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DART Succumbs to Fuel Problems

Posted by timothy on from the well-there-went-my-tax-payment dept.

qw0ntum writes "The AP reports that NASA's experimental DART (Demonstration of Autonomous Rendezvous Technology) spacecraft mission ended early when the craft's onboard computers detected a fuel-system problem. The craft, which was entirely computer-controlled, came within 300 feet of its target rendezvous target, a Pentagon satelite, before detecting the problem. Despite the failure, mission leaders 'called the mission a partial success because it demonstrated that an entirely computer-controlled craft could find a satellite in space.'"

25 of 137 comments (clear)

  1. They should do this mission again by TheKidWho · · Score: 5, Insightful

    They really should, in space rendevous is going to be a very important technology in the future, especially when the CEV needs to be assembled in orbit for a trip to the moon or mars, much easier to have it autonomously done.

    And this time, launch the thing off of a Falcon 1, not a $30million pegasus.

    1. Re:They should do this mission again by Anonymous Coward · · Score: 2, Interesting

      The most important part of the mission was accomplished. This sounds hard to believe since the mission it was supposed to perform appeared to be simple: go up, find a satellite, fly around it a couple of times, and then go away. What most news sites fail to mention is that DART was designed to find the satellite without ground or space support. Just GPS.

      The proving that GPS alone could allow spacecraft to navigate in space was the most important part of the mission. This part was accomplished. The precision GPS navigation towards the end of the mission was not accomplished. This is a pity, but not nearly as significant as the initial GPS navigation performed. It would be nice for this technology to be proved in the future, but it is not reasonable to believe that any normal rendevous in space in the near future would be done without communication between spacecraft. I don't think it is worth the money currently to put another DART into space for just this task. If DART failed altogether, I would say yes, but since it proved the most important part of its mission, couple the precision GPS navigation onto another research craft.

    2. Re:They should do this mission again by DerekLyons · · Score: 2, Insightful
      And this time, launch the thing off of a Falcon 1, not a $30million pegasus.
      Considering that Pegasus is a proven booster, and that the Falcon is vapoware... (Vaporware whose first flight is currently scheduled for 8 months after it's originally scheduled date...)
    3. Re:They should do this mission again by GroovBird · · Score: 2, Funny

      Actually, because rockets generally burn gasses (or liquids brought into gaseous state), they are kind of vaporware, aren't they?

  2. Lessons learned? by helioquake · · Score: 4, Insightful

    This partial failure is to show that it is not an easy stuff to launch a satellite and let it autonomously dock itself to another object.

    Imagine doing something similiar with the Hubble. Though it'd not be totally autonomous, many things could go wrong in the repair/deorbit mission, which can lead to a disaster. This is why, I think that, at the end the Hubble would be serviced by astronauts to prepare its deorbit.

    1. Re:Lessons learned? by myowntrueself · · Score: 3, Funny

      "This partial failure is to show that it is not an easy stuff to launch a satellite and let it autonomously dock itself to another object."

      No, its evidently its quite difficult.

      Just ask the Russians, who have been doing it with enormous success for decades and who have well-developed systems that have been proven to perform this function extremely reliably.

      It must be incredibly hard, if NASA have trouble with it.

      Oops sorry, that last bit was a troll.

      --
      In the free world the media isn't government run; the government is media run.
    2. Re:Lessons learned? by TheKidWho · · Score: 4, Informative

      The Russians do it by having an active system on both the spacecraft that is docking and the craft/satellite that is being docked to. It's much much easier to do it that way, what NASA was trying to do was have the spacecraft do it ALL by itself with absolutely no human intervention and no active docking systems on the targetted satellite.

      Oooo does the truth hurt troll?

    3. Re:Lessons learned? by Anonymous Coward · · Score: 5, Informative

      Enormous success? Certainly not complete success: the Russians almost lost MIR due to a problem with a Progress resupply spacraft in 1997.

