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Space United States Science

DART Succumbs to Fuel Problems 137

Posted by timothy 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.'"
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DART Succumbs to Fuel Problems More

DART Succumbs to Fuel Problems

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  • They should do this mission again (Score:5, Insightful)

    by TheKidWho ( 705796 ) on Saturday April 16, 2005 @11:18PM (#12259173)
    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.

    • Re:They should do this mission again (Score:2, Interesting)

      by Anonymous Coward
      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 pre
    • There is no need for autonomy in orbit--they could do the entire thing via teleoperation.

      And that's what they should do for now: get teleoperations and telepresence between orbital vehicles and the ground worked out. That's useful not just for operating vehicles in orbit from the ground, it's potentially also useful for telepresence during planetary exploration--for most planetary operations, even if you send astronauts, there is little reason for them to actually land on the planet.
    • 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...)
    • I've done it lots of times! Ever played BARIS?

      :)

  • Lessons learned? (Score:5, Insightful)

    by helioquake ( 841463 ) * on Saturday April 16, 2005 @11:19PM (#12259179) Journal
    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.

    • Re:Lessons learned? (Score:4, Funny)

      by myowntrueself ( 607117 ) on Saturday April 16, 2005 @11:23PM (#12259203)
      "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.

      • Re:Lessons learned? (Score:4, Informative)

        by TheKidWho ( 705796 ) on Saturday April 16, 2005 @11:36PM (#12259269)
        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?

      • Re:Lessons learned? (Score:5, Informative)

        by Anonymous Coward on Saturday April 16, 2005 @11:49PM (#12259320)
        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).
        • Let's just hope they don't forget one if (when) a DART doesn't actually do it's job.

          How often have we started something, and then fogotten about it.
        • The Mir accident was due to human error actually. They try to dock it manually, and the operator miscalculated the lateral course deviation, because he was only relying on the one dimensional radar beacon.

        • Re:Lessons learned? (Score:5, Interesting)

          by tsotha ( 720379 ) on Sunday April 17, 2005 @01:44AM (#12259836)
          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.

          • 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.

            Hmmm. Interestign idea. I can forsee a return to the era when spacecraft launches were media events...
        • a SPAcraft?

          I need one of those!!!

        • Re:Lessons learned? (Score:3, Informative)

          by Nerull ( 586485 )
          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, approac

          • Re:Lessons learned? (Score:5, Informative)

            by myowntrueself ( 607117 ) on Sunday April 17, 2005 @02:25AM (#12259989)
            "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.

            • Re:Lessons learned? (Score:4, Interesting)

              by DerekLyons ( 302214 ) <fairwater@gmaLISPil.com minus language> on Sunday April 17, 2005 @05:06AM (#12260513) Homepage
              "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.)

              • Mod Parent up (Score:3, Informative)

                by johnny cashed ( 590023 )
                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
        • According to "Automated Rendezvous and Docking of Spacecraft" by Wigbert Fehse, the russian automated docking system, "Kurs," is "designed to provide all required navigation measurements during the entire approach from a few hundreds of kilometers down to contact." In other words, it does not require ground or space support to dock. This is also confirmed on:

          http://www.nasa.gov/missions/science/dart_into_spa ce.html [nasa.gov]

          As mentioned in other posts, the russians also developed a manual joystick/video docking

          • No, the benefit of the American system is it allows docking with a satelite that wasn't designed for automatic docking. Do you have a new, cost effective way to repair/upgrade a satelite that wasn't designed for repair? This system can get there and do it without involving humans at all. (Assuming your cost effective repair involves no humans)

            The Russian system is great when you know you will be going back. A supply ship to a space station is a good example. It is useless to something you didn't exp

            • Well actually no. If you read the DART site, the particular system being tested depends on passive reflectors... i.e., the satellite was designed for automatic docking.

              Could we develop a system for automated docking with a satellite that hadn't been designed for such? Possible, but a much harder problem, and frankly not worth the effort.

              The DART work will support the new Exploration Mission... and you can be assured that any system that is developed will require satellites designed for automatic docking

        • this is being funded. I can understand why the engineers and scientists are interested, because it's a hard problem. By why is this a priority for the people writing the budget? Are we expecting to do so many space rendezvous sometime inthe future that we have to have an automated system?

          I wonder if this isn't a step towards developing an antisatellite weapons system.
      • There's a big difference between a remotely controlled space craft and an autonomously controlled space craft. Progress is remote controlled. DART was fully autonomous.

        Even with a remote controlled space craft, the Russians almost took out MIR.
      • It must be incredibly hard, if NASA have trouble with it.

        Pet peeve time mode = ON

        When referring to an organization as a whole, it is a singular noun. In this usage, NASA is a singular noun, and therefore the sentence should read, "It must be incredibly hard, if NASA has trouble with it".

        Only when referring to the individuals with an organization is it a plural noun. Such a usage would be "Ford were in agreement on their decision to choose a new CEO". In that case you're obviously referring to more than
        • Freaking pedant.

          What is usually meant by this usage of the singular in English is something like:

          "If (those) NASA (guys) have trouble with it."

          Something that can usually be fully understood and comprehended by native English speakers.

          So I've either riled up a dedicated *pedant* or I have assisted in the education of someone who has English as a second (or third or n) language.

          • I'm sorry if you don't have a firm grasp of the English language. I'm here to help.

