When WebProNews hit Vegas for the CES 2010 conference, we came across a number of new and interesting gadgets.
The MakerBot’s CupCake CNC is a 3D printer/fabricator that can make just about anything you want. As long as the object you desire can be made out of ABS plastic and stays in a size range of 4″x4″x6″.
Once the design is input using 3D modeling software or by visiting Thingiverse for a pre-made template, MakerBot turns the creation into reality. The machine begins ‘printing’ and soon after, a 3D model of the design requested materializes right before your eyes.
These 3D fabricators are priced between $750-$950 and have qualities that even attracted major companies like Google. The MakerBot representatives stated Google has invested in multiple CupCake CNCs. For what? We can only wonder….
Print-on-demand technology — utilized by companies like Vistaprint and CafePress — has become widely implemented over the last decade as digital printing has steadily replaced costly letterpress plates and other complicated methods. At the same time, 3-D printers (like our favorite, the MakerBot) have become more commonplace in the manufacture of products and prototypes. And, now, biotech outfit Invetech has merged the two technologies, replacing printer ink with living cells. That’s right: a 3-D, on-demand human tissue printer.
Developed for bioprinting company Organovo, the printer contains software that allows bioengineers to build model “scaffolds” on which to place, say, liver cells for a patient in need of a transplant — all before the structure is constructed by laser-calibrated print heads. The printer then builds the tissue layer by layer, much like a traditional 3-D printer.
This will undoubtedly change the game for biotech in years to come. The technology proposes a future in which patients do not need to wait for transplants from other human hosts; instead, medical technicians will simply have tissue models ready to be customized and printed on-demand. And, of course, this will be tons of fun if it ever hits the consumer market (not likely), as we’ve already started fantasizing about printing out real teeth and eyeballs for next year’s Halloween ghoul-fest.
A company called Invetech has created what looks to be a human tissue printer that works in a similar way to how 3D printers work. The system is capable of building up human organs cell by cell to create scaffolds that liver cells could be placed on.
Regular 3D printers use plastic that is built up layer by layer over the course of the printing session to create unique 3D objects. The new system replaces this “3D ink” with living cells so that Dr’s can print human tissue on demand.
“Scientists and engineers can use the 3D bio printers to enable placing cells of almost any type into a desired pattern in 3D,” Murphy said. “Researchers can place liver cells on a preformed scaffold, support kidney cells with a co-printed scaffold, or form adjacent layers of epithelial and stromal soft tissue that grow into a mature tooth. Ultimately the idea would be for surgeons to have tissue on demand for various uses, and the best way to do that is get a number of bio-printers into the hands of researchers and give them the ability to make three dimensional tissues on demand.”
An interesting point to make here is that the model is a production model and already delivered to a company called Organovo who in turn will supply the machines to researchers investigating human tissue repair and organ replacement.
The 3D bio-printers include an intuitive software interface that allows engineers to build a model of the tissue construct before the printer commences the physical constructions of the organs cell-by-cell using automated, laser-calibrated print heads.
“Building human organs cell-by-cell was considered science fiction not that long ago,” said Fred Davis, president of Invetech, which has offices in San Diego and Melbourne. “Through this clever combination of technology and science we have helped Organovo develop an instrument that will improve people’s lives, making the regenerative medicine that Organovo provides accessible to people around the world.”
The AICT 3D printer works with 3D data files in VRML or STL (stereolithograph) format. These files can be created with popular commercial programs like AutoCAD or Rhino3D, or with free, open-source software like Blender or Wings 3D. (AICT’s resident 3D printing technician and visualization specialist Chris Want is a volunteer developer on the Blender project.)
Using VRML or STL files as source data, the machine “prints” cross-sections of your model on a bed of plaster dust, using a sugar-water binding agent instead of ink. First, the machine spreads a thin layer of plaster, 0.004 inches thick on top of a large piston. Next, four inkjet printheads deposit the binding agent, either clear, or yellow, magenta, or cyan. Wherever the binding agent touches the plaster, the dust hardens, creating a solid cross-section of the digital model. The printer continues adding and hardening layers of dust until the model is complete.
