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Software Patch Fixes Mars Curiosity Rover's Auto-focus Glitch
An anonymous reader writes: Scientists from Los Alamos National Laboratory have successfully uploaded and applied a software patch to NASA's Curiosity Rover on Mars. The patch fixes a focusing problem that cropped up in November when the laser that helps to focus one of its cameras failed. "Without this laser rangefinder, the ChemCam instrument was somewhat blind," said Roger Wiens, ChemCam principal investigator at Los Alamos. "The main laser that creates flashes of plasma when it analyzes rocks and soils up to 25 feet [7.6 meters] from the rover was not affected, but the laser analyses only work when the telescope projecting the laser light to the target is in focus." Before the fix, scientists had to shoot images at nine different focus settings to distill a decent set of data. Now, they say the new software results in better images in a single shot than even before the laser broke down. The program that runs the instrument is only 40 kilobytes in size.
Apollo space program is documented in great detail. Even the software running in the flight computers is nowdays available and you can run the whole thing in a virtualized guidance computer. http://www.ibiblio.org/apollo/
Does anyone have any idea what's the case with probes and landers? I know they are mostly running VxWorks, but I'd love to take a peek on how some of the routines are actually implemented.
This fix still requires much of the resources of the previous method, essentially bracketing the shot and picking the best one. This means it will still take just as long to obtain each image, but apparently that wasn't a huge problem. What this saves is something precious though: bandwidth. Now the rover is picking the best shot, instead of sending a bunch of blind guesses and making us sort it out. I suspect that if the bandwidth wasn't precious, they wouldn't have bothered improving on the existing workaround, so it must have been worth all the trouble.
How is the Riemann zeta function like Trump rallies? Both have an endless number of trivial zeros.
thats four times LiteOS! Get some Huawei developers work on this, and they'll reduce this patch to 64 bytes.
We need these guys to work on Firefox. Chromium too! Hell, just turn them loose on Windows!
"Windows is like the faint smell of piss in a subway: it's there, and there's nothing you can do about it." - Charlie Br
If I read the article(s) correctly, problem was caused by failure of a small 2nd laser used for range finding. It seems that failure wasn't solved. Permanently out of action? Who knows.
Workaround was to take several shots at different focus settings, and have home base sort out the data. Improved workaround is to take several shots at different focus settings, have software on-site figure out which are the best, and only send that data back home.
If you are going to have a story like this it would be good form to remember the H, aka HOW from who,what,when,where, why and HOW of a journalism article. At some point in the past this was a site oriented to the technical community, most of whom are very interested in the how. You might even think that for the most part the when, why, where and who are all at the who cares level. (Mars being an exception)
Nobody in their right mind is going to write rover code in assembly. Too much work, and too much chance of a silly mistakes fucking things up, while the actual code saving is not much. It's much easier and cheaper to add some extra memory instead.
"Now, they say the new software results in better images in a single shot than even before the laser broke down."
So it was a good Oportunity to pay some technical debt.