Swapping motion-sensing units

August 13, 2013 by Guy Webster, NASA

This artist's concept of the Mars Reconnaissance Orbiter. Credit: NASA/JPL
(Phys.org) —NASA's Mars Reconnaissance Orbiter is switching from one motion-sensing device to a duplicate unit onboard.

The veteran orbiter relies on this inertial measurement unit (IMU) for information about changes in orientation. This information is important for maintaining spacecraft attitude and for pointing the orbiter's large antenna and science-observation instruments.

The spacecraft has two identical copies of this motion-sensing device, called IMU-1 and IMU-2. Either of them can be used with either of the spacecraft's redundant main computers. Each contains three gyroscopes and three .

"The reason we're doing this is that one of the on IMU-1 is approaching its end of life, so we want to swap to our redundant unit early enough that we still have some useful life preserved in the first unit," said Mars Reconnaissance Orbiter Mission Manager Reid Thomas of NASA's Jet Propulsion Laboratory, Pasadena, Calif.

The orbiter began investigating Mars in 2006. Since completing its primary science phase in 2008, it has continued to work as an extended mission.

The swap has been planned for this week, with procedures expected to take less than two days before the orbiter resumes its normal functions of from orbit and communication relay for Mars rovers.

"To make sure we have a smooth transition, regaining attitude knowledge as quickly as possible, we will power off all instruments, do the IMU swap, maneuver to sun point, do the IMU swap, and then put the spacecraft into safe mode," Thomas said. "The process re-initializes the spacecraft's knowledge of its attitude."

IMU-2 has been used previously, but IMU-1 has been used much more. After the swap, IMU-1 will remain available if needed for short periods.

The Mars Reconnaissance Orbiter has provided more data about Mars than all other earlier and current missions combined. It also relays to Earth information from both of NASA's active Mars rovers, Opportunity and Curiosity, sharing that function with the NASA Mars Odyssey orbiter.

Explore further: Mars longevity champ switching computers

More information: mars.jpl.nasa.gov/mro/

Related Stories

Mars longevity champ switching computers

November 2, 2012

(Phys.org)—NASA's Mars Odyssey orbiter, already the longest-working spacecraft ever sent to Mars, will switch to some fresh, redundant equipment next week that has not been used since before launch in 2001.

Orbiter enters, then exits, standby safe mode

July 16, 2012

(Phys.org) -- NASA's Mars Odyssey orbiter experienced about 21 hours in a reduced-activity precautionary status ending at about 10 a.m. PDT (1 p.m. EDT) on Thursday, July 12.

Mars Odyssey orbiter out of precautionary 'safe mode'

June 20, 2012

(Phys.org) -- NASA's Mars Odyssey orbiter has been taken out of a protective status called safe mode. Remaining steps toward resuming all normal spacecraft activities will probably be completed by next week.

Recommended for you

Rosetta witnesses birth of baby bow shock around comet

December 12, 2018

A new study reveals that, contrary to first impressions, Rosetta did detect signs of an infant bow shock at the comet it explored for two years – the first ever seen forming anywhere in the solar system.

The epoch of planet formation, times twenty

December 12, 2018

Astronomers have cataloged nearly 4,000 exoplanets in orbit around distant stars. Though the discovery of these newfound worlds has taught us much, there is still a great deal we do not know about the birth of planets and ...

Juno mission halfway to Jupiter science

December 12, 2018

On Dec. 21, at 8:49:48 a.m. PST (11:49:48 a.m. EST) NASA's Juno spacecraft will be 3,140 miles (5,053 kilometers) above Jupiter's cloud tops and hurtling by at a healthy clip of 128,802 mph (207,287 kilometers per hour). ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.