institute
of Technology began working to expand its sensitivity and shrink its size.
Amy Ryan, principal investigator for E-Nose at JPL, said the instrument
could be an event monitor on the International Space Station to alert the
crew if there is a spill or leak. "There's a lot of room on the space station,"
Ryan said. "The more automated you can make this kind of thing, the better
off the crew is."
Ultimately, E-Nose will identify an unsafe element in the air and send
a signal to the space station's environmental control system, and a central
computer will decide how to react, she said.
Nathan Lewis, a professor at Caltech, designed the E-Nose sensing films,
and NASA designed the instrument's hardware and associated processing software.
NASA adopted a commercially available Hewlett-Packard Co. handheld for E-Nose.
The instrument also has a sampling chamber and air filters, and NASA designed
the data acquisition system and wrote data analysis software.
NASA has been developing E-Nose for about four years, but the concept
of an electronic nose has been around for about 20 years, Ryan said. It
has taken off in the commercial market as well, with Cyrano Sciences Inc.
offering Cyranose 320, a product built around the Caltech sensing films,
primarily to the food and petrochemical industries.
Scientists at JPL are beginning to talk to other NASA departments and
other agencies about new applications for E-Nose, Ryan said. The Environmental
Protection Agency and defense agencies would be prime candidates, she said.
E-Nose has been identified as a possible environmental monitor in aircraft
cabins and on submarines, as well as in the oil, gas and food industries.
The size will be easy to condense, Ryan said. The E-Nose NASA used on the
shuttle is the size of a large paperback book and weighs about 3 pounds.
Ultimately, it could be the size of a tennis ball, she said.
Much like the human nose, E-Nose's sensors identify smell based on patterns
that it already recognizes. "Part of the power is the ability to train it,"
The E-Nose software has been trained to recognize 12 scents, and scientists
are planning to train it to identify 20 to 30 common contaminants. It is
also trained to detect contaminants based on the maximum level to which
astronauts can be exposed for one hour. Ryan said she hopes to expand that
capability to the maximum level of exposure for 24 hours. For example, astronauts
can be exposed to 30 parts per million molecules of ammonia for one hour
but 20 parts per million of ammonia for 24 hours.
"What we envision...is several [units] distributed on the space station
connected to a central computer, which will take the data and control the
environmental controls," Ryan said.
Cyrano, meanwhile, has not begun to pursue applications outside the
food and beverage and petro- chemical industries, but Rick Sill, Cyrano's
vice president of sales and marketing, said he envisions markets in government
agencies and private industry for detection of narcotics, explosives and
The Cyranose product is a handheld and sells for about $8,000. Cyrano
is also working with Welch Allyn Inc., a medical instrumentation firm, to
develop sensing technology that could detect cancers and ulcers based on
changes in the makeup of breath.