An Underground Radio to Save Lives

Roland Piquepaille writes "The Duluth News Tribune wrote last week about a communication device which could be a lifesaver for miners. This invention is the brainchild of David Reagor, a physicist at Los Alamos National Laboratory (LANL). His prototype radio works at depths of 500 feet and is based on very low frequency electromagnetic radiation and digital signal processors. A commercial version is in the works and could be used not only by workers trapped in a mine, but also by firefighters and other emergency workers to communicate with people in collapsed buildings or subways."

Comments

Sound familiar

[CCFreak2K]

Sounds like something I saw in Dante's Peak. No pun intended.

Re:Sound familiar

[ozmanjusri]

Sounds like something I saw in Dante's Peak.

We've been using underground radio in Australian mines for decades. Leaky feeder systems are common in most mechanised mines, and personal emergency devices (PED) are available that use ULF signals to transmit text messages through the ground. If this guy has found a way to encode voice as well it's an improvement, but not groundbreaking (pun intended).

VLF has been used for submarines for decades

[ishmalius]

Very low frequency (VLF) has an extremely low data rate, yet it has a great ability to penetrate earth and water. The Navy has been using it for a long time to communicate with submarines.

Re:VLF has been used for submarines for decades

[Stellian]

It seems pretty extreme to me to receive a 1 million $ grant to build what is basically a long wave radio coupled with a CELP encoder (these can compress voice down to 1200 bps).
I'm sure there are lots of practical difficulties though.

Re:VLF has been used for submarines for decades

[skogs]

It seems you do not understand VLF/ELF ideas. The entire point is that it is a super low frequency. Low frequency doesn't cycle very often, and makes it hard to press data...so it would be rather difficult to compress audio and then send it.

The navy's ELF is just that...ELF...it sends text only. This is no email system, this is exactly what needs to be sent, and thats it...and some messages take several minutes to send. Sending voice data would take an extremely long time...and transmitting for that long wears down batteries. Your LMR(land mobile radio) be it motorola, etc, MIGHT last an entire day or 8/12 hr workday...but it only gets keyed for about 20 minutes of that timeperiod, if that.

I think, even if it was VLF instead of ELF, they would be far better served to make a keypad, and force people to type short messages to transmit. That way it might actually last for 3 or 4 days if there were an emergency. Otherwise it simply wouldn't have the power to maintain sporadic communications for that kind of timeframe.

Re:VLF has been used for submarines for decades

[Slugster]

Yes--the international VLF emergency code is three long five-second blasts of brown note noise, which indicates "send toilet paper immediately"
(them's "bog rolls", for you non-American speakers)
~

Re:VLF has been used for submarines for decades

[lampajoo]

Speech compression algorithms by using linear prediction and other tricks can reduce the bandwidth required for transmitting speech by a factor of 8 with no perceptible quality loss. You can reduce the bandwidth required even more by taking a quality hit. Also, the latency in a voice conversation can be quite high(500ms or more) before anyone will notice that there is a delay. I expect that a miner that was trapped would not care that much if while he was talking to the rescuers that the sound quality was poor and it took a few seconds for the response to come.

If you used the bandwidth from all of ELF and SLF...not sure if that's feasible or not, you would be short by a factor of 10 (if 300hz-3hz=297 and hz=> 297bps and the speech requires 2400 bps) which could be used for a "store and forward" radio...like underground voicemail.

Troglographs are not new

[TechyImmigrant]

Troglographs are not new.

wait a second.

[mattpointblank]

"A communication device which could be a lifesaver for miners"? We already have Myspace.

Wait, miners? Oops.

Fact of the matter is...

[nitrocloud]

In recent mine collapses, two things were needed in the mining tunnels, oxygen, and communication. Without oxygen, humans die. Without communication, humans are lost in a large mine shaft with relatively no way to signal those above of where ventilation shafts can drilled to vent toxic gases and supply oxygen. The truth is, communication is vital, and the lack thereof has been proven deadly, with this radio, perhaps mining accidents don't become mining tragedies in the future.

Re:Fact of the matter is...

[Dr. Evil]

If you don't make it to a refuge station, you're dead anyway.

