Distributed Sensing for Everywhere

E-mail Stephanie vL Henkel

West Virginia's coal-mining country was back in the news recently. This time (semi-joy) it's not dead miners. It's sick school children. The televised report was a tad slow in catching up to a study on those kids published last year, but at least it's getting some attention. A couple of days ago I read the some page proofs of our July cover story, "The Sensor Web: Distributed Sensing," by Kevin A. Delin of SensorWare Systems Inc. This technology could help the miners, their children, and the rest of us.

Coming to You in July
Let me give you a brief preview. The SensorWeb technology, developed at JPL, consists of a bunch of sensing pods that report to one another and, if so configured, to a central data collector and annunciator. These pods have been successfully deployed in some really rough areas—buried in a snow pack and dropped into a collapsed-structure training facility. In the latter exercise, the pods were instrumented with gas and tilt sensors that advised search and rescue crews and their commanders of hazardous conditions, either pre-existing or the result of rescue activities.

Back to West Virginia
Marsh Fork Elementary school in Sundial is a small, single-story brick building serving maybe 230 students. Of those, 88% were found to have respiratory problems, nausea, or headaches that seemed to clear up once the kids had been home for a while. The parents spoke of "dust, coal dust, unusual smells, noise, or blasting from the coal mining site located behind and above the school."

Get this: Right behind the school stands a 16-story coal silo. The residents of Sundial who were interviewed for the TV snippet asked simply that the school be moved. The mine owners' plan is slightly at odds with that request—it intends to build another silo beside the existing one.

Is It the Air?
It does seem probable that emissions drifting from the silos are making the Marsh Fork children feel under the weather. But fairly regularly I run across a news story about some other school with a mysterious outbreak of the woozies. Even the faculty's been known to come down with this malaise. Office workers slump over their desks with heavy-lidded eyes. And don't forget "cabin fever," known mostly in the colder regions where houses are so tightly sealed against the outside weather that the supply of available oxygen dwindles and the inhabitants go at it hammer and tongs along about February.

Or It Is Algebra?
In many of those schools—schools far removed from coal mining operations—the prospect of an algebra (or chemistry or French or you-name-it) exam can lead to the sort of teen crumble that occasioned what happened at Salem, Massachusetts, in the 17th century. Anxiety is extremely infections, maybe even contagious—a clammy handshake from a classmate might spread it too. As for office buildings, sometimes it's deadlines, or an unvarying routine, or new carpeting installed over the weekend.

And Then There's the Rabbit Act
Whenever some fumble-fingered student (or researcher) drops a micro-bead of mercury onto a lab bench, or a child pulls a bottle of nail enamel solvent off the drugstore shelf and three ounces of the stuff puddles on the floor, yonder comes the HazMat squad all decked out in bunny suits. Is anything scary really happening? I'd sure want to know before hitting the alarm because visits from the strangely attired aren't cheap.

Fast Forward to July
The pods introduced in our July cover story could, assuming a price to suit the general market, be bought and either installed in areas where there's a likelihood of hazardous conditions or kept on hand for surprise events such as the errant mercury bead. In principle, they could be instrumented with sensors to detect any number of conditions. A school thus monitored could, for example, establish whether fainting in the band practice room was caused by cleaning materials stored in a closet next door or stage fright over an upcoming concert. Or that glue securing the new office carpet was outgassing something noxious to the nose.

As for the miners, they might have a few more minutes to get out before a roof or a wall lets go. Or gases come in. Watch for next month's cover story. The technology is fascinating, and the new capabilities it enables could be exactly what you need to satisfy your own applications.