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NASA’S PERSEVERANCE ROVER BRINGING 3D-PRINTED METAL PARTS TO MARS
If you want to see science fiction at work, visit a near by machine shop, where 3D printers create materials in just about any shape you can imagine.
NASA is exploring the technique – known as additive manufacturing when used by specialized engineers
– to build rocket engines as
well as potential outposts on the Moon and Mars. Nearer in the future is
a different milestone: NASA’s Perseverance rover, which lands on
the Red Planet on Feb. 18, 2021, carries 11 metal parts made with 3D printing.
Instead of forging,
molding, or cutting
materials, 3D printing
relies on lasers to melt
powder in successive
layers to give shape to
something. Doing so allows
engineers to play with unique
designs and traits, such as making hardware lighter, stronger, or responsive to heat or cold.
“It’s like working with papier-mâché,” said Andre Pate, the group lead for additive manufacturing at NASA’s Jet Propulsion Laboratory in Southern California. “You build each feature layer by layer, and soon you have a detailed part.”
Curiosity, Perseverance’s predecessor, was the first mission to take 3D printing to the Red Planet. It landed in 2012 with a 3D-printed ceramic part inside the rover’s ovenlike Sample Analysis at Mars (SAM) instrument. NASA has since continued to test 3D printing for use in spacecraft to make sure the reliability of the parts is well understood.
As “secondary structures,” Perseverance’s printed parts wouldn’t jeopardize the mission if they didn’t work as planned, but as Pate said, “Flying these parts to Mars
is a huge milestone that opens the door a little more for additive manufacturing in the space industry.”
A Shell for PIXL
Of the 11 printed parts going to Mars, five are in Perseverance’s PIXL instrument. Short for the Planetary Instrument for X-ray Lithochemistry, the lunchbox-size device will help the rover seek out signs of fossilized microbial life by shooting X-ray beams at rock surfaces to
analyze them.
PIXL shares space with other
tools in the 88-pound (40-kilogram) rotating turret at the end of the rover’s 7-foot-long (2-meter- long) robotic arm. To make the instrument as light as possible, the
JPL team designed PIXL’s two-piece titanium shell, a mounting frame, and two support struts that secure the shell to the end of the arm to be hollow and extremely thin. In fact, the parts, which were 3D printed by a vendor called Carpenter Additive, have three or four times less mass than if
they’d been produced conventionally.
“In a very real sense, 3D printing made this instrument
possible,” said Michael Schein, PIXL’s lead mechanical engineer at JPL. “These techniques allowed us to achieve a low mass and high-precision pointing that could not be made with conventional fabrication.”
MOXIE Turns Up the Heat
Perseverance’s six other 3D-printed parts can be found in an instrument called the Mars Oxygen In-Situ Resource Utilization Experiment, or MOXIE. This device will test technology that, in the future, could produce industrial quantities of oxygen to create rocket propellant on Mars, helping astronauts launch back to Earth.
To create oxygen, MOXIE heats Martian air up to nearly 1,500 degrees Fahrenheit (800 degrees Celsius). Within the device are six heat exchangers – palm-size nickel- alloy plates that protect key parts of the instrument from
Article & Photos Supplied by NASA/JPL-Caltech
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