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What's Inside the Mars Rovers

Posted by michael on from the remote-root dept.

Captain Zion writes "Space.com has a story about the hardware and software of Mars Rovers Spirit and Opportunity. Basically, they're radiation-shielded, 20MHz PowerPC machines wirh 128Mb RAM and 256Mb of flash memory, running VxWorks. I wonder if I could make a nice firewall with one of these for my home network..."

5 of 458 comments (clear)

  1. Radiation hardness by swordboy · · Score: 5, Interesting

    Does anyone know what the deal was with the flash memory that caused the outage? I heard something about a "solar event" that caused a problem with the flash memory that led to the outage. It was subsequently resolved by disabling the flash. If so, BAE Aerospace has a possible solution with their upcoming line of rad-hard memory.

    --

    Life is the leading cause of death in America.
    1. Re:Radiation hardness by TwistedGreen · · Score: 5, Interesting
      It appears to be a software error, and not hardware-related. It actually looks like it ran out of swap space and the OS crashed. This article explains what they think happened, and this article has more information on their recovery plans.

      A quote:
      It is now believed that the rover's flash memory had become so full of files that the craft couldn't manage all of the information stored aboard. Spirit bogged down because it didn't have enough random access memory, or RAM, to handle the current amount of files in the flash -- including data recorded during its cruise from Earth to Mars and the 18 days of operations on the red planet's surface.
      Raises some interesting questions about software reliability, I think. Did nobody think about running out of disk space?
  2. Re:Self-warming by Cyclopedian · · Score: 5, Interesting
    To survive the frigid Martian night, MER computers are housed in warm electronics boxed heated by a combination of electric heaters, eight radioisotope heater units as well as the natural warmth from the electronics themselves.[Emphasis added by me]

    If obsessed environmentalists don't like NASA sending up probes with any radioactive material ('it might blow up, ohh..'), then how did this little tidbit get by them? Do they consider it non-radioactive? If they're only concerned by radioactive propulsion systems, then I think they're a bunch of hypocrites. Radioactivitiy is radioactivity whether it's propulsion or heating.

    If they don't mind it, then let's send up those dune buggies with RTG and 18-inch wheels and cover a lot more of Mars.

    -Cyc

    --
    /.'s 10 Millionth
  3. Re:I hope the flash memory was not commodity hardw by Rootbear · · Score: 5, Interesting

    There is very little on the Rovers that is "commodity" in any sense. The CCD image sensors, the computers, everything, is all custom made. Everything has to be made to withstand the rigors of flight and the harsh environments of space and Mars. The CPU does not have a backup, which is a bit unusual for NASA (I'm a contractor at NASA/Goddard, but not involved in any flight missions). However, the particular computer used on the rovers (the RAD6000) has a very good record. There are something like 150 in use on various spacecraft and they've all worked very well.

    And the flash memory has probably not failed. It seems to have been a software problem, not hardware.

    Rootbear

  4. space shuttle uses 1969-vintage ibm 360 computers by peter303 · · Score: 5, Interesting

    The space shuttles run on five AP-101 computers, originally designed in 1969. The started with 32 kilowords of magnetic core memory for radiation protection, since upgraded to semiconductor memory. These computers were chosen due to their success in the Apollo, Skylab, and B52. For science and personal work the astronaut specialists usually bring personal laptops which are thousnds of times more performant.