NASA’s Curiosity rover has finally seen repairs to its ChemCam autofocusing system performed. The ChemCam (Chemistry and Camera) instrument gathers information about the Martian landscape by first shooting laser pulses at rocks and other interesting features, then taking spectrometer readings of resulting sparks. The laser rangefinder that the rover employed had failed a few months ago, in November, which made snapping a pic on Mars something of a chore for the Curiosity team.
Before the rover repairs, the team had to take multiple pictures in hopes that one would be suitable.
Without the laser rangefinder, the ChemCam became far less user-friendly and effective. The team was forced to instruct the rover to take nine pictures of an object of interest (each in a different focus) just to capture one sharp picture, which would then be transmitted to Earth. Although the main laser, the one that shoots pulses at objects, was still fully functional, it needed the rangefinder laser to find an ideal distance.. The laser analysis would only work if the telescope projecting the laser to the target was in focus.
Rover repairs consisted of a 40-kilobyte software patch.
The rover team began working on a software fix for the ChemCam in December. After completing the patch, they tested it on a ChemCam clone in a laboratory in Los Alamos. Subsequently, they tested at another facility in France, and then on a rover testbed at NASA’s Jet Propulsion Laboratory. Finally, last week, NASA gave the team the thumbs up to implement the patch.
Software patch actually improves quality of pictures and analysis versus original.
The Curiosity rover and ChemCam are now back at work, capturing images and performing laser analysis. Perhaps surprisingly, though, the rover team is still using the method of taking multiple pictures of an object. However, the ChemCam now uses the pictures to automatically select the perfect focus for the final image and laser analysis. Team members claim that they believe that incoming images and analyses taken with the new patch in place will now actually be of a higher quality than those taken with the old software.