Engineers Spread New Printing Technology

Researchers in mechanical and aerospace engineering have developed an easy, affordable 3-D printer that anyone can build and use.

“This technology has been around for two decades,” said Prof. Hod Lipson, mechanical and aerospace engineering. “Imagine an inkjet printer, where instead of ink, you print out droplets of plastic.”

If you print in the same place repeatedly, the plastic droplets build on themselves, creating three-dimensional objects.

“It takes a couple of hours, but you can make fascinating things,” Lipson said, holding up a star-like cluster of five solid, unconnected but interlocking tetrahedra.

Lipson compared this rapid prototyping technology to computers in the 1970s: commercial units are large, expensive, complicated and difficult to modify.

“With commercial machines, you open it and you can’t touch it. They’re not hackable. They’re preventing their own progress,” he said.

“What broke the cycle in the 70s was the Altair 8800 computer kit.”

The Altair 8800 was a simple kit with which hobbyists could build and customize computers for a reasonable price. It spurred the development of software, operating systems and user interface devices. It is regarded as the precursor of the personal computer. Lipson and several graduate students have developed an equivalent kit for rapid prototyping, called “Fab@Home.”

“Fab@Home is an attempt to make multi-material rapid prototyping accessible to anyone,” Lipson said.

“The idea was to make the whole thing open-source, and the backbone of that is the wiki,” said Dan Periard M.Eng.’ 07. Lipson said that the Fab@Home site consistently gets about 20,000 hits a day.

“All the parts are off-the-shelf,” Periard said. “We designed it so you can expand. We have a Google group with people just throwing ideas around.”

“People are making these already,” Lipson said. About a dozen people have said that they are building the kit, and there are three operational models, or “fabbers.”

A group at Rockefeller University has used a Fab@Home fabber to study slime mold organisms and a family in Kentucky has customized its device to print chocolate from a heated syringe, said Evan Malone, grad., designer of the Fab@Home kit.

[1]Pioneer printing.: Evan Malone grad showcases the Fab@Home 3-D printer, the printer of the future.

“This is a quick and easy solution for [custom] parts in labs,” Malone said. Rather than contracting outside companies to make small parts, they can be easily manufactured with Fab@Home.

“We’ve also had a lot of interest in artistic applications,” he said.

The fabbers are designed to work with any soft material that can be squeezed out of a syringe. “EZ-Cheese and peanut butter are pretty nice,” Periard said. “You can use, say, cheese to bang out a prototype model in five minutes.”

“The only limitation is if you build up high, the material needs to hold itself up,” Periard said.

“Fab@Home is really an outreach project for us,” Malone said. The goal of his research is “to prove the principle that you can 3-D print complete electromechanical devices without human intervention.”

“We’ve already printed a working battery,” Malone said. Eventually, he hopes to print a complete functioning robot that will walk out of the fabber.

Malone said that in the future, fabbers could have applications in space exploration, where delicate technology has always lagged behind the state-of-the art because it must be able to withstand high radiation levels. Instead, by placing a fully automated fabber on the surface of the moon or Mars, cutting-edge technology could be manufactured in-situ and would not need to be radiation hardened. If it fails, a new one can be printed.

Closer to home, Lipson believes that fabbers will “change the way we consume things, just as MP3s have changed how people buy music.”

Rather than purchasing products, people will download blueprints and manufacture their own. “You could even build a big version and print out furniture,” Lipson added.

“It’s a lot of fun to sit at your desktop and think of what you can make,” Malone said.