Mine refuge stations are fed with high-pressure air lines. If those lines get damaged, you probably won't survive long enough for anyone to sink down new lines.

I can't imagine this kind of communication helping much. People don't wander mines aimlessly. After a cave-in, they're either at the job site, the refuge station, or somewhere in between. If they're on the surface, then their tag wouldn't be on the tag-board.

Maybe at best, a device in a refuge station to signal that yes, there are some survivors. But if you're rescuing and you don't get a signal, what do you assume?

In other news

[protich]

Apple is already working on a nano ipod for miners which comes with a radio,video, music. Code named "underground". You can also connect to iTunes!!

Re:In other news

[rossdee]

Odly enough, I heard that among the essential supplies sent through to the trapped Australian miners (along with food water and air) were Ipods. I guess they could listen to that BeeGees song (New York mining Disaster)

Not deep enough.

[blair1q]

South Dakota's Homestake gold mine is 8,000 feet deep. 16 times deeper than this thing can reach. What's needed are acoustical communicators that can ping through the rock with a coded signal telling the miner's location. But given the safety record of mine operators, they won't update the codes as new side-tunnels are dug, won't keep the batteries charged, won't keep the receivers in working order, and won't train the safety personnel.

Re:Not deep enough.

[onebuttonmouse]

It says right there in the summary that the thing is just a prototype, surely it's possible to communicate over greater distances using a more powerful transmitter.

Re:Not deep enough.

[Beryllium Sphere(tm)]

On other other hand all it has to do is to reach a level with a repeater and power. A disaster that wipes out everything in a 2000 fout radius in all directions would not be a resonable design case.

As regards your allegations about mine safety practices, you are (pardon the phrase) dead right.(*)

(*)Useta live in West Virgina. Study the history of coal companies before you call anyone in high-tech "evil".

Re:Not deep enough.

[Reverberant]

What's needed are acoustical communicators that can ping through the rock with a coded signal telling the miner's location.

I'm not sure that acoustics is the answer here, especially if you're talking about an 8000-ft depth. Acoustical waves travel well through rock, but exciting the rock in the first place takes a lot of force. As a comparison, ground-borne vibration propagation test equipment (used for train vibration assessments) typically put out peak forces in the 6,000 to 10,000 lbs range, and the signal is barely detectable using averaging methods at 200 ft.

You could try signal processing tricks (MLS for example, self-link to a PDF paper I wrote), but then you're trading in the peak force for massive computing power at long distances- I'm guessing several hours of number crunching for a top-of-the-line PC for several thousands of feet of depth, maybe less for multiprocessing workstations if you can vectorize the calculations.

I suspect that an EM solution would be much easier to develop.

Re:Not deep enough.

[hyperstation]

(*)Useta live in West Virgina. Study the history of coal companies before you call anyone in high-tech "evil".

agreed. i'm in wv now.

Re:Not deep enough.

[Tau Zero]

Don't trapped miners already beat on the walls to signal their position? I distinctly recall reading that the Sago miners did just that.

Re:Not deep enough.

[YrWrstNtmr]

South Dakota's Homestake gold mine is 8,000 feet deep. 16 times deeper than this thing can reach.

In other words..."Holy crap. This thing is not useful in every possible situation imaginable. Therefore, it is totally useless. Let's try something else that may or may not work."

Jebus, dude..calm down. Here's a new use for an old technology. Let's see what it can do before we blow it off completely.

Re:Not deep enough.

[lukej]

Having been to the 8,000ft level of Homestake, I'll confess, it is spooky! Radios would be nice.

However, deeeeeep mines (gold in Homestake's case) are probably vastly out numbered by 'shallow' coal mines in the Eastern US.

As a side note, /.'ers should help lobby to turn the now defunct Homestake into one heck of a laboratory...

http://neutrino.lbl.gov/Homestake/LOI/
http://www.state.sd.us/homestake/
http://en.wikipedia.org/wiki/Homestake_Mine_(South _Dakota)

Nothing new here

[n1ywb]

As usual, there is nothing new under the sun. Cave radios have been under active development for some time. Check out these resources

Cave Radio & Electronics Group
Google "Cave Radios"

Granted this guy's sounds a little more advanced with DSP and stuff, but still not a new concept.

