[meteorite-list] Mars Exploration Rover Update - December 16, 2005

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Sun Dec 18 23:30:18 2005
Message-ID: <200512190428.jBJ4SlN20044_at_zagami.jpl.nasa.gov>

http://marsrovers.jpl.nasa.gov/mission/status.html#opportunity

OPPORTUNITY UPDATE: Robotic Arm Deployed - sol 668-674, Dec 16, 2005:

Opportunity successfully deployed its robotic arm on sol 671 (Dec. 13,
2005) and used it to position the microscopic imager. The cause of a
shoulder-joint motor stall during an attempt to deploy the arm on sol
654 appears to be a broken wire in the motor windings. The motor can
still be operated by changing one of the parameters so that more current
is delivered. However, the behavior is still being characterized, and
stalls of the motor can still occur while the motor parameters are being
adjusted. Analysis also continues for determining the best strategy for
keeping the arm unstowed even when it is not in use, so that the arm
could still position instruments on targets even if the motor with the
broken wire becomes unusable.

While parked at "Erebus Crater," Opportunity has completed a campaign of
atmospheric science, with sky surveys, photometry observations at
several times of day, and atmospheric observations with the miniature
thermal emission spectrometer. The rover also observed ground targets
with the panoramic camera and the miniature thermal emission spectrometer.

Sol-by-sol summaries:

Sol 668 (Dec. 10, 2005): The team had planned some targeted remote
sensing and atmospheric observations, but the plan did not get uplinked
due to issues with ground servers.

Sol 669: The uplink succeeded, and Opportunity performed targeted remote
sensing and atmospheric observations.

Sol 670: Early in the morning, the rover performed an atmospheric
observation. Later in the day, some stares with the miniature thermal
emission spectrometer were completed.

Sol 671: Results of diagnostic tests of the robotic arm were consistent
with the performance of a motor with a broken wire in one of the
windings. The motor can be operated in this configuration by modifying
motor parameters. By making the necessary changes, the arm was
successfully moved out of its stowed position. The team planned a
two-image-by-two-image mosaic with the microscopic imager and a reading
with the Moessbauer spectrometer. The first half of the mosaic completed
as planned, but the arm sequence was halted after that due to a stall of
the shoulder-joint motor.

Sol 672: Opportunity made atmospheric and photometric observations.

Sol 673: The plan was to complete the microscopic-imager mosaic that was
started on sol 671 and place the Moessbauer spectrometer on a target
called "Williams." However, the shoulder-joint motor stalled once again.
Targeted observations with the panoramic camera were completed as planned.

Sol 674 (Dec. 16, 2005): After analysis of the sol 673 stall, the team
redelivered a command sequence to close the microscopic imager's dust
cover and to position the alpha particle X-ray spectrometer for an
overnight integration on Williams. Opportunity's total odometry remains
at 6,502 meters (4.04 miles).
Received on Sun 18 Dec 2005 11:28:46 PM PST