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How Wireless Meshing Could Save Energy

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).)"

3 of 103 comments (clear)

  1. 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.

  2. 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.

    --
    I am billdar, and I approve this message.
  3. 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.