Re:Nothing new here

[noidentity]

"As usual, there is nothing new under the sun."

Yes but this is for use in mines where there is no sunlight. Big difference.

How about a standing wave?

[TubeSteak]

Would it be possible to just setup a standing wave between the surface and some underground node? To chat, all you have to do is modulate the wave. Right?

Low power (cheap) underground radios talk to the underground node.

Or am I missing something obvious... /Radios & antennas are not my forte

Re:How about a standing wave?

[josecanuc]

Or am I missing something obvious...

Radio waves don't travel too well through rock/soil. The very long wavelength (hence low frequency) of this proposed product would theoretically be less absorbed/reflected by the rock and soil, but I can't imagine it being any significant amount more effective than existing VHF/UHF radio systems.

In my opinion, the most effective and also the cheapest way to communicate with miners is with copper. I mean, if you can get people down there, you can certainly get a cable down there, too. Right? The telephone system has proven the effectiveness of "landline" communications.

partially a matter of economics

[fermion]

The talk lately has been that plenty of technology exists to help in rescue efforts and insure the trapper persons survive until rescue happens. The probelm seems to be funding for production, the market for these devices is very small, following existing safety regulation, and training. THE VLF frequency radio is nothing new, and this just seems like a way promote the technology and encourage the federal authorities to mandate the device, and probably use tax monies to partially fund the deployment. I don't know why we would want to do this insted of enforcing the current regulation, perhaps raise fines on violation, and, if we want to be realy radical, actually expect the fines to be paid. In fact USA Today, which I am lothe to quote, seems to think that the current rash of accidents are a result of lack of enforcement over the past several years, and not the direct result of the lack of any safety equipment. I know that I would much rather be at the dinner table with my family than trapped in a mine, even if I did have the ability to say goodbye with my last dying breath, and with the full knowledge that the mine company will get the digging equipment in as soon as humanly possible, and would pay the $5000 fine for the accident, if it survived the appeal.

Which is not to say that accidents never happen, but when a mine has been cited at nearly every safety inspection, and has not paid fines, one wonders whether more safety gizmos are really going to do any good.

Re:partially a matter of economics

[Bishop]

In North America there is a cycle in mining safety. As a result of accidents authorities impose various safety regulations. After several years of safe mining the companies point to their safety records and convince authorities that certain regulations are no longer needed. After the regulations are relaxed (or no stop being enforced) serious accidents happen.

Is this what they used in "The Core"??

[SeaDour]

I was always annoyed by the fact that, though the movie tried to be vaguely scientifically accurate, their ability to communicate with the people traveling thousands of miles beneath the earth's surface seemed magical at best. Maybe it was something like this!

Re:Is this what they used in "The Core"??

[thePig]

The CORE ?? Are you sure?
Check out http://www.intuitor.com/moviephysics/core.html

that's great

[hyperstation]

now try convincing profit-oriented mining companies to buy it. they're scum.

Re:that's great

[cheekyboy]

Your pc wouldnt be here if it wasnt for metals from mines.

And the electronic companies charging 900% market arent scum? Where as gold miners HAVE TO SELL their
gold at spot price, not 900%. The sell price is fixed, your margins are determined by your
mining efficiency and labour and stupid local govt whores+taxes.

Re:that's great

[hyperstation]

i'm referring to underground COAL mines, not metals.

Not deep enough

[ajdlinux]

Here in Australia there are two miners trapped around 935 metres (3116 ft) below the ground. They managed to contact them using existing radios. Fact is, most mines are deeper than 500ft.

Re:Not deep enough

[ajdlinux]

Sorry, meant 3067 ft.

Developped in caving activities up to 1Km deep

[zijus]

Hi there.

You better check that out : systeme Nicola. I don't put a hand on publishing date, but some folks in Europe are developing such a system for a while. They are aiming at caving rescue activities. In specific conditions they got the communication through 1000 m of rock. Interesting. Funny as well to get a feeling on how polluted can be our environment in the low frequencies realm.

Bye. Z.

