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Cell Phones Could Sniff Out Deadly Chemicals
Hugh Pickens writes "Science Daily reports that Homeland Security's Science and Technology Directorate's Cell-All is an initiative to equip cell phones with a sensor capable of detecting deadly chemicals. A chip costing less than a dollar would be embedded in cell phones and programmed to alert either the cell phone carrier to the presence of toxic chemicals in the air, and/or a central station that can monitor how many alerts in an area are being received. While one alert might be a false positive, hundreds would indicate the need for evacuation. 'Our goal is to create a lightweight, cost-effective, power-efficient solution,' says Stephen Dennis, Cell-All's program manager. Does this always-on surveillance mean that the govenment can track your precise whereabouts whenever it wants? On the contrary, DHS says; Cell-All will operate only on an opt-in basis and will transmit data anonymously."
Now I have to turn off my cellphone when I cook meth.
You can't take the sky from me.
One might be a false positive. Hundreds might indicate the need for evacuation.
So how is that person holding the false positive going to react? Maybe they're the first phone to realize it? Maybe they don't understand what 'false positive' means?
For personal safety issues such as a chlorine gas leak, a warning is sounded; the user can choose a vibration, noise, text message or phone call.
I'd be concerned those false positives might not be warmly received. Especially if someone in a crowded Starbucks has a phone that starts to alarm and says "Oh my god, there's chlorine gas in here!" You might be hit with some lawsuits after a few people are injured in a stampede. Contrived scenario? Maybe. But people are less than rational beings when their lives are perceived to be at stake. While academia is right on board some of the larger cities have been a little resistant toward citizen operated detectors.
My work here is dung.
A chip costing less than a dollar is embedded in a cell phone and programmed to either alert the cell phone carrier to the presence of toxic chemicals in the air ...
Well look on the bright side, the Chinese worker who makes the chip only has to step outside of the factory and turn it on to see if it works on a wide spectrum. Of course who would be foolish enough to risk their job, life, liberty and pursuit of happiness with a complaint about a local government official being bribed into letting your employer pollute to its heart's content?
My work here is dung.
DHS says Cell-All will operate only on an opt-in basis and will transmit data anonymously.
Right, because the DHS has such a fine track record of opt-in, anonymous data, and not using it for other purposes. While they might have opt-in it will be buried under pages of the cellphone contract or settings and will be on by default requiring the user to spend a few hours figuring out where it is hidden to turn it off. Anonymous transmission, maybe anonymous by the fact it relays cell tower coordinates with an identifier number through which they can gain the personal information "only" by asking the cell provider.
My question is, how often are dangerous chemicals released in the air for this to be needed? Places which handle dangerous chemicals already have detection systems in place, it's not often you hear of a city being evacuated because of some sort of toxic accident. Or is it to help combat terrorism? It sounds to me like it's a location based detection system which will be [ab]used to detect drugs and other activities instead of to "protect the public".
Orwell was an optimist.
Also known as cocaine. Or tetrahydrocannabinol, diacetylmorphine, methamphetamine or similar killers of children. What, don't you want your cellphone to be used to sniff out the murderers of children? What kind of monster are you?
If you were blocking sigs, you wouldn't have to read this.
Awesome now another chip in my phone to help trim away my already bad phone battery life!
Most broad spectrum gas detection sensors generally work by heating up a strange oxide catalyst and measuring a resistance change. Not entirely unlike an O2 sensor in a car exhaust system.
You can buy a gas sensor off the shelf from boutique online stores for about $5 each, so $1 in bulk wholesale is believable, or at least possible.
The problem is power consumption. Check out a MQ-4, at a whopping 750 mW heater power. Thats probably more than the entire rest of the phone at peak. And the heater has to preheat for a minimum of 24 hours to provide good data, this is not something that "goes to sleep mode". Thats 3/4 of a watt, all day, every day. It will literally make a poor hand warmer in ones pocket.
http://www.sparkfun.com/commerce/product_info.php?products_id=9404
http://www.sparkfun.com/datasheets/Sensors/Biometric/MQ-4.pdf
The parts in the sensor are not cheap. The manufacturer is already highly motivated to make it as small and light as possible, which would incidentally make it low powered. At this time, thats the best "we" can do with current technology. Its not like I cherry picked the highest power unit available. However, higher power would imply bigger would imply more durable, so I'd think a cell phone model might actually be worse.
My very-much-non-smartphone uses a 3.7V lithium battery and runs "several days" between charges. Lets claim 4 days. So, 5 volts / 33 ohms = 150 ma times 5/3.7 (voltage upconverter) means 200 ma continuous draw from my 3.7V battery. 200 ma times 24 hours/day times 4 days, equals about 19 AMP-HOURS just to run the gas sensor. We'll add another amp-hour to run the phone itself, and round up to 20 AH.
Batteryspace sells a nice 20 AH lead acid battery... 14 pounds, 7 inches by 3 inches by 7 inches. Rechargeable lithium, maybe half that size and weight. We are looking at the revival of the "bag phone" circa 1980s.
http://www.batteryspace.com/sealedleadacidbattery12v20ah240whs.aspx
I would qualify this idea as an epic fail.
"Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
Sounds like "Vapour ware" to me ;)
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