      An automated docking spacecraft is a simpler design than DART. DART navigated only by GPS, received no navigation information from the Earth after it launched, and then once the satellite was located it navigated within 300 feet visually. DART failed to navigate within 15 feet and do maneuvers around the satellite prior to going into a parking orbit due to a fuel issue. I think it is obvious that the method that DART was using is much more complicated than used on Progress supply ships (which can count on a beacon from the space station and additional information from the Earth--not to mention a manual override).

      The difference between DART and Progress is that Progress requires ground and space support in order to dock. DART requires neither. In the future, if a successful DART 2 mission occurs, it may be possible to launch a spacecraft and forget about it until it docks or performs its mission (like a computer program). This could reduce costs for automated spacecraft (logisitics costs).

    4. Re:Lessons learned? by tsotha · · Score: 4, Interesting
      Certainly not complete success: the Russians almost lost MIR due to a problem with a Progress resupply spacraft in 1997.

      That's not fair to the Russians. They had a working system and were testing a new video system which would have been cheaper to operate, had it worked out. If they'd stuck with the original system everything would have been fine.

      In the future, if a successful DART 2 mission occurs, it may be possible to launch a spacecraft and forget about it until it docks or performs its mission (like a computer program). This could reduce costs for automated spacecraft (logisitics costs).

      I don't see how that can actually work out. The people you have standing around at launch aren't there to guide the spacecraft. You could hire one retired porn star for that. All those guys are there in case something goes wrong. You'll still need them even if the computer controlls the flight, for the same reason.

    5. Re:Lessons learned? by Nerull · · Score: 2, Informative

      The Progress/Mir accident was caused when Russia decided to save money by ditching the autopilot and having a human remotely dock Progress from Mir via a joystick remote control and looking out the window at it. He lost it against earth and it crashed into Mir. Their autodocking system had nothing to do with it.

      It did have a problem on Soyuz TMA-5, though. The astronauts had to take manual control. A thruster was not preforming at full power and the software overcompensated with the other thusters, approaching the ISS too fast.

    6. Re:Lessons learned? by myowntrueself · · Score: 4, Informative

      "The Progress/Mir accident was caused when Russia decided to save money by ditching the autopilot and having a human remotely dock Progress from Mir via a joystick remote control and looking out the window at it."

      Wrong; NASA insisted that the Russians develop and test methods to dock manually because NASA didn't trust the Russian computers.

      When they did it the NASA way, they had their first major accident in a docking maneuver.

      --
      In the free world the media isn't government run; the government is media run.
    7. Re:Lessons learned? by DerekLyons · · Score: 3, Interesting
      "The Progress/Mir accident was caused when Russia decided to save money by ditching the autopilot and having a human remotely dock Progress from Mir via a joystick remote control and looking out the window at it."

      Wrong; NASA insisted that the Russians develop and test methods to dock manually because NASA didn't trust the Russian computers.

      Wrong. NASA asked Russia to ensure a continued supply of docking computers (they are manufactured in the Ukraine, who insists on being paid in hard currency). Russia was so hard up for docking computers during Shuttle/MIR they salvaged them from Progress before it undocked and begged NASA to carry them back on the Shuttle!

      Russia decided to cheap it out and try a manual method instead. Then, they decided to perform the test with a crew that had already been in orbit for months, and whose training was questionable. Then, they made things worse by not outfitting the Progress with visual aids, and by not outfitting MIR with proper hardware (windows, cameras, viewing aids, rangefinding aids etc..), and by conducting a shitty approach against a bad background.

      Just a few weeks ago, Russia announced they had set up a factory to produce KURS computers in Russia, from Russian components. (Their native TORU system having proved problematical.)

  3. Finding satellites by vandoravp · · Score: 3, Funny

    isn't hard at all. In fact right now I can see one. It's big, bright, and has a man in it.

    Oh, you mean artificial satellites?

    *squints harder*

  4. Autonomous Rendezvous Technology? by WMD_88 · · Score: 2, Funny

    NASA is copying Apple now?

  5. I, for one . . . by Council · · Score: 4, Funny

    It came within 300 feet of the Pentagon satellite before suffering a "mysterious failure".

    Oh, just come right out and say it. The craft was death-rayed by the skittish Pentagon satellite.

