Reimagining satellite - spacecraft with metal parts made on 3-D printers. Someday, those additively manufactured parts might be assembled into ...
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Satellite manufacturers are beginning to equip
spacecraft with metal parts made on 3-D printers.
Someday, those additively manufactured parts
might be assembled into spacecraft largely by robots
operating in clean rooms. Debra Werner looks at
the coming satellite manufacturing revolution.
Reimagining satellite
L
ockheed Martin’s booth at the annual additive processes, but joining them to-
Defense Manufacturing Conference in gether into a functioning spacecraft, called
San Antonio was a popular stop for integration in industry parlance, is still
the curious. Inside a plexiglass box, a done almost entirely by hand. It is as
6-foot-tall orange robotic arm deposited though a great sculpture slowly takes
tiny beads of a carbon fiber-reinforced shape, and indeed, even commercial com-
polymer a layer at a time. Within minutes, a munications satellites — among the fastest to
satellite model the size of a small refrigera- build — take two to three years to complete.
tor began to take shape, although the whole Lockheed insists that an entirely new
process took hours. A second robot carved approach is no longer a far off dream. The
away excess material and used a laser revolution will start with the frame and
tracker to inspect its work and verify the subsystems including power propulsion
dimensions of the final product. and communications gear, collectively
This is how Lockheed engineers think called the bus.
they will eventually build satellites: by “Our goal is to print an entire satellite
marrying additive manufacturing with ro- bus with additive manufacturing in the next
botics. That would be a radical departure four years, and we may accelerate that
from today’s processes, which go some- goal,” says materials engineer Slade Gard-
thing like this: ner, a Lockheed Martin fellow focused on
Engineers and technicians in clean advanced manufacturing and materials.
suits typically receive structures made by Lockheed Martin engineers don’t plan
vendors or subcontractors in far-off facto- to build a satellite’s advanced optics or
ries or in house. A small but increasing electronics on additive machines, but they
by Debra Werner fraction of those parts are today made by do envision a turntable surrounded by ro-
20 AEROSPACE AMERICA/MARCH 2015 Copyright 2015 by the American Institute of Aeronautics and Astronautics
construction
Robotic arms build a satellite
model at the Lockheed Martin
booth at the the Defense
Manufacturing Conference
in San Antonio.
Lockheed Martin
bots working together to build a light- spacecraft can be built through additive pro-
weight spacecraft bus embedded with cesses, and someday with robotics. The pay-
many of its subsystems including propul- off for manufacturers could be an edge in
sion and antennas. the lucrative but crowded market for con-
“Where it makes sense, a human will struction of communications satellites, spy
install payload elements and cabling,” satellites and scientific spacecraft.
Gardner says. Time is money, and building a satellite
Lockheed is not alone in seeing this po- faster is one way to reduce costs and win a
tential. Satellite manufacturers including competition. Trimming component weight
Space Systems/Loral of Palo Alto, California, through additive processes could also let
are vying to convince customers that reliable engineers pack more equipment on a satel-
AEROSPACE AMERICA/MARCH 2015 21
Space Systems/Loral produced a 3-D
printed titanium antenna bracket, at
left, that has half the mass of
its 0.4-kilogram conventionally
machined titanium counterpart.
A computer-aided design
optimization process minimizes the
material needed to meet strength
and stiffness requirements.
Space Systems/Loral
lite or alternatively a customer could reduce Moving cautiously
the spacecraft’s overall mass to reduce Although 3-D printing promises savings,
launch costs, given that rocket providers satellite builders are proceeding cautiously
charge customers partly by the weight of as they move additively manufactured
their spacecraft. parts from their ground-based applications
Part of the mass of a conventional into space. NASA’s Juno mission, which
component comes from limitations in the launched in 2011 on its way to a 2016 ren-
dexterity of the machining tools, limita- dezvous with Jupiter, carried the first ones:
tions in the details that can be cast in a four sets of waveguide brackets printed
mold, and the need to make multiple parts using electron beam melting, an additive
and assemble them. Some material is de- process that turned a powdered titanium
signed not for strength or insulation, but alloy into the finished product. That suc-
simply because of manufacturing con- cess prompted Juno prime contractor
straints or to provide surfaces to join parts Lockheed Martin to expand its use of ad-
together. Additive manufacturing could re- ditive manufacturing and to install equip-
duce parts counts and lead to streamlined ment used in 3-D printing of polymers and
components. metals in its factories in Colorado, Califor-
“As we start to permeate this technol- nia, Louisiana and Mississippi.
ogy through the satellite, we can take out 15 Additive parts are happening now, but
percent of the mass in most cases and often a shift to robotics is expected to take lon-
50 percent,” says Derek Edinger, director of ger, because each satellite is different and
advanced materials and structural technol- requires painstaking assembly. Vendors
ogy for Space Systems/Loral, a subsidiary of such as MDA and Wolf Robotics are work-
Richmond, British Columbia-based MDA ing to perfect robots for satellite assembly.
