One of the futuristic inventions of the Star Trek universe is the replicator, a device that can make just about anything: such as “Tea, Earl Gray, Hot.”
Replicators aren’t in the offing, but the next best thing is: a self-copying rapid prototyping machine.
The idea of a machine that can make a variety of objects, including copies of itself, was first seriously studied by John von Neumann in the 1940s (he called them Universal Constructors). His work appeared posthumously in a 1966 book, The Theory of Self-Reproducing Automata. (In fiction the idea goes back at least as far as Karl Copek’s 1921 play R.U.R., which also gave us the notion of robots.)
The closest we’ve come to such devices so far are rapid prototype machines, essentially three-dimensional computer printers. They’ve been used since the mid-1990s by industry to make a variety of complex components for everything from automobiles to hearing aids. They turn a digital blueprint into a real object by building up layers and bonding them together, either by fusing them or with glue.
Existing 3D printers are very expensive, costing close to $60,000 (Canadian). But what if they could make copies of themselves? Then the price might fall to something almost as low as regular computer printers.
Enter Dr. Adrian Bowyer, a senior lecturer in the Department of Mechanical Engineering at the University of Bath’s, working in the Biomemetics Research Group. He’s attempting to create a replicating rapid-prototyper. Not only that, he won’t take out a patent: he plans to make the machine’s design, software and documentation freely available online. He even hopes to supply kits to build the things, at cost.
This will allow users both to build their own machines and contribute improvements, just like users of the Linux computer operating system. Over time the machine will evolve, as users make improvements and create specialized versions for specific tasks.
Dr. Bowyer came up with the idea last February, and has been identifying and addressing the challenges involved. Just recently, he figured out how to lay down conducting materials in three dimensions without a laser.
In a conventional 3D printer, circuits are made of powdered metal fused together by a laser. Bowyer’s idea is to get around the need for a laser by instead using a low-melting point alloy of bismuth, lead, tin and cadmium that can be heated in a syringe and squirted where required.
Bowyer and his colleague Ed Sells have already used this system to wire the circuits into a small autonomous robot, which was itself created using an existing 3D printer. The syringe they used is very similar to the nozzle used to squirt plastic in current 3D printers, so they don’t see any great barrier to using the same nozzle to squirt both plastic and metal components in his future self-replicating machine.
Bowyer’s proposed self-replicating machine wouldn’t be able to assemble a new copy of itself, but it could create and wire circuits into the various parts, which a human could then put together. A few things, like microprocessors and lubricating grease, would have to be added separately.
And what would you do with one once you had it?
Well, you could use it to make a wealth of everyday objects for just the cost of the raw materials. Plans could be downloaded over the Internet, or you could design your own. Want a different pattern of dishes for that big party next weekend? Program your refrigerator-sized mini-factory, and out they come. You could probably recycle them when you were done with them, too, and use the plastic to make something else.
The machine wouldn’t be able to make glass items or complex parts, or (obviously) things that work under intense heat, like toasters. Constructed items could range from just a few millimeters to 300 millimetres in length, width and height, and larger items could be made by clipping together smaller parts. All the owner would have to purchase would be the plastic and low-temperature alloy; production would take anywhere from a few minutes depending on the size.
Musical instruments, furniture, tools, the body of a digital camera–the possibilities are limitless.
“The most interesting part of this is that we’re going to give it away,” Dr. Bowyer says. “At the moment an industrial company consists of hundreds of people building and making things. If these machines take off, it will give individual people the chance to do this themselves, and we are talking about making a lot of our consumer goods–the effect this has on industry and society could be dramatic.”
No kidding.
