Monday, April 18, 2011

Rapid Prototypers, 3D Printers: an Exciting Invention

Rapid prototyping technology can best be explained as the latest development in the history of modern manufacturing. “Industrialization marked a shift to powered, special-purpose machinery, factories and mass production. The iron and textile industries, along with the development of the steam engine, played central roles in the Industrial Revolution, which also saw improved systems of transportation, communication and banking.” (History.com, n.d.) Until the industrial revolution in the 1700’s, most goods were hand crafted by artisans who worked on each piece one at a time by hand. This resulted in work that was detailed, but extremely time consuming to create. Eli Whitney is commonly attributed with the invention of interchangeable parts. While this attribution is not entirely accurate, the practice of interchangeable parts introduced the concept of design tolerance. Henry Ford introduced the production line to build his Model T cars at a price that the common person could afford, including his own employees. Production lines efficiencies were improved with the introduction of robotic controls and machinery. CNC machines were created to mill out complex parts out of solid blocks of material such as aluminium. They use a computer to guide the drill, allowing complex shapes to be accurately made repeatedly. Finally, rapid prototypers were invented to be able to create new designs quickly and accurately in house. Instead of emailing a design to a manufacturer and getting the part mailed back a week or a month later, the engineer can literally create a new design and print it out in hours – reducing the innovation cycle time from weeks to hours.
There are a range of Rapid prototypers that utilize a range of printing techniques that depend on the type of material being used and the use of the design. Laser Sintering, annealed powder, photo-resist, and thermoplastic deposition are some main categories, and new types are being developed, such as cell placement for replacement organ printing. Laser sinter machines build by laying down a layer of metal powder and firing a high powered laser at the fine metal grains. This melts and fuses them together layer by layer to create a solid metal object. Annealed powder uses a similar technique only using plastic powder to make each layer and a binder to solidify the powder. The photo-resist method uses a bath of special liquid that hardens when exposed to light to build. Either lasers or a projector can be used to develop the liquid material into solid. The finished project is removed from the bath and allowed to drain, then cured. Thermoplastic deposition is similar to our familiar inkjet printers, except that it melts plastic wire and deposits it on a platter instead of ink on paper. Of recent note there is an experimental design that places living cells in a matrix that may allow us to print out replacement organs in the future. “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,” says Keith Murphy, CEO of Organovo. (Quick, 2009) Currently, only simple veins and arteries have been able to be printed in this manner but the technique shows incredible promise for those needing organ transplants. If ever adult stem cell technology is developed, these technologies together could build replacement organs for patients with no risk of rejection.
Rapid prototypers were originally prohibitively expensive, costing well over $100,000. The high costs limited their use to large corporations and production houses that catered to engineers and architects. “Three-dimensional printing makes it as cheap to create single items as it is to produce thousands and thus undermines economies of scale. It may have as profound an impact on the world as the coming of the factory did....Just as nobody could have predicted the impact of the steam engine in 1750—or the printing press in 1450, or the transistor in 1950—it is impossible to foresee the long-term impact of 3D printing. But the technology is coming, and it is likely to disrupt every field it touches. ... A basic 3D printer, also known as a fabricator or “fabber”, now costs less than a laser printer did in 1985.” (The Economist, 2011) This technology has improved in several ways. Price drops have allowed it to be bought and used by more companies, small businesses, and even avid hobbyists. Currently, the base model price for a professional 3D printer is less than $15,000 from one major manufacturer. For do-it-yourselfers, the RepRap and MakerBot community provide plans and kits to make your own for around $500. “RepRap is a free desktop 3D printer capable of printing plastic objects. Since many parts of RepRap are made from plastic and RepRap can print those parts, RepRap is a self-replicating machine - one that anyone can build given time and materials. It also means that - if you've got a RepRap - you can print lots of useful stuff, and you can print another RepRap for a friend...” (RepRap, 2011) One exciting facet about the DIY approach is that as innovators develop upgrades, the printer can print out many of its own upgrades and replacement parts. Innovations in print heads and stepper controls have resulted in printers with increased resolution. These new printers can make parts with finer detail. Also, engineers and innovators are experimenting to develop printers that can use more materials, from aluminium, steel, plastic, rubber, photo-resist, and even living cells. Newer models even have multiple heads, to print in multiple colours and different materials in the same object. These improvements and cost reductions have allowed 3D printers to expand into new markets and create new businesses. One such business is making custom prosthetics for amputees. Scott Summitt, founder and CTO of Bespoke Innovations writes in one article, “Since this process has gone live, amputees have returned with requests for more parts. More chrome parts, more tattoos, wood accents, debossed text-all is fair game when the process is entirely digital. But like the person who wears it, each fairing is unique in every way. In fact, like nature, the process is fundamentally unable to create anything but unique parts. To us, this thinking treats people who come to us with respect, allowing them to showcase their unique form and treat it as the dynamic sculpture that is the human body. We hope to change their interactions with strangers, replacing the awkward stares with inspired grins, removing some of the discomfort and alienation that many face each day.” (Summitt, 2011) Projects like Summitt’s show the potential to do more than introduce a new gadget into our lives. This application can do much to improve the quality of life for amputees, helping them regain confidence and self esteem.
