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10 Years In, Mars Rover Opportunity Suffers From Flash Memory Degradation
astroengine writes Mars Exploration Rover Opportunity has been exploring the Martian surface for over a decade — that's an amazing ten years longer than the 3-month primary mission it began in January 2004. But with its great successes, inevitable age-related issues have surfaced and mission engineers are being challenged by an increasingly troubling bout of "amnesia" triggered by the rover's flash memory. "The problems started off fairly benign, but now they've become more serious — much like an illness, the symptoms were mild, but now with the progression of time things have become more serious," Mars Exploration Rover Project Manager John Callas, of NASA's Jet Propulsion Laboratory in Pasadena, Calif., told Discovery News.
Memory bristles
Like Scottish thistles
Make operation tough
Plus the interplanetary stuff
Burma Shave
Get thee glass eyes, and, like a scurvy politician, seem to see things thou dost not.--King Lear
But to claim it under warranty, you have to return it to the manufacturer
If only they had over-engineered it last, this never would have happened!
http://mars.nasa.gov/mer/mission/status_opportunityAll.html
I don't know that one could expect similar behavior from the other banks on a similar schedule. This is fairly old technology in terms of design and software, so I don't think they're doing any sort of automatic wear leveling, for instance. It's probably "manually leveled" if at all. For all we know, bank 7 was used the most and it's worn out. Or, it's taking more total ionizing dose (TID) because of the physical location on the card. Or, it's just a process variation when making the flash chips themselves. They were probably fabricated in 2000, most likely at Micron, since for a 2003 launch, the computer was probably assembled by early 2002, if not earlier.
Or, the software is not optimized for "space flight use" but, rather, for "consumer camera memory card", which has a different read/write/erase pattern and error tolerance.
http://spinroot.com/gerard/pdf/25MC.pdf describes an improved file manager under development, but also describes the existing flash architecture.
I agree. It's had a fantastic run, but it'll be a real loss when it finally stops working.
Like everyone of us.
Achille Talon
Hop!
Explain how the results of research done two years ago could have been built into a probe launched ten years ago using technology from twenty years ago?
The article you link to is dated 2012 - the MER rovers launched in 2003. You do the math.
Put an 800 degree flame inside the electronic equipment you use the flash memory in - stand back, way back, and borrow a friend's phone, tablet, or PC to report the results back to us. (If they'll let you.)
Seriously, 800 degrees, even in a small space, is still a lot of heat to dissipate. It's more than enough to damage the solder connections of the flash chip, and probably enough to damage the socket it's plugged into.
These rovers were designed to last 90 days. The most broad plans extended to about a year if they were lucky. So no plans were made for every thing that could go wrong 5 to 10 years down the road.
The expected mission life of the rover was 90 days. It is currently on day 3885.
They expected to run out of power several years ago. Thus, they did not design other parts of the system to last as long as it has. Given the designed lifetime, it would have been absurd to add the extra weight of a heating system, if such a thing could even be powered at all.
For a car analogy, that would be like reinforcing your transmission because after 10,000,000 miles it starts to get a bit off-balance.
So, does that mean that NASA needs to go back to the plated wire memory and tape systems like the Honeywell systems that ran the Viking and Voyager systems for decades on Mars and in space?
Or in human terms, it would be like having a life expectancy of 75 years and developing Alzheimer's at the ripe old age of 3,237.
My sci-fi novel, Ghost Thief, is now available from Amazon.com.
There may be some possibility. That would, of course, have *definitely* added to the complexity and time taken to construct the rover. Which was done on the cheap, to meet a limited duration mission goal that it has vastly exceeded...without the extra complexity whose omission you find egregious.
Now I'll just fire up my Steampunk Mars Exploratron and off we go!
-- Tigger warning: This post may contain tiggers! --
This was known, and should have been exploited:
The rover is equipped with heaters. There is some possibility that simply placing the flash closer could have extended the life of the memory.
The rover's primary planned mission was 3 months and the extended mission plan was two years. It lasted 10 years and your upset they didn't design a way to bake the flash (offline) for four hours at 250C? Self heating flash did not exist, should they heat all the electronics? Invent a mechanism to remove the flash and put it in a little oven? Are you shutting down the rover's computer for this? How much complexity would that have added? How long would it take to develop?
There is such a thing as "good enough," and engineers that don't know that never ship usable product.
Some privacy policy Slashdot.
If the gov't has the power to insert birth announcements into Hawaiian newspapers decades old, then it can send new research to old NASA.
Table-ized A.I.