Caltech Electronic Nose: The Lewis Group Smells Success

The Lewis Group, at Caltech, has worked out a unique approach to the idea of an electronic nose. They use arrays of simple, readily fabricated, chemically sensitive conducting polymer films.


(Response patterns for three different solvents
on a 17 element sensor array.
)

When a polymer film is exposed to a vapor, some of the vapor partitions into the film, causing it to swell. The electronic nose detects this as an increase in the electrical resistance of the film, a value that can be quantified for each film.


(20 detector array creates pattern identifying
the vapor and concentration
)

An array of sensors that respond individually to vapors can produce a unique pattern for a given vapor mixture. Pattern recognition done on the output signals from the electronic nose can classify, identify and even quantify, the odor being investigated. The researchers claim that this response is very similar to the way that our own olfactory sense produces diagnostic patters and then sends them to the brain.

The Caltech nose has been demonstrated to detect odors in an ordinary room background; it can direct robotics to turn toward the source of the odor. Signals can be read in real-time or near real-time, because the swelling of the polymer begins immediately after exposure to the vapor.

Even better, the Caltech nose can be used over and over (just like your nose). The films return to their initial, unswollen state after the vapor source is removed; this reversibility has been demonstrated for tens of thousands of exposures.

My first exposure to the electronic nose idea was, of course, the mechanical hound of Ray Bradbury's classic Fahrenheit 451 The mechanical hound could also turn and move in the direction of an odor - very quickly, it turns out, and in real-time.

The mechanical Hound slept but did not sleep, lived but did not live in its gently humming, gently vibrating, softly illuminated kennel back in a dark corner of the fire house...

Nights when things got dull, which was every night, the men slid down the brass poles, and set the ticking combinations of the olfactory system of the hound and let loose rats in the fire house areaway. Three seconds later the game was done, the rat caught half across the areaway, gripped in gentle paws while a four-inch hollow steel needle plunged down from the proboscis of the hound...
(Read more about Bradbury's mechanical hound)

Use these links to get a snootful of additional olfactory electronics:

Read more details at the Lewis Group Electronic Nose research page; via PhysOrg.

Scroll down for more stories in the same category. (Story submitted 10/24/2007)

Follow this kind of news @Technovelgy.

| Email | RSS | Blog It | Stumble | del.icio.us | Digg | Reddit |

Would you like to contribute a story tip? It's easy:
Get the URL of the story, and the related sf author, and add it here.

Comment/Join discussion ( 0 )

Related News Stories - (" Engineering ")

Stick-On Tape Speakers, As Predicted By Bruce Sterling
Flexible tape speakers, someday.

Has Climate Change Already Been Solved By Aliens?
'I had explained," said Nessus, "that our civilisation was dying in its own waste heat.' - Larry Niven, 1970.

Skin Electronics 3D Printed
'June's body is a tracery of lambent lines, like some arcane capillary circuitry...' - Paul Di Filippo, 1985

Super-Resolution Microscopy Provides '4D' Views
View the magnified interior of living cells.

 

Google
  Web TechNovelgy.com   

Technovelgy (that's tech-novel-gee!) is devoted to the creative science inventions and ideas of sf authors. Look for the Invention Category that interests you, the Glossary, the Invention Timeline, or see what's New.

 

 

 

 

 

Current News

LA Subway Scanner, As Seen In 'Total Recall'
'I'm afraid to tell you this Mr. Quaid, but you have suffered a schizoed embolism...'

Sion Electric Car Covered With Solar Panels
'It drew its power from six square yards of sunpower screens on its low curved roof.'

PAL-V Liberty Flying Helicopter Car
'...lifted themselves to skimming flight upon whirling helicopters."

Space Drones - UK's Effective Space To Launch Rocket Tugs
'Twenty rocket tugs towed it from its Earth hangar out into space.'

DIY Autonomous Robot Detects Trash
'The search-bug detached itself and rolled forward.'

Ancient Russian Walking Excavator Would Be Perfect RV
I don't need it to go fast, it just needs to amble along.

ELROI Satellite 'License Plate'
Robert Heinlein was thinking about this in 1941.

When Robots Beg For Their Lives
"Just what do you think you're doing... Dave.'

Do You Still Want A Folding Screen Phone?
'A paper thin polycarbon screen unfurled...'

'Snapchat Dysmorphia' Now A Thing, Say Plastic Surgeons
'The program raced up the screen one scan line at a time, subtly smoothing, deleting and coloring.'

Quiet Electric Cars Law Finalized By US Transportation Department
'... a sound tape to supply the noise'

Drone Assassin Fails To Kill Venezuelan President
'The spotter descends, and we think it searches the vicinity, looking for the victim's face...'

Stick-On Tape Speakers, As Predicted By Bruce Sterling
Flexible tape speakers, someday.

Bezos Invites You To New Life In Off-World Colonies
'A new life awaits you!'

Amazon's Rekognition System Sees Criminals In Congress
'... the imprint of her image on the telephoto cell.'

Build Your Own Space Suit For Cheap
'I'm going to pump the air from this room... so that the interior will be like airless and pressure-less space.'

More SF in the News Stories

More Beyond Technovelgy science news stories

Home | Glossary | Invention Timeline | Category | New | Contact Us | FAQ | Advertise |
Technovelgy.com - where science meets fiction™

Copyright© Technovelgy LLC; all rights reserved.