Making a gun with a printer is old news. The latest applications under development are straight from science fiction: ready-to-fly drones, transplantable organs, ammunition and even meals.
Three-dimensional printing burst into the collective consciousness almost overnight with revelations that a Texas group fired a printed plastic handgun in May and put the plans on the Internet. But the U.S. government -- from NASA to the Navy -- has been using and studying the technology for more than a decade, and the possibilities are limited only by imagination.
The Navy is at the forefront of Defense Department efforts because it often operates remotely, relies on an expensive supply network, and has limited space on ships for supplies. Navy officials believe the technology could have a huge impact on maritime strategy.
"It's an evolving technology, but I think it has incredible potential," Navy Lt. Cmdr. Michael Llenza, senior naval fellow at the Atlantic Council's Brent Scowcroft Center on International Security, told Stars and Stripes. "I see it as an enabler for sea placing because it can cut down on the lengthy and costly supply chain."
Llenza has been studying 3-D printing over the course of his fellowship, enticed by the technology after personally seeing how one broken part could hold an aircraft back from a combat mission and affect military readiness.
The naval flight officer is slated to give a report to the Navy upon the completion of his work. In May, he wrote an article in the Armed Forces Journal that offered a window into U.S. government and academic efforts that go far beyond a one-shot plastic handgun.
Three-dimensional printing -- also known as additive manufacturing -- is the process of inputting specifications for a three-dimensional object into Computer Aided Drafting software and using a printer to create it from a chosen material. Most current printers work with a single material, like plastic or metal, but multi-material printers are in the early stages of development. Printers can cost several hundred dollars to more than $500,000.
The Walter Reed National Military Medical Center and its predecessor have been using 3-D printing since the mid-1990s, according to Navy Capt. Gerald Grant. The Army began pouring resources into 3-D printing as the wars in Afghanistan and Iraq raged and wounded troops came back with amputations as well as facial and cranial injuries. Now, their 3-D Medical Applications Center encompasses an entire floor and features some of the best 3-D printing equipment in the Defense Department.
The center has the capability to scan a servicemember's wound and produce everything from custom titanium cranial plates to custom prosthetics that used to be fabricated by hand and almost always had to be whittled down because the fit wasn't quite right.
"It's changed medicine," Grant said. "Now we sit around and ask, ‘What do we want these pieces to do?' instead of ‘What kinds of pieces can companies build?'"
All three Naval Air Systems Command Level III Depots -- Naval Air Station North Island, Calif.; Marine Corps Air Station Cherry Point, N.C.; and Naval Air Station Jacksonville, Fla. -- use 3-D printers to make tools, models and parts. There are 83 plastic parts that can be made for the F/A-18 and more than 300 for the Joint Strike Fighter, according to spokesman Gary Younger.
At the Naval Sea Systems Command, 3-D printers are developing large, complex, epoxy resin ship models for hull-form testing, streamlining technology development, said spokesman Chris Johnson. The command's Naval Surface Warfare Center makes parts for weapons systems to see whether they fit. If they do, the specifications are used to make the more expensive and time-consuming hardened steel parts.
Last year, the Naval Undersea Warfare Center in Keyport, Wash., acquired a printer that can produce parts made from high-strength polycarbonates and high-temperature plastics for ships and submarines; make large structural components for autonomous vehicles and large fixtures for manufacturing tooling; and form dies for aircraft components.
The Naval Air Warfare Center Weapons Division in China Lake, Calif., uses 3-D printing to make test and prototype parts as well as tools for unmanned aerial vehicles and the F/A-18, according to Nevin Hill, mechanical engineer at Applied Manufacturing Technology Division.
"For the Navy, the technology promises to shift inventory from the physical world to the digital one," Llenza wrote. "Instead of actual parts, a ship might carry 3-D printers and bags of various powdered ingredients, and simply download the design files needed to print items as necessary."
Llenza said Military Sealift Command ships might even be converted into floating factories that take orders for the battlegroup. However, pumping out critical parts and sticking them directly into a plane or naval vessel won't happen in the near future, due to U.S. military certification standards.
Tanks, organs and food
The private sector and academic community have also embraced 3-D printing and research. Several collegiate laboratories and at least one defense contractor have pumped out a UAV comprised entirely of printed parts -- except for the motor and electronics, Llenza said. He said printing them with functioning systems in place is the goal, and it may not be that far off.
Researchers from the University of Southern California have developed a system for building shelters or other structures on a beachhead or forward operating base, called the Contour Crafting system, Llenza said. The system is essentially a printer head that moves on rails and uses special cement from a tank or truck. It can build a 2,500-square-foot structure -- with walls three times the strength of ordinary construction -- in about 20 hours. They have also developed a system that can print glass objects from desert sand.
A San Diego company called Organovo specializes in bio-printing functional human tissue, according to its website. Llenza said it has re-created lung and heart tissue, cartilage and bone. Implantable organs might be next.
Researchers from Virginia Tech's 3-D printing labs told Llenza that using 3-D printers to produce ammunition is worth exploring. Making the casing would be relatively easy. The hard part would be in finding a way to print the "energetic component," Llenza said.
NASA has plans to put a printer on the International Space Station next year, spokesman David Steitz said. It also is exploring making spacecraft and rocket parts, producing construction materials from lunar dust and using protein powder to make food for long space flights.
Llenza said muscle cells are extracted from a cow or a pig, allowed to multiply and inserted into cartridges as bio-ink. The printer lays down the cells, and it develops into muscle. It can then be shaped, cooked and flavored.
"All of the requirements for this process exist aboard a carrier or a submarine; all you would need to add is the machinery and the ‘ink,' which in this case is bags of powder," Llenza wrote in his article. "Printed food, while admittedly not a terribly appealing concept, can shorten the Navy's logistical tail, reducing security risks, costs and energy consumption."
A powerful technology, not without risk
Interest in the technology is global. China claims it is printing aircraft parts and putting them directly into J-15 fighters, Llenza said. Singapore just sank $500 million into its own 3-D printing program.
"There are a lot of countries pouring a lot of money into this," Llenza said.
The new technology also brings new risks, Llenza said. Critical parts would no longer sit on shelves; they would lay dormant in computer files, susceptible to hacking and sabotage. Safety checks and standards would have to be developed to ensure the quality of 3-D printed parts before use in critical systems like ships and aircraft.
"If your enemy can steal and create files for proprietary designs, what's to stop him from hacking into your system and modifying them?" Llenza wrote. "Suddenly, your printed UAVs are mysteriously collapsing upon launch. Or your bio-printed kidney fails. Or your printed vaccine, tested as safe and effective, proves otherwise."
Llenza also warns that multi-material printers could be used to make the next generation of improvised explosive devices, such as a workable fire hydrant.
Llenza said the rewards are worth the risks.
"Even in today's infant state, it's easy to see how 3-D printing might drastically enhance our naval capabilities," Llenza wrote. "A capability that increases our autonomy and grants us an organic ability to produce those items that keep us operational and in the fight as long as possible will have a huge strategic impact on the service."