    --
    xkcd.com - a webcomic of mathematics, love, and language.
  6. Re: DART Succumbs to Fuel Problems by kabz · · Score: 5, Funny

    Well, you can hardly blame NASA for leaving the thing a bit short...

    Gas is $2.35 a gallon in Houston !

    --
    -- "It's not stalking if you're married!" My Wife.
  7. Partial success... by gabecubbage · · Score: 5, Funny

    I consider my recent trip to the bathroom a partial success, too. After all, I SAW the toilet.

  8. units again? by jonbrewer · · Score: 2, Insightful

    "When we started doing precise maneuvers, we started seeing excessive propellant consumption," Snoddy said. "The mission as designed, when it runs out of gas, completes itself."
    There were some navigation errors but no indication of a fuel leak, he said in a conference call. A NASA investigation board will search for the cause of the problem.

    Now when it turns out that the fuel system was reporting litres consumed per hour and the central system was thinking gallons per hour, is NASA going to give up on using English units? "472 miles above Earth"? "300 feet of the satellite"? Wankers.

  9. Orbital not NASA by TornNight · · Score: 3, Informative

    Orbital Designed, Manufactured, and launched DART.
    It's mostly their fault.
    http://www.orbital.com/NewsInfo/MissionUpdates/dar t.html

    --
    Hey watch this! Splat...
  10. Re: DART Succumbs to Fuel Problems by dgatwood · · Score: 4, Funny
    Ah. I thought maybe they just used the same 3.8L V6 as my Windstar. :-D

    For people who don't get the joke, there was a design flaw in that engine (also used in the Mustang) for a couple of years that caused oil to corrupt the air intake manifold, resulting in vacuum lines getting clogged. The end result is that the fuel system starts misbehaving badly and the computer thinks that both banks of the engine are running exceptionally lean.

    I ordered parts to repair mine just seconds before reading this story, so I laughed pretty hard.... I suddenly feel very gratified that my fuel problems didn't happen in orbit.

    --

    Check out my sci-fi/humor trilogy at PatriotsBooks.

  11. always wanted to try one of these... by dahlek · · Score: 2, Funny

    I for one welcome our new autonomous semi-successful satellite finding space-craft overlords!

    --
    dahlek (will you squirm when you are pecked
  12. The $110 million mission by Anonymous Coward · · Score: 2, Funny

    For 11 hours of productivity. Go NASA!

    1. Re:The $110 million mission by imsabbel · · Score: 2, Funny

      Building a fully automated probe: 70 Million$
      Lauch into LEO via rocket: 40 Million$
      One fillup with propellant for end-naviagation: 50$
      Failing the mission because you were cheap on the wrong end: Priceless

      (values guesses that should be in the right order of magnitude)

      --
      HI O WISE PRINCE. WHT TOOK U SO DAM LONG?
  13. Re: DART Succumbs to Fuel Problems by Legion303 · · Score: 2, Funny

    Hey, it's NASA. They airlifted the fuel from Houston.

  14. Mod Parent up by johnny+cashed · · Score: 3, Informative

    This is a complex issue. The Kurs system was developed and manufactured in Ukraine. After the breakup of the Soviet Union, Ukraine was free to charge whatever they wanted for the system. Toru was designed (in Russia) as a manual backup system. KURS being primary and automatic. Ukraine inherited the intellectual property of the Kurs system and Russia could not just copy it, they had to license it or buy it from Ukraine. To put this in context, the former Soviet Union was going thru an economic meltdown. So they have little money to develop a new system or license the old Kurs system, or even buy them from Ukraine, which is having its own economic problems, and probably couldn't produce them on a timely basis as well. There is no simple answer for this, and it wasn't because the russians were cheap, they just had no money. Computers are made up of a lot of components, and if your suppliers are unable to supply parts, you cannot make the computers. The broken Soviet Union was an economic mess. Think of what would happen if the US broke up in to 50 independent states. What a clusterfuck that could be (or maybe will be). This link for more on the crash: http://human-factors.arc.nasa.gov/ihh/spatial/pape rs/pdfs_se/Ellis_2000_collision_in_space.html/