Re:Developped in caving activities up to 1Km deep

[scdeimos]

This sounds impressive until you read the specs, which include:

Antenna : Large virtual loop constituted by the two electrodes connected to earth spaced by 40-80m

Miners trapped underground will often be lucky to have any more than 2-5m to move around and lie down to rest in.

Re:Developped in caving activities up to 1Km deep

[zijus]

Good point. Also, AFAIU the system described in the article do not need grouding: the two systems do not use the same principles. One is based on electromagnetisme, the other on earth conductivity. So, I was a bit hasty at meaning they are similar. That is also the reason why one is limited to 500 feet range while the other can reach through up to 3000 thick rock.

Bye. Z.

Wouldn't help

[Beryllium Sphere(tm)]

A standing wave is just a traveling wave that gets reflected. It would have all the same aborption problems as any radio system on the same frequency going through the smae materials.

Re:Roland spams Digg too

[mindtriggerz]

Rationality is not permitted on Slashdot.

Coming from a coal mining area..

[Winlin]

it's good to see any new advances in mine safety. I'm only about 50 miles from the sago mine area, and i live literally a stones throw from an old ( now reclaimed) deep mine. A walk through any graveyard around here will show how dangerous mining has been over the years.
    On a side note, am i the only one who saw the article title and wondered what some pirate radio station would have to do with safety??? Probably so.

Make that armored copper

[Beryllium Sphere(tm)]

Refine that further, and combine copper with radios. I was chatting with someone on another site who pointed out that you could use badly shielded coax to extend the range of radios. If you're trapped away from the nearest phone but have intact leaky coax within range, then when you key your radio the signal leaks into the coax, and then leaks out everywhere else including (maybe-let's-hope) the area where uninjured personnel are.

Leaky coax is a commercial product, sold under the name Radiax. I know someone who got the same effect for less money by buying allegedly fully shielded coax from Radio Sh***.

Re:Make that armored copper

[solitas]

You'll probably still find "leaky coax" hanging on the streets of some universities - low-power FM broadcasting used to use it: as long as you didn't exceed a certain field strength at a certain distance from the wire you could run 'em as far as you could afford to cover an area/street/campus.

Re:Make that armored copper

[ColaMan]

That's exactly what we use undergound - leaky feeders with repeater/amp modules every thousand feet or so. Coupled with standard VHF radios it works ok. It also carries a "PED" - a one-way text pager that's embedded in the battery pack for my caplamp.

But yet, it's still a pain in the ass. If you cant see a leaky feeder hanging from the roof, there's no comms. It's strictly line-of-sight. Even though it's armoured cable, a ton of rock will easily crush it.

So forget using leaky feeder cable for rescue.

If I could just get a text pager that worked outside the range of a leaky feeder, I'd be happy. This looks like it might be a solution.

These are not radios

[EmbeddedJanitor]

They work by induction loops (ie are magnetic). They are not radio. Induction loop comms predates Marconi. The big challenge with VLF is to make a big enough antenna.

Can be made to work

[EmbeddedJanitor]

and mines in South Africa go much deeper than that.

Most rockfalls leave the main shaft ok. You could run a cable down the shaft and have "access points" at vaious depths etc. The VLF only has to cover the last bit to the actual miner.

Lifesaver for commuters, too

[ozbird]

As loss of radio contact was one of the factors the resulted in Jean Charles de Menezes being shot dead by police, radios that work in the Underground ("tube") as well as underground would be a good thing.

Re:Lifesaver for commuters, too

[AB3A]

Uhh, radios DO work in the "underground." The Metro in Washington DC does this, as do many other subway systems. The technology has been around since at least the late 1970s. It's really quite simple: A leaky coaxial cable (Andrew Corporation makes one called Radiax) can be used for both receiving and transmission. If what you say is accurate, the folks managing the London Underground could really use an education.

Now as for mines, such systems are useful for tunnels which don't change much, such as underground railway tunnels. Engineering these systems on an ad-hoc basis isn't simple, nor cheap. Mines need to use something better. A robust digital modulation scheme which can survive multiple repeating nodes with less than ideal signal to noise ratios is something which needs development. Ideally this system would use something robust like turbo-codes, where a damaged packet could be recovered with some delay.

