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Curiosity Rover On Standby As NASA Addresses Computer Glitch
alancronin writes "NASA's Mars rover Curiosity has been temporarily put into 'safe mode,' as scientists monitoring from Earth try to fix a computer glitch, the US space agency said. Scientists switched to a backup computer Thursday so that they could troubleshoot the problem, said to be linked to a glitch in the original computer's flash memory. 'We switched computers to get to a standard state from which to begin restoring routine operations,' said Richard Cook of NASA's Jet Propulsion Laboratory, the project manager for the Mars Science Laboratory Project, which built and operates Curiosity."
Are we talking a temporary issue that can be resolved by re-flashing the memory in question or is one of the cells damaged in some un-recoverable way? Either way there are solutions but the latter is far more serious.
const int one = 65536; (Silvermoon, Texture.cs)
SJW, n: "Someone I don't like, and by the way I'm a fuckwit" - AC
Who else has a feeling that someone fitted in a module backwards?
Either that, or a dead cell or two.
Nobody who has read TFA has that feeling. Curiosity has been running since Aug. 6, 2012 on your putative "backwards module".
Sig Battery depleted. Reverting to safe mode.
How does it feels to SSH with a ~45 minutes delay. Wait: why bother encrypting? Just telnet!
This may be of some interest http://www.cpushack.com/space-craft-cpu.html
Only the State obtains its revenue by coercion. - Murray Rothbard
"NOOOO! I should've selected Safe mode WITH Networking!"
solutions: "someone fitted a module in backwards" "Why didnt they simply do X instead of Y" Do you seriously think the people who work for NASA, the same ones who sent a group of men to the moon and back, rovers to mars, Voyager to Deep Space, shuttles, space stations, et all can be out thought by YOU? And from the comfort of your Lazy Boy Chair, no less?! Wow. Surely you can come to respect these these men and women have given countless hours of thought, simulation, and planning to these missions. In fact, many have dedicated their lives to this engineering. Surely you can respect that those involved in this mission did not simply put the red wire where the blue one should have gone. Thats sorta insulting. Peace out
Nobody who has read TFA has that feeling.
You could actually explain it to him rather than choosing to go all holier than thou. Here, I'll do it for you.
Who else has a feeling that someone fitted in a module backwards? Either that, or a dead cell or two.
The A-side flux capacitor was somehow depolarized, perhaps by a cosmic ray impact event. They're hoping to fix it by reinitializing the quantum warp matrix.
#DeleteChrome
I once had to fix a server some 6000 km away due to a corrupted disk. Doing pdisk and modifying fstab over ssh and then a reboot. You just check and recheck to make sure you did it right and just hope you get a ping a few minutes later.
Can't imagine how these guys feel. 45 min ping and it isn't like they could ask someone to go turn it off and on again.
Good luck to the guys working on this.
On the whole I am sure everyone does respect NASA, but they do have "previous" on things far simpler than the random slashdotter obtuse suggestions:
Newtons or pound-force?
I don't think anyone is suggesting that simple mistakes were the cause in this case - but the above link may help explain why a little leg-pulling by slashdotters is not crossing any lines.
"Peace out"
Didn't Apple just disable Flash again? Coincidence? Knew they should have turned off remote updating on the Rover's Mac Mini.
But the rover's actually on Venus because of it.
Table-ized A.I.
The Galileo Jupiter atmosphere probe actually had a parachute-related part put on backward. It almost ruined the mission. They got lucky and the shaking from atmospheric drag eventually shook the high-altitude parachute off the bad lock barely in time before it could have damaged the probe.
Doesn't hurt to ask, although knowing more about the hardware may allow you to give more specific advice, such as "part X could be put in backward and still mostly work without early detection according to simulation Y."
Table-ized A.I.
