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NASA Sends DuraForm Part Into Space
 Engineers at NASA’s Jet Propulsion Laboratories
(JPL) in Pasadena, Calif.,
recently used an SLS system to produce an elaborate DuraForm® part that was launched into space. The event was part
of NASA’s Enstrophy project, a
mission that will help scientists learn more about the Aurora Borealis (Northern Lights).
The DuraForm part is an elaborate “science cup.” This tray-like fixture holds a
variety of instruments, wiring and batteries within a hockey puck-sized, selfcontained
spacecraft called the Free Flying Magnetometer (FFM).
NASA recently launched four FFMs into an auroral event in the upper atmosphere.
The units ejected from a rocket and fell back to earth, all the while measuring
minute variations in the aurora’s magnetic fields. According to scientists
at NASA and the University of New Hampshire (UNH), such magnetic variations
may be the cause of these ethereal winter light shows.
Finding the right process and materials
As NASA prepared for its Enstrophy mission, it faced several challenges in producing the
science cups. First, it had to find a way to fit many instruments into a very small device. Second, it hoped
to create the part fairly quickly. Finally, it needed to create the parts using a material that was sturdy
enough to endure the jarring vibrations of launch and the extremes of the upper atmosphere
without creating any magnetic or electrical interference.
“Typically, we machine parts like these out of aluminum, steel or titanium,” says Kobie
Boykins, member of the Mechanical Engineering Section at JPL. “Unfortunately, this design had thin walls
and tiny, complex features, that ruled out both metals and machining. It would have been very
difficult and exorbitantly expensive to create this part that way.”
“These pieces held up well to all kinds of abuse, handling and machining.”
Kobie Boykins, Jet Propulsion Laboratories
Just how expensive? Boykins estimates it would have cost between $3,000 and $5,000 to
fabricate the parts using machining and other traditional methods. Knowing that, Boykins and his colleagues
at NASA explored other options, including CNC and EDM, and made careful note of the
materials used.
Based on NASA’s research, it gave the SLS process the best chance of meeting the
required strength and resolution tolerances. Upon testing the DuraForm parts, NASA’s strength calculations
proved to be achievable—and the parts were prepared for launch.
“From what we could tell, these pieces held up well to all kinds of abuse, handling, and
machining,” Boykins notes. “We also didn’t notice any dimensional changes.”
Comparing the cost of producing the science cups via traditional methods versus that of the SLS
process, Boykins notes that the DuraForm parts cost only about $300. That’s one-tenth the estimated
cost of using traditional methods, such as machining.
Other benefits
“What’s nice about the SLS parts is we could make small changes very rapidly, with
machining or sanding, or by simply changing the CAD file and generating another set of
SLS parts,” Boykins says. “This accommodated our needs when we wanted to add new features as the project progressed. It was extremely beneficial to us.”
Just how many iterations did NASA go through? Boykins says he produced four SLS parts
and more than 30 manual modifications to these parts. “It was no big deal,” he says.
Boykins also notes that having SLS parts to show the engineers and technicians involved
“was worth its weight in gold. We could go up to the technician who was wiring up the FFM
and ask about features, spacing and so on. This really helped us with communicating
about the project. It would’ve been far more tedious had we not used the SLS process.”
The final product
NASA sent four FFMs into space, each outfitted with a DuraForm science cup holding more
than six instruments, including laser beacons, sun sensors, a magnetometer, batteries, a transmitter and an antenna.
All instruments, except the batteries, were glued into the science cups using a
space-approved epoxy glue. These elements formed an assembly that slid into a graphite
epoxy shell that was screwed together to form a protective case.
“Our scientists and principle investigators at JPL and UNH are very happy with the results,”
Boykins says. “They are excited about the SLS technology and how we can use it to
produce small, self-contained spacecraft. The opportunities here are immense and could include missions to other planetary bodies.”
Boykins adds, “In the future, as SLS materials get stronger, as we go through the
exhaustive testing to qualify them for extended space use, and as we find more uses for
this kind of technology, it will drastically reduce our time-to-fabrication
and increase the numbers and types of iterations we can afford to do. It’s limitless as to what can happen then.”
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