PDS logoPlanetary Data System
PDS Information
Find a Node - Use these links to navigate to any of the 8 publicly accessible PDS Nodes.

This bar indicates that you are within the PDS enterprise which includes 6 science discipline nodes and 2 support nodes which are overseen by the Project Management Office at NASA's Goddard Space Flight Center (GSFC). Each node is led by an expert in the subject discipline, supported by an advisory group of other practitioners of that discipline, and subject to selection and approval under a regular NASA Research Announcement.
Click here to return to the Photojournal Home Page Click here to view a list of Photojournal Image Galleries Photojournal_inner_header
Latest Images  |  Spacecraft & Technology  |  Animations  |  Space Images App  |  Feedback  |  Photojournal Search  

PIA02156: Opportunity's Arm in 'Hover-Stow' Position
 Target Name:  Mars
 Is a satellite of:  Sol (our sun)
 Mission:  Mars Exploration Rover (MER)
 Spacecraft:  Opportunity
 Instrument:  Navigation Camera
 Product Size:  1024 x 1024 pixels (w x h)
 Produced By:  JPL
 Full-Res TIFF:  PIA02156.tif (1.05 MB)
 Full-Res JPEG:  PIA02156.jpg (147.6 kB)

Click on the image above to download a moderately sized image in JPEG format (possibly reduced in size from original)

Original Caption Released with Image:

In January 2006, NASA's Mars Exploration Rover team adopted a new strategy for carrying Opportunity's robotic arm (the instrument deployment device with its turret of four tools at the end) when the rover is driving.

On short drives over smooth terrain, Opportunity now holds the arm in a "hover-stow" position as shown in this image taken by the navigation camera during the rover's 706th Martian day, or sol (Jan. 18, 2006), with elbow forward and the tool turret held above the rover deck. (In this image, the Moessbauer spectrometer is facing upwards, the alpha particle X-ray spectrometer faces to the right and the rock abrasion tool faces to the left). On longer or rougher drives, Opportunity still holds the arm in the original stow position used throughout the mission, tucked underneath the deck.

During Opportunity's 654th sol (Nov. 25, 2005), symptoms began appearing that have been diagnosed as a broken wire in the motor windings for the azimuth actuator at the shoulder joint, a motor that moves the arm from side to side. The motor still works when given extra current, but the change in strategy for stowing the arm results from concern that, if the motor were to completely fail with the arm in the original stow position, the arm could no longer be unstowed for use. If that motor were to fail while the arm is in the hover-stow position, the arm could still be manipulated for full use of the tools on the turret. However, the hover-stow position gives less protection to the arm during drives. Concern about protecting the arm during drives led to the compromise strategy of using hover-stow only during short, smooth drives.

Image Credit:
NASA/JPL-Caltech

Image Addition Date:
2006-02-02