This could result in some messages taking many seconds to get to and from the surface, but at least they'd get there...

Re:Lifesaver for commuters, too

[Detritus]

Conventional police radios will work in the subway system if the proper equipment is installed. The Washington, D.C. Metro system has a radio system that works in the underground stations. They string "leaky coax" through the stations and tunnels.

Three cave radios

[Anonymous Coward]

I'm aware of these three underground radios:

- The MolePhone
- The HeyPhone
- System Nicola

I believe they all operate at around 87 kHz. The Mole Phone has been around for 30 years or so; the others are newer and more high-tech, with greater range.

Grintek Mine radios

[HermanAB]

Mine radios used to be manufactured by SAAB Grintek, but was sold to a company called Guduza, which promptly disappeared without trace.

These radios used a 100kHz carrier and was basically inductive radios, using the shoulder strap as an antenna. It could penetrate 100m of solid rock. During that journey, it would typically find some piece of metal - pipes, railway tracks, whatever - couple to that and provide communications throughout an underground mine.

So it seems that this guy is re-inventing 1970s technology. It is a proven concept and should work well.

Re:Roland spams Digg too

[Linker3000]

Maybe a slip-up - do a Digg search for 'primidi' (his blog site) and see how many 'different' people have submitted stories to Digg linking to that site (I counted 18). Surely Roland isn't posting under numerous different account names? I'm shocked, SHOCKED!

Alternative solution

[LiquidCoooled]

I believe using RFID in mines would be beneficial.
For every 10 metres of tunnel dug a scanner is placed.
Every miner has a tag about their person which triggers the scanner by moving past it.

If an incident occurs, the miners exact location in the *old* tunnel network is ascertained.
Sure, the rock might have moved since, but its a much better starting point than nothing.

Re:Alternative solution

[Anonymous Coward]

This seems like a great idea until you think about:

- the fact that every scanner will need a hard line back to whatever computer system is collating the data (or at least a radio bearer which it can communicate with).
- the maintenance overhead of say an average small mines crew of about 150 undergrounders needing to make sure their RFID tag is working every day and fixing them if they are not.
- All this gear having to work in an environment which is incredibly tough on equipment. For example, your RFID scanners would need to be able to withstand nearby explosions, or your miners would fall into the habit of not placing them on freshly blasted areas because when they blast the next section they would destroy the previous area's scanner - but the sections being blasted are usually the most hazardous.

In *good* mines the crews already have good knowledge of where their mates are working, the supervisors track the locations of their crews well enough, and in the event of accidents usually it is known approximately where the trapped miners are. In bad mines - well they aren't going to fork out millions of bucks for a fancy RFID setup are they.

There are three places to focus the technology that are useful IMO:
1. Technology to help manage risks and prevent accidents (for example - tele-mucking where remote controlled diggers are used in dangerous locations, better understanding and monitoring of seismic activty etc).
2. Technology to help detect exactly where people are - when you are blasting and drilling through a cave-in 10 metres is actually a long long way. Some sort of PSD which could be activated in the event of an emergency (perhaps based on ELF or this device) could also be very handy in pinpointing location.
3. The mine managers notebook - so that he/she can't deny they saw the 10 emails from the supervisors about their concerns with respect to tunnel 12 etc.

VLF for data transmission is old hat...

[csoto]

http://tf.nist.gov/stations/wwvb.htm

Devices could easily be designed to carry data such as percent oxygen, number of heartbeats present, nearest locator beacon, etc. Very low data rate, but still good enough to get this sort of quick-and-dirty textual stuff through...

60s radicals had underground radio

[Jerry]

and they used it to communicate their activities to each other. It could reach for miles and had the police confused since they couldn't figure out how the radicals were communicating.

It was easy. They took high powered audio amplifiers and connected the wires which would have gone to speakers to steel rods driven into the ground several feet apart. I don't remember exactly how far apart they were. One could recieve the signals by attaching a sensitive audio applifier to a similar set of rods. IIRC, with 250 watts of output power they were able to communicate 10-15 miles "underground".