Photo: Chris Lockwood

Fabbers—machines that rapidly create useful items on demand from computer-generated design specifications—have been fantasy fodder for decades. And for good reason: a machine that could make a huge variety of reasonably complicated objects, and yet was attainable by ordinary people, would transform human society to a degree that few creations ever have.

To understand why, consider the vision offered by Neil A. Gershenfeld, professor at the Massachusetts Institute of Technology, in Cambridge, in his recent book, Fab: The Coming Revolution on Your Desktop—From Personal Computers to Personal Fabrication (Basic Books, 2005). Gershenfeld describes his ongoing project to equip ordinary folks with machines that were once used exclusively by manufacturers to prototype new designs. With such machines, people can, in effect, "download" such complex objects as bicycles, chemical sensors, radios—and eventually robots, and maybe even prosthetic limbs—much as they now download music and video files.

Fabbers of seemingly unlimited capability also buttress lots of recent science-fiction plots. The "matter compiler" of Neal Stephenson's book Diamond Age (Bantam Books, 1995) is a memorable example. And in Alistair Reynolds's trilogy of space operas, interstellar spaceships rely on fabbers to produce everything from weapons to furniture.

While that kind of capability may be decades if not centuries away, researchers at several universities, including Stanford, Carnegie Mellon, MIT, and the University of Bath, are already investigating technologies and materials that could lead to general-use, compact fabbers. At Cornell University, in Ithaca, N.Y., my group in the Cornell Computational Synthesis Laboratory has taken the first steps toward what we hope will be a significant milestone: the creation of a fabricating system that can produce small, simple robots incorporating a battery, actuators, and sensors. Our goal is to one day see little automatons wriggle, completely finished, out of our apparatus, their electronic and mechanical subsystems having been created in one seamless process—batteries included. In the meantime, we recently succeeded in creating a small fabber that we used to make a coin-shaped battery and an actuator suitable for our envisioned robot.

Compact and yet capable fabbers point the way toward a future where the term "online shopping" takes on a whole new meaning. Imagine purchasing a piece of software that encodes detailed specifications of something and then seeing that object emerge from a box on your desk no bigger than a microwave oven. Like your desktop printer today, this desktop fabber would use some sort of cartridges. And just as desktop-printer cartridges contain the inks that can produce a limitless variety of images, the fabber cartridges would contain the necessary raw materials to create a profusion of desired items.

Not every consumer product is suitable for fabbing, of course, but anything whose materials cost is low compared with its intellectual investment is a contender. A few examples are electric toothbrushes, cellphones, eyewear, toys, costume jewelry, and other decorative items [see sidebar, "Download Museum Pieces Today"].

Although many technical hurdles must be cleared before home fabbing can become a reality, it's already possible to see its huge implications for engineers, designers, and distributors. Manufacturing, at least for things that could be fabbed, would be divorced from rigid corporate control, spawning new classes of independent designers. Much of the stock and delivery costs associated with conventional manufacturing would be eliminated. And with appropriate software, a product could be customized, enabling a system of bespoke production almost inconceivable today.