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 accelerometers.
“The reason we’re doing this is that one of the gyroscopes 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, CA.