Tech Briefs Magazine - February 2022 - MD-9

the end of OPTIMISM's robotic arm,
they'll be testing the newly installed
Adaptive Caching Assembly for the
first time in the Mars Yard. The
assembly on Perseverance is responsible
for storing rock and sediment
samples. Some or all of these initial
samples could be among those returned
to Earth by a future mission.
" Now we can do it end-to-end in
the test bed, " said the Vehicle System
Ted Bed systems engineering lead,
Jose G. Trujillo-Rojas. " Drill into the
rock, collect the core sample, and
now we have the mechanism responsible
to cache that sample in the
cylinder. "
And if problems arise on Perseverance
on Mars, OPTIMISM can
be used as a platform to figure out
what went wrong and also how to
fix it.
Drilling core samples from terrestrial
rocks in the Mars Yard and
sealing them in metal tubes is not
as straightforward as it might sound.
JPL's Mars team provides a variety
of rock types for OPTIMISM to drill
through, since the exact nature of
the rock Perseverance will encounter
often can't be known in advance.
Terrain is a variable, too: One previous
test with the robotic arm involved
parking the rover on a slope,
then instructing it to drill.
" There was a possibility that the
rover might slip, " Trujillo-Rojas said.
" We wanted to test that first here
on Earth before sending instructions
to the rover on Mars. That was
scary, because you can imagine if you
drill this way, and the rover slightly
slipped back, the drill could have
gotten stuck. "
OPTIMISM drilled the core successfully,
suggesting Perseverance
also could pull off drilling on a slope
if required.
With longer drives in Perseverance's
near future, another job for the Earthbound
twin will involve
presenting
new challenges to the rover's autonomous
navigation system, or AutoNav.
Perseverance uses a powerful computer
to make 3D maps using rover images of
the terrain ahead and uses those maps
to plan its drive with minimal human
assistance.
In Mars Yard tests, the twin rover
might pause as it " thinks through "
Motion Design, February 2022
MD Automation Control Application 0222_1.indd 9
The engineering models of both the Curiosity Mars rover (foreground) and the Perseverance Mars rover share space
in the recently expanded garage at the Mars Yard. (Photo: NASA JPL-Caltech)
several possible choices - or even decides,
unexpectedly, to avoid obstacles
altogether and just go around.
Of course, OPTIMISM and its human
team must contend with environmental
factors very different from those
encountered by Perseverance, which is
built for freezing temperatures and intense
radiation. Earth's stronger gravity
required OPTIMISM's metal wheels to
be thicker than its Martian counterpart's.
And its electronics sometimes
must be cooled to avoid damage from
Southern California's summer temperatures
- the opposite of the problem
caused by deep cold on Mars.
The rover twin's testing and staffing
schedules had to contend with COVID19.
Now, a revamped OPTIMISM is
ready to get back to work.
This article was written by Pat Brennan,
science writer, Jet Propulsion Laboratory,
NASA. For more information, visit http://
info.hotims.com/82318-282.
9
Cov
ToC
1/18/22 9:19 AM

http://info.hotims.com/82318-282 http://info.hotims.com/82318-800

Tech Briefs Magazine - February 2022

Table of Contents for the Digital Edition of Tech Briefs Magazine - February 2022