The Networked Physical World
Down in the trenches of MIT's famous Media Laboratory, Associate Professor Neil Gershenfeld is reflecting on the bits and the atoms. "The bits are the good stuff," he muses, referring to these units of digital information. "They consume no resources, they travel at the speed of light, we can copy them, they can disappear, we can send them around the globe and construct billion dollar companies." Contrasting them with physical objects, he says, "The atoms are the bad stuff. They consume resources, you have to throw them away, they're old-fashioned." A challenge for the millennium, he explains, is to find ways to "bring the bits into the physical world."
The basic idea behind linking bits and atoms is finding ways of getting physical objects to communicate with computers through a digital network. Technologists see this as a way to liberate computing from the confines of the PC and bring it out into the world at large. John Seely Brown, the chief scientist at Xerox, compares computing today to "walking around with your peripheral vision blocked by a pair of tubes on your glasses." And Gershenfeld says the problem with PCs now is that they only touch that "subset of human experience spent sitting in front of a desk." Both scientists say that to be truly useful, computers should be brought into the stuff of everyday life, in part by embedding them into ordinary objects and machines.
These advances will usher in a new era of ubiquitous computing, in which inexpensive servers bring Internet access to household appliances and office equipment. People will take for granted that microwave ovens download cooking instructions from the Web or that alarm clocks reset themselves after a power outage. The cheapest gateways to the Internet will comprise sensors and radiofrequency (RF) tags linked to networked microprocessors. An RF tag is actually a silicon chip that emits an electronic signal in the presence of the energy field created by a device called a reader. Tags already have some familiar uses -- for instance driving through an automatic toll booth causes an RF tag to boot up and identify your car.
In the near future, by linking them to the Internet, tags and readers will open up new worlds of opportunities. Conceivably, "smart" fridges could monitor tagged products, learn your food preferences and shopping schedule, and eventually buy all your groceries for you. Washing machines could monitor colors -- toss a tagged red sock into a pile of white laundry, and the machine will shut down. Tagged pill bottles in a medicine cabinet could allow doctors to monitor patient compliance with prescriptions, remotely.
One group working to blanket the consumer marketplace with this technology is the MIT-based Auto-ID Center, a consortium of academic and industry scientists seeking to replace bar codes with a system that tracks manufactured products with pervasive grids of readers in warehouses, trucks, stores, and the home. Once the infrastructure is operational, companies will be able to determine the whereabouts of all their products, all the time. This capability could provide some important environmental benefits: real-time product tracking will enable manufacturers to save millions in cash and energy resources by shifting to a process that matches production to consumption, item for item. And tagged products could also become self-managing; able to convey their identity and composition to networked trash containers and recycling centers.
In another bit of futuristic innovation, scientists are devising ways to ship bits rather than atoms to manufacture products remotely. Someday, printers called "personal fabricators" will be used to make things like toy jeeps and wine glasses in the comfort of your own home. Scientists at the Media Lab are already printing semiconductors, transistors, and other electronic devices as if they were made out of paper. Simple three-dimensional objects have already been printed as well, with more complicated structures just around the corner.
Gershenfeld suggests personal fabrication has both an environmental upside and downside. On the one hand, the technology could save energy by reducing energy expenditures involved in transporting a product to its point of use. On the other, three-dimensional printing could inundate society with objects, in the same way the "paperless office" is in reality saturated with more paper than ever. The only way the personal fabricator could become environmentally feasible would be to equip it with a "defabricator" that breaks objects down to their constituent materials.
Next section: The Future of Remote Sensing