Check out the official rover press kit for a summary of the computer design (http://mars.jpl.nasa.gov/msl/news/pdfs/MSLLanding.pdf) Page 42 in particular:
"Curiosity has redundant main computers, or rover compute elements. Of this “A” and “B” pair, it uses one at a time, with the spare held in cold backup. Thus, at a
given time, the rover is operating from either its “A” side or its “B” side. Most rover devices can be controlled by either side; a few components, such as the navigation camera, have side-specific redundancy themselves. The computer inside the rover — whichever side is active — also serves as the main computer for the rest of the Mars Science Laboratory spacecraft during the flight from Earth and arrival at Mars. In case the active computer resets for any reason during the critical minutes of entry, descent and landing, a software feature called “second chance” has been designed to enable the other side to promptly take control, and in most cases, finish the landing with a bare-bones version of entry, descent and landing instructions.
Each rover compute element contains a radiation-hardened central processor with PowerPC 750 architecture: a BAE RAD 750. This processor operates at up to 200 megahertz speed, compared with 20 megahertz speed of the single RAD6000 central processor in each of the Mars rovers Spirit and Opportunity. Each of Curiosity’s redundant computers has 2 gigabytes of flash memory (about eight times as much as Spirit or Opportunity), 256 megabytes of dynamic random access memory and 256 kilobytes of electrically erasable programmable read-only memory.
The Mars Science Laboratory flight software monitors the status and health of the spacecraft during all phases of the mission, checks for the presence of commands to execute, performs communication functions and controls spacecraft activities. The spacecraft was launched with software adequate to serve for the landing and for operations on the surface of Mars, as well as during the flight from Earth to Mars. The months after launch were used, as planned, to develop and test improved flight software versions. One upgraded version was sent to the spacecraft in May 2012 and installed onto its computers in May and June. This version includes improvements for entry, descent and landing. Another was sent to the spacecraft in June and will be installed on the rover’s computers a few days after landing, with improvements for driving the rover and using its robotic arm."
And according to a release they issued after landing, both computers receive the same updates and are running the same software (not a version or 2 behind like others have suggested): http://mars.jpl.nasa.gov/news/whatsnew/index.cfm?FuseAction=ShowNews&NewsID=1305
Who actually fabs the chips and circut boards used by NASA?
"American Components, Russian Components, all the same, all made in Taiwan!"
Lev Andropov - on board of MIR
Questions raise, answers kill. Raise questions to stay alive.
Ok lets assume a cosmic ray corrupted some random block of flash memory...so what? Why should that lead to failure to upload anything or enter sleep mode?
I can only assume there is integrity check for block level I/O from flash and it just did not try to load garbage without knowing it. If it were any old PC app this would be perfectly acceptable behavior.
However for ultra expensive spacefaring things I would expect it to be designed to still try and be useful even if the southbridge cought fire.
Noooooo!
Have gnu, will travel.
If only the good computer could perform the Jedi Mind Meld on the other!
E.E. / firmware guy here... Corrupted files, and so far not even a mention of a potential software problem?
Even considering radiation out in space, it seems that it's still easier to get the hardware right than the software / firmware. I'm not jumping to any conclusions, but my first guess would be some kind of rare and unanticipated race condition, or some rarely-executed leg of the filesystem / logging software, etc.
I'm probably cynical from having worked on lots of safety-critical systems for a while, but it just seems often convenient to throw alpha particles under the bus and not even question, perhaps gently, if perhaps there is some latent, obscure bug which just crapped all over the flash.
Btw, TFA?
The Fucking Article
What about that earth-shaking discovery Curiosity made that this news will be put down into history? I still haven't heard about it. Here's the link http://science.slashdot.org/story/12/11/20/1511232/what-earth-shaking-discovery-has-curiosity-made-on-mars
Sometimes 'nothing' is news. As in this case. Apparently the locals want more bloviation threads, and not news threads. I'm sure that they will get their wish.
Fugue for Aaron Swartz
Don't you mean the Vulcan We-Are-Not-Droids trick?