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How Wireless Meshing Could Save Energy

Posted by timothy on from the 23-percent-is-a-bunch dept.

An anonymous reader writes "EE Times reports that the future of industrial automation lies in wireless mesh sensor networks. From the article: 'It is the holy grail of the factory floor: hundreds of sensors wirelessly connected, monitoring motors for problems and drastically reducing energy consumption -- all with the precision and rhythm of a philharmonic orchestra.' (Other articles here(1), here(2), and here(3).)"

9 of 103 comments (clear)

  1. Saving energy... by ackthpt · · Score: 4, Interesting
    All I need is some sort of antenna system, tuned to the wavelength of these networks and I could capture the power and run my house off it! :-)

    My dad told me stories of Back In The Day(tm) when AM radio stations would broadcast at 300,000 watts, or more, and streetlights would be lit by the radiant energy. Can't imagine that did people much good living near the antennas...

    --

    A feeling of having made the same mistake before: Deja Foobar
  2. I, for one... by ChaosWing · · Score: 4, Interesting

    ...welcome our new job-stealing wireless mechanical overlords.

    Seriously, though, this would make my job a whole lot easier...monitoring the operation of a pair of 8MW generators (or a host of other equipment) from a single location vice constantly hopping around from point-to-point looking at every little gage and meter gets real old, real fast.

  3. Munchkins...? by nzgeek · · Score: 5, Informative

    This idea strikes me as an implementation or extension of "Munchkins" described in an ancient (1996) paper by Rohit Khare and Adam Rifkin.

    The idea basically describes very small, low-power devices that can route messages between each other until they find the target device (or a valid route to the target device). I have to wonder whether new devices like the iPAQ with GSM, WiFi, and Bluetooth are trending towards this behaviour. It wouldn't take a heck of a lot to turn the iPAQ 6340 into a device that can intelligently route incoming packets over any of its connections.

    I'd love to be able to pick up my cellphone, and connect to my PC via a network of industrial sensors built into traffic signals, bus stops or the nearest ATM.

    --
    gadgetophile.com
  4. Radio Luxembourg, the great 208 had 1300 Kw on MW by GuyFawkes · · Score: 4, Informative

    The station transmitted to all of Europe via the powerful transmitter site in Marnach on 1439 kHz (later 1440 kHz), 208 metres in the medium wave band. The transmitter pumped out 1300 kW and was Europe's most powerful (only hit by a Russian site which had more power). Radio Luxembourg ceased transmissions from the 208 transmitter December 30. 1991 to be available on satellite and short wave only. Unfortunately CLT decided to close the station at the end of 1992 because it made no money out of the programmes. Luxy returned on the great 208 for one night only - the date when the station's final programme was aired - December 30. 1992.

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    http://slashdot.org/~GuyFawkes/journal
  5. Interference? by Godeke · · Score: 4, Insightful

    Having installed wired and wireless networking on manufacturing floors I can tell you that before this dream of magic wireless connectivity comes true, these machines will need vastly better RF shielding. We had a bugger of a time getting wireless to work and even wired networks would act up if you were not careful where you placed the wires. (One company ran fiber optic to the floor machines because the interference issue couldn't be resolved satisfactorily: not a cheap way to go).

    So how long will it take to get those machines updated? Well, one of my first jobs out of the U was making a tape punch work on a PC so they could edit programs and load them from paper tape. That was in 1990. I'm guessing that these will be a great concept for someone building a factory floor from scratch, but retrofitting is going to be a big flop.

    --
    Sig under construction since 1998.
    1. Re:Interference? by IvyKing · · Score: 5, Interesting
      The folks working on this are very aware of the problems with interference - DOE has been working on factory floor networking for several years (Wayne Manges from ORNL). In addition to interference, you have to contend with Dopler shift and fading as a result of objects moving aroound the floor (variable multipath). For those with radio experience (e.g hams) signal propagation starts to look more like HF (shortwave) than microwave.

      but retrofitting is going to be a big flop

      Actually the whole point of this work is to retrofit the factory floors (or other places using large motors). According to Wayne Manges, you're looking at $20 to $50 per foot to install wiring, so a $200 wireless sensor would be cost effective compared to running wire. The system could pay for itself by flagging one motor that is having problems before it fails - DOE's hope is that you can also tell tha the motor is chewing up electricity at an excessive rate.

  6. Intrinsically Safe by billdar · · Score: 5, Interesting
    Two years ago when I was an ASIC engineer, I would have thought this was a good solution. Having since switched to industrial control systems, I have to say no way.

    Safty and reliability are absolutes in industrial control.

    A machine like a bottler goes down at pepsi, and they are losing $250k/min when that machine isn't running. Or a pharmacutical company drops a batch worth $3 million. And now that I've climbed in or on huge presses, mixing tanks, 6ft. fans, high preasure steam, and poison vapors... I wouldn't trust thier function to a wireless web.

    I can see where this would be great for remote/hazardess sensors and transmittion, but not anytime soon for control. Hell, we still extensivly use rs232 over ethernet.

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    I am billdar, and I approve this message.
  7. Re:How secure are such setups? by rcw-home · · Score: 4, Informative
    What prevents a competor with a wireless broadcast anteanna from parking in range of your factory, and sending false signals telling your machines to idle?

    Standardized AES encryption.

    BTW, I'm pretty sure that the article had a typo - they probably meant IEEE 802.15.4 (aka Zigbee), not 802.16.4. The Zigbee FAQ has a lot of valuable information about it.

  8. Re:What about SAR? by ajlitt · · Score: 4, Informative

    Usually, but for most devices under the 2m wavelength mark (>150MHz or so, which these would probably be), human body absorbption drops quickly.
    Of course, this is moot when compared to the EMI that most industrial electrical equipment generates. Hundreds of 3-phase motors, giant transformers, and multi-kilowatt circuits make for a far stronger field at the low end of the spectrum than an army of small sub-watt range transmitters.