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 |
you like to contribute a story tip?
Get the URL of the story, and the related sf author, and add
Comment/Join discussion ( 0 )
Related News Stories -
Metalenses Now Reconfigurable With Liquid Crystal
'Hufhuf oil held in static tension...' - Frank Herbert, 1965.
NDB Nuclear Waste Battery Lasts A Lifetime
'Trillions of units of power could be compressed thus into an inch-square cube of what looked like blue-white ice.' - Edmond Hamilton, 1940.
Blaux Your Personal Commuter Cooling Unit
A cooling unit had to be strapped to every commuter's back, by law.
SunnyFive 'Window' Has Full Spectrum Angled Natural Light
'On the ceilings are screens.' - Stanislaw Lem, 1961.
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.
Salto Jumping Robot Now Sticks Landing!
'Lucky touched the leap knob and the hopper's leg retracted.'
Gyroscopic Median-Straddling Mass Transit Vehicles
'It was among these leviathans that the little gyrocar was daring to thrust its puny self...'
Bigrating Laser Beam-Riding Light Sail Is Self-Correcting
'That sail will be twenty thousand miles at the wide part.'
ISS Astronauts Test Estee Lauder 'Advanced Night Repair' Skin Serum
'Out in the New Moon, just ask for what you want...'
LG Wing Twisting Smartphone Might Be Fun
'A polycarbon screen unfurled...'
Mushroom Coffin Returns You To Nature, Naturally
'She touched the leaf. She was wanted.'
Will ATT Offer Ad-Subsidized Cellphone Service
'For long-distance calls the ratio of commercial to conversation was as high as 10 to 1...'
Gyro-X Self-Balancing Two-Wheeler Car
'Indeed, the gyrocar was a sight to make a man look twice.'
Beat Covid-19 With AIR By MicroClimate - At Last I Get My PAPR
More than just a bubble.
Mi TV LUX Transparent Edition OLED TV
The Look of Things To Come.
Metalenses Now Reconfigurable With Liquid Crystal
'Hufhuf oil held in static tension...'
'Alexa For Residential' A Landlord's Dream (Tenant's Nightmare?)
'...unseen mechanical entities... that are in our very midst. One of them following each of us.'
Gather Ye Moonrocks While Ye May
'The law of filing on newly discovered asteroids was definite.'
InMotion V11 Electric Unicycle Gets Air (Video)
'A tumblebug does not give a man dignity...'
Rid Thyself Of Ads On The Newsbox
'Can't we scramble that commercial?'
A.I. Jesus Proclaims Machine Gospel
'... he crossed the waiting room to the Padre booth; inside he put a dime into the slot and dialed at random.'
More SF in the News Stories
More Beyond Technovelgy science news stories