[meteorite-list] NASA Mars Team Teaches Old Rovers New Tricks to Kick Off Year Four

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Thu, 28 Dec 2006 16:17:35 -0800 (PST)
Message-ID: <200612290017.QAA22550_at_zagami.jpl.nasa.gov>

http://www.jpl.nasa.gov/news/news.cfm?release=2006-152

NASA Mars Team Teaches Old Rovers New Tricks to Kick Off Year Four
December 28, 2006

NASA's twin Mars rovers, nearing the third anniversary of their
landings, are getting smarter as they get older.

The unexpected longevity of Spirit and Opportunity is giving the space
agency a chance to field-test on Mars some new capabilities useful both
to these missions and future rovers. Spirit will begin its fourth year
on Mars on Jan. 3 (PST); Opportunity on Jan. 24. In addition to their
continuing scientific observations, they are now testing four new skills
included in revised flight software uploaded to their onboard computers.

One of the new capabilities enables spacecraft to examine images and
recognize certain types of features. It is based on software developed
for NASA's Space Technology 6 "thinking spacecraft."

Spirit has photographed dozens of dusty whirlwinds in action, and both
rovers have photographed clouds. Until now, however, scientists on Earth
have had to sift through many transmitted images from Mars to find those
few. With the new intelligence boost, the rovers can recognize dust
devils or clouds and select only the relevant parts of those images to
send back to Earth. This increased efficiency will free up more
communication time for additional scientific investigations.

To recognize dust devils, the new software looks for changes from one
image to the next, taken a few seconds apart, of the same field of view.
To find clouds, it looks for non-uniform features in the portion of an
image it recognizes as the sky.

Another new feature, called "visual target tracking," enables a rover to
keep recognizing a designated landscape feature as the rover moves.
Khaled Ali of NASA's Jet Propulsion Laboratory, Pasadena, Calif., flight
software team leader for Spirit and Opportunity, said, "The rover keeps
updating its template of what the feature looks like. It may be a rock
that looks bigger as the rover approaches it, or maybe the shape looks
different from a different angle, but the rover still knows it's the
same rock."

Visual target tracking can be combined with a third new feature --
autonomy in calculating where it is safe to reach out with the contact
tools on the rover's robotic arm. The combination gives Spirit and
Opportunity a capability called "go and touch," which is yet to be
tested on Mars. So far in the mission, whenever a rover has driven to a
new location, the crew on Earth has had to evaluate images of the new
location to decide where the rover could place its contact instruments
on a subsequent day. After the new software has been tested and
validated, the crew will have the option of letting a rover choose an
arm target for itself the same day it drives to a new location.

The new software also improves the autonomy of each rover for navigating
away from hazards by building better maps of their surroundings than
they have done previously. This new capability was developed by Carnegie
Mellon University, Pittsburgh, and JPL.

"Before this, the rovers could only think one step ahead about getting
around an obstacle," said JPL's Dr. John Callas, project manager for the
Mars Exploration Rovers. "If they encountered an obstacle or hazard,
they'd back off one step and try a different direction, and if that
direction didn't work they'd try another, then another. And sometimes
the rover could not find a solution. With this new capability, the rover
will be smarter about navigating in complex terrain, thinking several
steps ahead. It could back out of a dead-end cul-de-sac. It could even
find its way through a maze."

This is the most comprehensive of four revisions to the rovers' flight
software since launch. One new version was uplinked during the cruise to
Mars, and the rovers have switched to upgraded versions twice since
their January 2004 landings.

Callas said, "These rovers are a great resource for testing software
that could be useful to future Mars missions without sacrificing our own
continuing mission of exploration. This new software will be a baseline
for development of flight software for Mars Science Laboratory, but it's
also helpful in operating Spirit and Opportunity." NASA's Mars Science
Laboratory is a next-generation Mars rover in development for planned
launch in 2009.

Spirit and Opportunity have worked on Mars for nearly 12 times as long
as their originally planned prime missions of 90 Martian days. Spirit
has driven about 6.9 kilometers (4.3 miles); Opportunity has driven
about 9.8 kilometers (6.1 miles). Spirit has returned more than 88,500
images, Opportunity more than 80,700. All the raw images are available
online at http://marsrovers.jpl.nasa.gov/gallery/all/ .

Currently, Spirit is investigating rocks and soils near a ridge where it
kept its solar panels tilted toward the sun during the Martian winter.
Opportunity is exploring "Victoria Crater," where cliffs in the crater
wall expose rock layers with clues about a larger span of Mars history
than the rover has previously examined.

Opportunity's key discovery since landing has been mineral and
rock-texture evidence that water drenched and flowed over the surface in
at least one region of Mars long ago. Spirit has found evidence that
water in some form has altered mineral composition of some soils and
rocks in older hills above the plain where the rover landed.

Among the rovers' many other accomplishments:

-- Opportunity has analyzed a series of exposed rock layers recording
changing environmental conditions from the times when the layers were
deposited and later modified. Wind-blown dunes came and went. The water
table fluctuated.

-- Spirit has recorded dust devils forming and moving, events which were
made into movie clips. These provide new insight into the interaction of
Mars' atmosphere and surface.

-- Both rovers have found metallic meteorites on Mars. Opportunity found
one rock with a composition similar to a meteorite that reached Earth
from Mars.

NASA's Mars Technology Program and New Millennium Program sponsored
development of the new capabilities included in the new flight software.

JPL, a division of the California Institute of Technology, Pasadena,
manages the Mars Exploration Rover Project for the NASA Science Mission
Directorate. For images and information about the rovers, visit
http://www.nasa.gov/rovers . For descriptions of technologies being
developed for future Mars missions, see http://marstech.jpl.nasa.gov .
For information about the New Millennium Program's Space Technology 6
mission, see http://nmp.nasa.gov/st6/ .

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Media contact: Guy Webster (818) 354-6278
Jet Propulsion Laboratory, Pasadena, Calif.

2006-152
Received on Thu 28 Dec 2006 07:17:35 PM PST