The US Navy Analysis Lab develops practical, light-weight, cylindrical 3D printed antenna arrays
Engineers at the US Navy Research Laboratory (NRL) used a 3D printer to create optimized antenna components that could be critical to the advancement of the US Navy’s radar surveillance capabilities.
With the help of 3D printing, engineers have been able to create cylindrical arrays at a lower cost and with shorter lead times than traditional specialty equipment. The resulting parts also turned out to be significantly lighter than previous iterations, potentially giving them new navigation or defense applications for end use.
“With 3D printing, rapid prototypes can be made and multiple design iterations can be performed very quickly and at minimal cost,” said NRL electrical engineer Anna Stumme. “The low weight of the printed parts also enables us to use the technology for new applications where the heavy weight of the solid metal parts restrict us.”
Engineer Anna Stumme and her NRL colleagues have 3D printed optimized cylindrical arrays (illustration). Photo via the NRL.
Maintenance of marine antenna arrays
While deployed at sea, naval vessels rely heavily on their radars, not only as a means of maritime navigation but also to remotely monitor the movements of potential attackers. These critical systems are fed by arrays made up of interconnected antennas. However, they can often break, requiring a quick replacement.
At present, such emergency solution parts are either ordered made of metal or laboriously machined, which can take weeks. On the other hand, Stumme and her NRL colleagues found, using a 3D printer, that components like cylindrical arrays can be made in a matter of hours due to the shorter machining and assembly time.
While foreign defense forces like the Dutch Navy have introduced INTAMSYS 3D printing to produce spare parts as needed, the NRL does not yet consider this realistic. In fact, the engineers claim that the technology has greater potential for rapid iteration of new designs, which they have put to good use with their novel antenna array.
“We’re not trying to say that we have to 3D print everything and put it on a ship because that’s not realistic,” said Stumme. “We don’t necessarily know how things would hold up in this environment. For us, this is a way to test more design iterations in a short amount of time. “
The 3D printed cylindrical array (picture above) turned out to be more compact than the original (picture center). Photo via the NRL.
3D printing of the NRL antennas
After winning an award for their initial research at the Antenna Applications Symposium 2019, the NRL team explored how 3D printing could be used to optimize the weight of related parts. First, engineers made a number of nylon prototypes before electroplating them in the lab’s Autonomous Systems Research facility.
During the process, the researchers were able to add a thin layer of metal to each part, giving them the conductive surface necessary to route applications. Once completed, the prototypes were subjected to surface roughness characterization tests that enabled the team to effectively assess the impact of the exterior coating on their performance.
“Surface roughness is important for waveguides and antennas as it can cause scattering losses and result in a less efficient antenna,” said Nick Charipar, Head of Applied Materials and Systems. “Antennas radiate and receive waves. So when a wave is traveling along a rough surface, it is distorted and the energy may not go where you want it to go. “
After the initial tests, the NRL’s radar department installed the components to see how they would affect radar functionality. In doing so, she found that the characteristics of each 3D printer affected the performance of the device. As a result, the team concluded that if an optimized set of parameters can be identified, replacement arrays can be manufactured quickly anywhere in the world.
Later this year, Stumme and the NRL crew intend to conclude their study with a field test of a prototype cylindrical array aperture that will be incorporated into an X-band surveillance radar. The arrays that give small ships 360 ° visibility are 3D printed using lightweight optical fibers, which may give them improved thermal performance.
The US Navy and pressure at sea
The US Navy has long recognized the potential of 3D printed parts and has invested heavily in their research and end use.
Most recently, the US Naval Postgraduate School (NPS) was the first to install the new ElemX Liquid Metal 3D printer from Xerox. The NPS has effectively partnered with Xerox to develop new ways to manufacture parts that will be made available for use by the U.S. Forces when needed.
The Naval Sea Systems Command (NAVSEA) division of the U.S. Navy has also funded seven R&D programs that could achieve cost savings of $ 250 million. With an initial cost of only $ 8.2 million, the partial optimization initiatives may be a highly efficient way to reduce maintenance on board naval vessels.
Elsewhere, scientists at the Naval Surface Warfare Center have developed and patented a novel biodegradable 3D printing material. The team believes that the new polymer could be used in the future to manufacture underwater equipment such as unmanned or autonomous underwater vehicles (UUVs).
Don’t forget to subscribe to the 3D printing industry newsletter or follow us on Twitter or like our page on Facebook to keep up to date with the latest 3D printing news.
Are you looking for a job in the additive manufacturing industry? Visit 3D Print Jobs for a selection of roles in the industry.
The picture shown shows Anna Stumme making adjustments to an antenna array in the anechoic chamber of the NRL. Photo via the NRL.