make a summary of 3-D printers

Crosscurrents 3D Printers Are Adding a Whole New Dimension to Design by Grant Buckler We tend to think of printers ax devices for producing two-dimensional paper output. In this March 2010 Globe and Mail article. Gru Huler surveys Canadian research in 3D printers and their global application Joint replacements, like artificial knees and hips, are increasingly common. They're a boon for people with fail ing joints, but the replacement parts aren't as durable as the originals. Usually made of metal and plastic and often cemented to the bone, they can deteriorate and come loose, and usually need replacing after 20 to 25 years, But what if implants were made from materials that would actually allow bone and cartilage to grow into them and eventually replace them? A University of Waterloo research lab, with Toronto's Mount Sinai hospital and University of Toronto, is working on it. It's one example of the innovative things Canadian researchers are doing with rapid prototyping, also some- times referred to as three-dimensional printing Printers work by depositing toner or ink on the surface of paper. Three-dimensional printing doesn't stop at one layer. These machines lay down layer after layer of material - it may be in liquid or solid form-to build up an object. As the name rapid prototyping implies, 3D printing has mostly been thought of as a relatively quick way to make models of products in the design stage. But 3D printing is good for more than prototyping, says Dr. Ehsan Toyserkani, a Waterloo associate professor of mechanical and mecha. tronics engineering, director of Waterloo's Rapid Prototyping Laboratory and one of the researchers in the artificial implant project. For an artificial implant to really become part of the body, it must be made of material that the body can absorb without harm and be porous enough that tissue can grow slowly into tiny cavities in the artificial part, It's one thing to machine the outer shape of a part out of suitable material, says Mr. Toyserkani, but we cannot actually control internal structures. That's where 3D print. ing comes in. Because it builds up the part in layers rather than carving it out of a block of material, this process can easily leave openings, or pores, throughout the part. Implants produced this way have been tested in ani- mals, Mr. Toyserkani says, and the researchers hope to move on to human trials soon, with clinical use possible in three to five years. Researchers in Montreal have put 3D printing to an entirely different use Philippe Lalande and Martin Racine are associated with Hexagram, the Institute for Research/Creation in Media Arts and Technologies, which is supported by Concordia, Universit du Quebec Montreal, Universit de Montreal Me and commercial sponson Mande system interested in rapid prototyping when i was exploring sustainable design So they embarked together one of projects ing rapid prototyping and table design The first was Preco, which explored the idea of mig consumer products last longer by wing 3D printer to make replacement parts on demand Too many household gadgets are thrown away because replacement parts are hard to find, Mr Lalande explains there were 3D printing machines in hardware stores and parts carried code num bers allowing a store employee to download the design for a part people could get replacement parts at local stores much as they get keys copied today "We found that basically it was a practical scenario,"M Lalande says. "but to be really effective products would have to be designed from the outset with the idea of their being replaced with rapid prototyping So in their Metamorphose project the researchers moved on to designing products that could easily be repaired and adapted to other purposes. Using rapid proto- typing. they created a series of light fixtures able to be altered to fit different locations and lighting needs, or even turned into other objects - lamp shade becoming a fruit bowl, for example After seeing how difficult these adaptable designs were Mr. Lalande and Mr. Racine decided to launch an adaptable design contest. Thelt year-old Metacycle contest has brought more than 130 entries, some produced using rapid prototyping Rapid prototyping plays a role in other research work. At University of Calgary, Dr. Simon Park of the Mechanical and Manufacturing Engineering department use it to create larger-scale models of nano-scale designs such as tiny pumps. Carleton University set up a rapid prototyping lab several years ago with machines available for student and researcher use The Waterloo labis also exploring the use of 3D printing to manufacture tools with embedded sensors that can measure factors like heat and impact. Today such sensor are usually placed on the surface of the tool Dr. Toysertari says. Readings would be more accurate with the sensor built in, but that's hard to do with traditional manufacture ing methods. Three dimensional printing could be the answer Discussion Questions 1. Can you think of other uses for 3-D printee? 2. Do you expect 3-D printers to eventually be included in home computer systems