[meteorite-list] Mars Rover Curiosity Can Choose Laser Targets on Its Own

[Ron Baalke]

http://www.jpl.nasa.gov/news/news.php?feature=6575

NASA Mars Rover Can Choose Laser Targets on Its Own
Jet Propulsion Laboratory
July 21, 2016

NASA's Mars rover Curiosity is now selecting rock targets for its laser 
spectrometer -- the first time autonomous target selection is available 
for an instrument of this kind on any robotic planetary mission.

Using software developed at NASA's Jet Propulsion Laboratory, Pasadena, 
California, Curiosity is now frequently choosing multiple targets per 
week for a laser and a telescopic camera that are parts of the rover's 
Chemistry and Camera (ChemCam) instrument. Most ChemCam targets are still 
selected by scientists discussing rocks or soil seen in images the rover 
has sent to Earth, but the autonomous targeting adds a new capability.

During Curiosity's nearly four years on Mars, ChemCam has inspected multiple 
points on more than 1,400 targets by detecting the color spectrum of plasmas 
generated when laser pulses zap a target -- more than 350,000 total laser 
shots at about 10,000 points in all. ChemCam's spectrometers record the 
wavelengths seen through a telescope while the laser is firing. This information 
enables scientists to identify the chemical compositions of the targets. 
Through the same telescope, the instrument takes images that are of the 
highest resolution available from the rover's mast.

AEGIS software, for Autonomous Exploration for Gathering Increased Science, 
had previously been used on NASA's Mars Exploration Rover Opportunity, 
though less frequently and for a different type of instrument. That rover 
uses the software to analyze images from a wide-angle camera as the basis 
for autonomously selecting rocks to photograph with a narrower-angle camera. 
Development work on AEGIS won a NASA Software of the Year Award in 2011.

"This autonomy is particularly useful at times when getting the science 
team in the loop is difficult or impossible -- in the middle of a long 
drive, perhaps, or when the schedules of Earth, Mars and spacecraft activities 
lead to delays in sharing information between the planets," said robotics 
engineer Tara Estlin, the leader of AEGIS development at JPL.

The most frequent application of AEGIS uses onboard computer analysis 
of images from Curiosity's stereo Navigation Camera (Navcam), which are 
taken routinely at each location where the rover ends a drive. AEGIS selects 
a target and directs ChemCam pointing, typically before the Navcam images 
are transmitted to Earth. This gives the team an extra jump in assessing 
the rover's latest surroundings and planning operations for upcoming days.

To select a target autonomously, the software's analysis of images uses 
adjustable criteria specified by scientists, such as identifying rocks 
based on their size or brightness. The criteria can be changed depending 
on the rover's surroundings and the scientific goals of the measurements.

Another AEGIS mode starts with images from ChemCam's own Remote Micro-Imager, 
rather than the Navcam, and uses image analysis to hone pointing of the 
laser at fine-scale targets chosen in advance by scientists. For example, 
scientists might select a threadlike vein or a small concretion in a rock, 
based on images received on Earth. AEGIS then controls the laser sharpshooting.

"Due to their small size and other pointing challenges, hitting these 
targets accurately with the laser has often required the rover to stay 
in place while ground operators fine tune pointing parameters," Estlin 
said. "AEGIS enables these targets to be hit on the first try by automatically 
identifying them and calculating a pointing that will center a ChemCam 
measurement on the target."

>From the top of Curiosity's mast, the instrument can analyze the composition 
of a rock or soil target from up to about 23 feet (7 meters) away.

"AEGIS brings an extra opportunity to use ChemCam, to do more, when the 
interaction with scientists is limited," said ChemCam Science Operation 
Lead Olivier Gasnault, at the Research Institute in Astrophysics and Planetology 
(IRAP), of France's National Center for Scientific Research (CNRS) and 
the University of Toulouse, France. "It does not replace an existing mode, 
but complements it."

The U.S. Department of Energy's Los Alamos National Laboratory in New 
Mexico leads the U.S. and French team that jointly developed and operates 
ChemCam. IRAP is a co-developer and shares operation of the instrument 
with France's national space agency (CNES), NASA and Los Alamos.

The Curiosity mission is using ChemCam and other instruments on the rover 
as the vehicle investigates geological layers on lower Mount Sharp. The 
rover's extended mission is analyzing evidence about how the environment 
in this part of Mars changed billions of years ago from conditions well 
suited to microbial life -- if life ever existed on Mars -- to dry, inhospitable 
conditions. For more information about Curiosity, visit:

http://mars.jpl.nasa.gov/msl

News Media Contact
Guy Webster
Jet Propulsion Laboratory, Pasadena, Calif.
818-354-6278
guy.webster at jpl.nasa.gov

Dwayne Brown / Laurie Cantillo
NASA Headquarters, Washington
202-358-1726 / 202-358-1077
dwayne.c.brown at nasa.gov / laura.l.cantillo at nasa.gov

2016-193