The model is then excavated from its bed of plaster dust and gently air-cleaned. Please see the following videos to see our 3D Printer in action. The first shows the z510 laying down successive layers of plaster and binder, working towards building four of our promotional coins. The second video shows the coins after they have been removed from the machine and most of the excess powder has been brushed off. The air compressor removes the last of the powder dust.
Most commercially available rapid prototyping machines use one of six techniques. At present, trade restrictions severely limit the import/export of rapid prototyping machines, so this guide only covers systems available in the U.S.
Stereolithography
Patented in 1986, stereolithography started the rapid prototyping revolution. The technique builds three-dimensional models from liquid photosensitive polymers that solidify when exposed to ultraviolet light. As shown in the figure below, the model is built upon a platform situated just below the surface in a vat of liquid epoxy or acrylate resin. A low-power highly focused UV laser traces out the first layer, solidifying the model’s cross section while leaving excess areas liquid.
Laminated Object Manufacturing
In this technique, developed by Helisys of Torrance, CA, layers of adhesive-coated sheet material are bonded together to form a prototype. The original material consists of paper laminated with heat-activated glue and rolled up on spools. As shown in the figure below, a feeder/collector mechanism advances the sheet over the build platform, where a base has been constructed from paper and double-sided foam tape. Next, a heated roller applies pressure to bond the paper to the base. A focused laser cuts the outline of the first layer into the paper and then cross-hatches the excess area (the negative space in the prototype). Cross-hatching breaks up the extra material, making it easier to remove during post-processing. During the build, the excess material provides excellent support for overhangs and thin-walled sections. After the first layer is cut, the platform lowers out of the way and fresh material is advanced. The platform rises to slightly below the previous height, the roller bonds the second layer to the first, and the laser cuts the second layer. This process is repeated as needed to build the part, which will have a wood-like texture. Because the models are made of paper, they must be sealed and finished with paint or varnish to prevent moisture damage.
Selective Laser Sintering
Developed by Carl Deckard for his master’s thesis at the University of Texas, selective laser sintering was patented in 1989. The technique, shown in Figure 3, uses a laser beam to selectively fuse powdered materials, such as nylon, elastomer, and metal, into a solid object. Parts are built upon a platform which sits just below the surface in a bin of the heat-fusable powder. A laser traces the pattern of the first layer, sintering it together. The platform is lowered by the height of the next layer and powder is reapplied. This process continues until the part is complete. Excess powder in each layer helps to support the part during the build. SLS machines are produced by DTM of Austin, TX.
Fused Deposition Modeling
In this technique, filaments of heated thermoplastic are extruded from a tip that moves in the x-y plane. Like a baker decorating a cake, the controlled extrusion head deposits very thin beads of material onto the build platform to form the first layer. The platform is maintained at a lower temperature, so that the thermoplastic quickly hardens. After the platform lowers, the extrusion head deposits a second layer upon the first. Supports are built along the way, fastened to the part either with a second, weaker material or with a perforated junction.
Solid Ground Curing
Developed by Cubital, solid ground curing (SGC) is somewhat similar to stereolithography (SLA) in that both use ultraviolet light to selectively harden photosensitive polymers. Unlike SLA, SGC cures an entire layer at a time. Figure 5 depicts solid ground curing, which is also known as the solider process. First, photosensitive resin is sprayed on the build platform. Next, the machine develops a photomask (like a stencil) of the layer to be built. This photomask is printed on a glass plate above the build platform using an electrostatic process similar to that found in photocopiers. The mask is then exposed to UV light, which only passes through the transparent portions of the mask to selectively harden the shape of the current layer.
3-D Ink-Jet Printing
Ink-Jet Printing refers to an entire class of machines that employ ink-jet technology. The first was 3D Printing (3DP), developed at MIT and licensed to Soligen Corporation, Extrude Hone, and others. The ZCorp 3D printer, produced by Z Corporation of Burlington, MA is an example of this technology. As shown in Figure 6a, parts are built upon a platform situated in a bin full of powder material. An ink-jet printing head selectively deposits or “prints” a binder fluid to fuse the powder together in the desired areas. Unbound powder remains to support the part
