What I found more compelling was the concept of self-assembly and self-reconfiguration, rather than the lego-like MIT digital materials in the link I gave before: http://cba.mit.edu/docs/papers/06.09.digital_materials.pdf Was this the MIT digital materials you referred to? If not, can you tell us what you were referring to?
NadineJ -- I think the "more compelling" concept is a matter of timeline. The MIT papers do like digital assembly similar to Lego blocks. An article in Wired in recent months discussed a method being used to construct skyscrapers in China in two weeks using a modular approach.
We have seen the open software approach be applied to hardware in the Arduino and BeagleBone and the modular shields we stack upon them. Xerox PARC has done work on 3D printing of circuit boards. These concepts are making traction in the marketplace already.
Ann's earlier article http://www.designnews.com/author.asp?section_id=1392&doc_id=261138 seems to be more futuristic where objects act like (maybe become?) living organisms and adapt their shape and purpose to the environmental need at hand. Science fiction such as the Transformers movies always inspires invention of the future.
Nadine, I googled "MIT digital materials" and came up with several links that seem to be talking about LEGO-like "printing", although it looks more like assembly to me. At the micron level described in a 2009 paper http://cba.mit.edu/docs/papers/06.09.digital_materials.pdf one might be able to call this "digital assembly," but at larger scales that terms seems misleading. Is this what you were referring to?
In any case, it seems to be related to self-assembled and self-reconfigurable devices and materials, on several scales, which DN covered here: http://www.designnews.com/author.asp?section_id=1392&doc_id=261138 and which I find much more compelling.
It's important to remember that the technology for SLS with metals and with plastic is not the same, so it's not a matter of a 3D printer company using one line of printers for either materials set. It's also a really different expertise set. So far, plastic-based companies like Stratasys are partnering with metals-based companies like Optomec, and 3D Systems has bought the expertise.
At IMTS last week, Stratasys introduced two new multi-materials PolyJet 3D printers, plus a new UV-resistant material for its FDM production 3D printers. They can be used in making jigs and fixtures, as well as prototypes and small runs of production parts.
Plastic bags can become useful as either raw materials for plastics or feedstock for fuel. It's when they're not recycled that they become a major problem. That's what California's bag ban will prevent.
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