Re: Mars Rover Not Responding - Update - NASA Makes Contact With Mars Rover

From: mitch (realtime_at_-no-spam-acm.org)
Date: 01/24/04

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    Date: Sat, 24 Jan 2004 14:59:55 -0800

    Ahh, how quickly we blame software. The actual problem appears to
    be hardware (see article below) that is causing the computer to
    reboot about once every minute. Last I heard from NASA, Spirit
    did an unexpected 73 Mbit dump of electrical subsystem information,
    which would seem to support NASA's theory of hardware failure, via
    the 128 Kbit/sec uplink to the Orbiter. And, BTW, it is NASA's
    software running on VxWorks that is allowing the reboot to occur
    due to a watchdog timer expiration, i.e., NASA's software is not
    resetting the timer before it expires. The OS has nothing to do
    with it, in this case. ;-)
    ---------------------------

    NASA fights to revive Spirit on Mars
    ====================================

    By Richard Stenger
    CNN

    (CNN) --Attempting to diagnose a nearly mute and temporarily delirious
    spacecraft more than 100 million miles away, NASA mission controllers
    said Friday that they suspect a hardware problem on the six-wheeled Mars
    rover may have caused a severe malfunction.

    The craft, Spirit, has sent back little more than beeps and sporadic
    data bursts since Wednesday, forcing NASA engineers to scramble for
    answers at an inopportune time: an identical robot ship is poised to
    land on the other side of Mars on Saturday night or Sunday morning.

    Cautioning that they will need more time to understand what went wrong,
    project engineers said they have determined that Spirit has rebooted or
    tried to reboot itself more than 60 times a day since the failure.

    The preliminary health checkup includes both bad news and good news for
    the $400 million mission, designed to search for evidence of water on
    the red planet in the ancient past. First the bad.

    "We will not be restoring functionality to Spirit for some time, for
    days or weeks, even in the best of circumstances," Pete Thiesinger, Mars
    rover project manager, told reporters at NASA's Jet Propulsion
    Laboratory in Pasadena, California.

       A measure of hope
       -----------------

    Now the good. NASA engineers think they can maintain the spacecraft's
    current health for some time, communicating simple commands and
    receiving simple replies, but nothing comparable to the flood of
    geological and photographic data from the first 18 days of the mission
    in Gusev Crater, a roughly 100-mile-wide pockmark thought to have once
    been filled with water.

    "I expect we will get functionality back from this rover," Thiesinger
    added. The chances that it will be perfect again are not good. But the
    chances that will not regain functionality are low, too, he said.

    The culprit remains a mystery, but engineers have pinpointed the time
    when the glitch began. Spirit was using an onboard motor to move its
    thermal spectrometer for a test when the motor unexpectedly conked out.

    After that, its messages to Earth became sporadic, feeble and in some
    cases garbled. More detective work determined that its processor
    repeatedly wakes up, attempts to load software data, finds a problem and
    then presses its own reset button.

    JPL engineers have coaxed Spirit back into regular and coherent contact
    with Earth, albeit in very simple conversations. They think one possible
    cause is that a hardware system has broken and affected the software
    somehow.

    "We're a long, long way from being done here, but we have serious
    problems and our ability to work around them is unknown," Thiesinger said.

       Into thin Martian air
       ---------------------

    If performing long-distance therapy on Spirit were not enough, NASA must
    guide an identical twin rover to a landing in Meridiani Planum, a
    high-elevation plain loaded with a mineral that often forms in the
    presence of water.

    The Martian atmosphere is much thinner there than it is where Spirit
    landed, and a recent dust storm in the region thinned it even further.
    The conditions mean that Opportunity's parachute will have a harder time
    slowing the craft as it prepares to land.

    To compensate, the craft will deploy its parachute much sooner before
    touchdown, which is scheduled for 12:05 a.m. ET.

    "This will be challenging because it's the highest-altitude landing that
    NASA has ever attempted," said Wayne Lee, the engineer in charge of
    Opportunity's entry, descent and landing.

    Find this article at:
    http://www.cnn.com/2004/TECH/space/01/23/spirit.contact/index.html

    Alf P. Steinbach wrote:
    > On 24 Jan 2004 07:45:20 -0800, eventhelix@hotmail.com (EventHelix.com) wrote:
    >
    >
    >>It seems to be a software problem. The rover is rebooting frequently.
    >>
    >>Who says there is no life on Mars? ... We have bugs.
    >
    > xWorks, who made the operating system for both this probe and
    > the previous American one that failed, see
    > <url: http://www.windriver.com/platforms/platformvdt/>, thinks the
    > following is a real advantage -- and perhaps so also did NASA:
    >
    > <quote>
    > Reduces time-to-market by cutting integration and testing ...
    > ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    >
    > typically the most time-consuming stages of the development process.
    > </quote>

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