Corp. and one of the world’s largest manu- Space Systems/Loral is preparing to
facturers of commercial communications send its first titanium parts created through
satellites. “That is the real draw for our cus- additive manufacturing into space later this
tomers, because reduced satellite mass year and to include 3-D printed metal parts
means more room for radio frequency pay- on almost all subsequent satellites. The
loads, which generate revenue, and more first parts destined for space are identical
fuel to extend the satellite’s life.” fittings that go on each end of the struts
that crisscross a satellite’s interior. Although
22 AEROSPACE AMERICA/MARCH 2015
the fittings do not look very complex, the a company based in Chicago that special-
simple fact that manufacturers are trusting izes in electron beam welding and additive
additive manufacturing to build load-bear- manufacturing, to build a large propellant
ing elements of a spacecraft is significant tank simulator for a new satellite design.
because satellite customers are notoriously Lockheed Martin tested the tank at its max-
risk-averse. Space Systems/Loral can’t yet imum expected operating pressure on 50
reveal publicly which satellite will carry separate occasions and then subjected it to
the parts, but executives confirm that they pressure levels 25 percent beyond that an-
are destined for a communications satellite ticipated maximum pressure 12 more times.
slated for launch into geostationary orbit in Finally, Lockheed Martin conducted de-
late 2015. structive testing, adding pressure until the
Commercial communications satellites tank burst, which occurred at more than
cost hundreds of millions of dollars to twice its anticipated maximum pressure.
build and launch. To become profitable, “Customers love to see data because it
satellite operators need their spacecraft to builds confidence,” Gardner said.
remain healthy for more than a decade in
an environment where temperature ex- Saving time, money and weight
tremes and punishing radiation are the Satellite customers are eager to realize the
norm. Satellite customers typically want potential savings additive manufacturing
manufacturers to use only flight-proven promises. In general, it cuts the cost of pro-
parts on their spacecraft, says David Bern- ducing metal components in half and re-
stein, Space Systems/Loral senior vice duces the time it takes to build them by 80
president of program management. percent, Gardner says.
To reduce the risk inherent in introduc- In many cases, companies can save
ing any new satellite components, manufac- time and money because additive manufac-
turers conduct extensive testing. Last year, turing allows them to print complex de-
Lockheed Martin worked with Sciaky Inc., signs that marry several individual compo-
European Space Agency
Thales Alenia Space used a 3-D printer to produce a prototype deployment mechanism for satellite solar panels.
The titanium device has fewer parts and about one-fifth the mass of a similar, conventionally produced mechanism,
according to the European Space Agency.
AEROSPACE AMERICA/MARCH 2015 23
nents into a single unit. Reducing the total facturers have used 3-D printed parts in
number of parts leads to cost, schedule and their ground-based operations. Space Sys-
weight reductions. “Fewer parts mean less tems/Loral uses 3-D printers to turn plas-
material, fewer assembly operations and tic polymers into the type of complex tools
fewer part numbers,” Gardner said. “Each and fixtures engineers need for various
part number requires engineering attention, jobs, such as holding spacecraft parts in
testing and quality inspection.” place until they can be bolted down or
Over the last decade, satellite manu- serving as a stand-in for a component not
Lockheed Martin engineers work
on a Space-Based Infrared System
satellite. In the near future, experts
say, 3-D printing and robotics will
reduce the number of people and
the amount of time needed to build
satellites.
Lockheed Martin
24 AEROSPACE AMERICA/MARCH 2015yet built. With the temporary parts in
place, workers can lay out wiring and per-
form other assembly tasks without waiting
for the finished parts.
Before 3-D printing, manufacturers
built the same types of custom tools and
fixtures on machines using aluminum. That
process often took months. Their replace-
ments can be designed in a week and
printed in a couple of days.
“This is the unsung hero of additive
manufacturing,” Edinger says. “In addition
to cost and schedule savings, it has en-
abled us to make much more complicated
satellites.”
Space System/Loral’s Ka-band data sat-
ellites, for example, which use powerful
beams to broadcast communications to
small antennas on Earth, carry radio fre-
quency payloads composed of thousands
of parts. That level of complexity would not Stratasys’ 3-D printers can produce objects in a variety of Stratasys
have been possible without 3-D printing materials, including ULTEM 9085, a thermoplastic the company
and other sophisticated manufacturing uses to print antenna supports for Formosat-7 satellites.
tools, Edinger says.
Within the last year, Space Systems/
Loral also began using 3-D printers to weather forecasts. GPS radio occultation
produce lightweight brackets and thermo- systems measure the refraction of GPS sig-
plastic shields to protect motors and opti- nals traveling through the atmosphere to
cal lenses. obtain information on temperature and wa-
“We can make complex parts more ter vapor. Clusters of Taiwanese Formosat-7
quickly and inexpensively than we did spacecraft — six to be launched in 2016 and
with machined aluminum or fiberglass,” six in 2018 — will carry U.S. supplied COS-
Edinger says. MIC-2 instruments, short for Constellation
Engineers use software tools to deter- Observing System for Meteorology, Iono-
mine the desired characteristics of the new sphere and Climate-2. The satellites will be
parts, including the forces they will need to built with “the first additively manufactured
withstand. Then the engineers design the parts on the outside of a spacecraft,” says
components to withstand those forces in a Jim Bartel, Stratasys senior vice president
compact, lightweight form. for direct manufacturing.
Now that printed parts are beginning Stratasys is building the supports,
to move from the factory floor to satellites, which will be used to attach two phased
manufacturers and suppliers expect their array antennas to each one of the 12 satel-
use and complexity to grow rapidly. lites, using a strong thermoplastic called
“We haven’t even scratched the surface ULTEM 9085 that is similar in strength to
of where we will be two to five years from metal but weighs less. The same material is
now,” says Joel Smith, strategic account used in commercial aircraft and approved
manager for aerospace and defense at by the FAA because it meets the agency’s
Stratasys Direct Manufacturing of Minneap- flame, smoke and toxicity requirements.
olis, which makes 3-D printers and produc- NASA plans to coat the 3-D printed parts
tion systems. with a paint designed to shield them from
In November, Stratasys began working ultraviolet radiation.
with NASA’s Jet Propulsion Laboratory to The mission is technically daring, with
print 30 antenna supports for a joint a potentially large payoff, says Bartel: “If
U.S.-Taiwan satellite project designed to use we can make parts that hold up on the out-
GPS radio occultation systems on forthcom- side of a spacecraft, we can make parts that
ing clusters of small satellites to improve go pretty much anywhere else.”
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