The future of these prototypers is exciting even when excluding the prospect of further development. “What determines a civilization’s ability to move forward? In large measure, it is mastery over materials. The key indicators of progress— military prowess; the ability to produce goods; advances in transportation, agriculture, and the arts—all reflect the degree to which humans have been able to work with materials and put them to productive use.” (National Science Foundation, n.d.) However, there is a dark side to this, as with any technology. The unscrupulous and unethical may, and indeed probably will, use this technology for evil. While art enthusiasts may look forward to replica paintings – authentic down to the brushstroke! – art dealers will have to prepare for clever frauds. I can easily imagine shops that don’t need to keep inventories. An auto repair shop can easily print out many types of replacement parts from an online catalog so they don’t have to wait for a distributer cap, for one example. However, projectile weapons may someday be able to be printed on demand as well. Manufacturers use mostly man made materials to make shoes, so it is no stretch of the imagination to see boutique shops printing customized footwear for their customers. Mass production is not a prototyper’s forte. Mass customization is the strength and the weakness of prototypers: while they allow for rapid adjustments to structure, form and function of the finished part, there can be no replacement for quality design. When a single manufacturer produces a million pairs of shoes, they can control the quality in house. When a thousand boutique manufacturers can make custom shoes (or any other parts) on the fly, quality of design will vary greatly from one company to the next. If the customer’s shoes fall apart the second day of wearing, they will be understandably upset. If the customer’s car falls apart on the freeway, they will be understandably dead.
One final concern is of a legal nature. One accessory to rapid prototypers is the 3D scanner. 3D scanners work by taking images of an object placed on a rotating base and stitching those scanned images together into a virtual object. This virtual object can then be printed out using a rapid prototyper. While this can be useful in legal applications, like making a scaled or even a life sized bust of yourself – and who wouldn’t want one of those in their library? – it very easily can copy designs that were invented by another. The media is full of stories about the fight between music labels and file sharers. Think then, if this were extended to everything you own. Is your chair authentic? What about your toaster? We have cheap knockoff handbags and clothes that are copies of luxury brands. Soon, you may be able to get cheaply printed jewelry, furniture, and even car parts. While knockoff consumer electronics may cause the inventor to lose revenue, a poorly printed safety device could result in loss of limb or life if it were to fail. Clearly, a set of guidelines that details the limitations of printed parts would be useful, if only as a guide for the purchaser in regards to caveat emptor.
Innovations are limited by the imagination of the inventor, and the tools and raw materials available. As our understanding of materials sciences improves, so does our ability to manipulate the elements around us. Stores today offer devices that would be worth millions just a few decades ago, and they are sold as cheap disposable toys! (Miniature R/C helicopter, anyone?) The end goal of rapid prototype technology is the holy grail of manufacturing: molecular assembly. One of the few hard science fiction concepts that have yet to be attained is the ability to build atom by atom. With this technology, it may be possible to actually copy a live person, with his memory and personality intact. This presents an even bigger conundrum than cloning. Cloning will result in an individual with identical DNA as the host, but with their own memories and personality. If our memories are molecular in nature an atomic copy will result in two individuals with identical memories as well. If you copy the CEO of a corporation, who does his job? How do you prosecute a murderer if he has a copy and you cannot tell which one did the deed? Finally, if one could copy himself, what are the ethical responsibilities to the copy? If a person copies themselves, then kills the copy, is it murder – or suicide? The positives of this technology will, I am sure, outweigh the risks, however. In the future we will be able to assemble exotic chimeras of materials that can be made no other way. Molecular assemblers could be used to construct a space elevator, or replacement organs and limbs. The standards of quality will have a paradigm shift. No longer will we accept something that is off by millimeters when we can get it accurate to the atom. How this will help us as a society is a question that can only be answered by the people that make up our civilization. Our humanity will be the defining author when whatever we imagine can be realized in fact. Let us hope that kindness, charity, and compassion define our humanity.

Works Cited
History.com. (n.d.). Industrial Revolution. Retrieved April 11, 2011, from History: http://www.history.com/topics/industrial-revolution
National Science Foundation. (n.d.). Advanced Materials. Retrieved April 12, 2011, from nsf.gov: http://www.nsf.gov/about/history/nsf0050/pdf/materials.pdf
Quick, D. (2009, December 15). 3D Bio-printer to create arteries and organs. Retrieved April 11, 2011, from gizmag.com: http://www.gizmag.com/3d-bio-printer/13609/
RepRap. (2011, February 19). Main Page. Retrieved April 13, 2011, from RepRap Wiki: http://reprap.org/wiki/Main_Page
Summitt, S. (2011, January 5). Because One Size Doesn't Fit All: Using RTAM to Profoundly Enhance Prosthetics. Retrieved April 14, 2011, from Time Compression: http://www.timecompression.com/articles/because-one-size-doesnt-fit-all-using-rtam-to-profoundly-enhance-prosthetics
The Economist. (2011, February 10). Print me a Stradivarius. Retrieved April 13, 2011, from The Economist: http://www.economist.com/node/18114327?story_id=18114327