            These links may help you speak what is probably your primary language:

            http://www.nottingham.ac.uk/public-affairs/uon-st y le-book/singular-plural.htm [nottingham.ac.uk]

            http://alt-usage-english.org/intro_d.shtml#Groupno unssingularorpluralcompanyisvcompanyare [alt-usage-english.org]
            • actually its a good job you pointed it out or else I could have gone through my whole life meeting blank stares to such unintelligible phrases as 'to boldly go where no man has gone before'. I mean how can anyone extract sense from that jumble of words?

              Actually, I believe that language is defined by common usage; if people understand what is said (or written) then it works and is therefore, by definition, correct usage.

              Natural languages do not come from books (or websites).

              • Actually, I believe that language is defined by common usage; if people understand what is said (or written) then it works and is therefore, by definition, correct usage.

                Nice attempt at revising the definition of "correct usage". If the majority of people use incorrect grammar, it doesn't make that grammar any more correct, it only highlights the fact that the majority of people don't have a firm grasp of the language.

                Such reasoning reminds of the lame attempt at legitimizing street slang and calling it
    • If Hubble's big problem is with its gyros, why not dock an additional module with them inside. The gyros that keep something stable do not need to be inside it.

      Smarter still would be to attach an orbit-transfer vehicle to it to allow it to be serviced at the ISS, instead of sending up someone with a shuttle. The parts needed for the job could be sent on a Progress or that other ESA cargo vehicle I am too lazy to look up now and the ISS is a cash-drain ^H^H^H^H^H^H^H^H^H^H solution desperately seeking a pro
    • Why is this stuff considered so difficult. Artificial intelligence in areas like video games do things that are orders of magnitude more difficult.
    • 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.

      Totally autonomous isn't ready but that doesn't mean you need astronouts. What they should do is send up a robot that's controlled from the ground. It will attempt repair of the gyros and attach a deorbit package. If you're sending up a deorbit robot anyway, might as well at

  • Finding satellites (Score:3, Funny)

    by vandoravp ( 709954 ) on Saturday April 16, 2005 @11:19PM (#12259181) Homepage
    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*
  • NASA is copying Apple now?
  • "Despite failure of ultimate task, the craft was a success!"

    But seriously, is this that big of a deal? Haven't Russian supply ships been docking automatically for many years now? Is size of the target the only difference in this instance?

    • I do not believe a Soviet supply cargo ship (progress, perhaps) was entirely autonomous.

      And NASA is saying that they were able to accomplish some of the goals from this experiment. Yeah, I do agree that NASA's talking head could phrase it better..
      • Your belief is not required. The soviets created completely autonomous docking systems in the 80s that are still used today. The difference is that DART doesn't require active 2-way cooperation from the target.
      • The Progress ships are automated, but are very closely monitored on final station approach. An astronaut or ground control can take over the operation at the first sign of trouble. Linky. [nasa.gov] The station is also a very big target. The point of DART was to demonstrate automated rendezvous capability with a much smaller target. That it got within 300 feet is pretty darn good, IMHO.

        I know very little about the mission, but I'll take a wild guess here, the navigational systems probably need refining. It soun

  • I, for one . . . (Score:5, Funny)

    by Council ( 514577 ) <rmunroe@gmaPARISil.com minus city> on Saturday April 16, 2005 @11:23PM (#12259206) Homepage
    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.

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

      NORAD's new laser warning system [slashdot.org] has been successfully demonstrated in space after a terrorist DART satellite's attempt to enter the 300 feet "personal space bubble". The laser warning system was put into effect after all attempts to contact the DART satellite failed. "We knew the satellite was hostile when its only reply was 'beep beep beep' to our verbal warnings over emergency radio bands." says NORAD spok

    • The Pentagon wishes to not announce a successful test of its antirendezvous technology.
    • Sure, I know you were trying to make a joke and I'm sidetracking...

      It really does sound like the DART is designed for multiple uses - sure, there are good applications like deploying extra supplies to a manned system, or deploying extra batteries or fuel to a system that has the capability to use them, but that's not really a separate problem from what an ASAT weapon needs to do to park itself next to an enemy satellite and destroy it. And no, I really wasn't thinking of this as a lead-in to saying "Someb

  • Re: DART Succumbs to Fuel Problems (Score:5, Funny)

    by kabz ( 770151 ) on Saturday April 16, 2005 @11:24PM (#12259210) Homepage Journal
    Well, you can hardly blame NASA for leaving the thing a bit short...

    Gas is $2.35 a gallon in Houston !

  • Partial success... (Score:5, Funny)

    by gabecubbage ( 711618 ) on Saturday April 16, 2005 @11:24PM (#12259217)
    I consider my recent trip to the bathroom a partial success, too. After all, I SAW the toilet.
  • If main fails, use back-up. If back-up fails, switch to back-up back-up.

    If failure of back-up back-up, back-up back-up back-up must suffice to accomplish mission.

  • This NASA mission brought to you by the Department of Redundancy Department...

  • units again? (Score:2, Insightful)

    by jonbrewer ( 11894 ) *
    "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 u

    • 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.

      Ah. I see you subscribe to the myth that a units error has caused NASA problems in the past.

      It hasn't.

      MCO was lost because managment ignored steady indications of an increasing navigation error. (An easily correctable error has they authorized spending the mone

  • Russia (Score:1, Funny)

    by Anonymous Coward
    Give NASA another 20 years and they may finally have caught up with Russia.

  • Orbital not NASA (Score:3, Informative)

    by TornNight ( 524761 ) on Saturday April 16, 2005 @11:44PM (#12259298)
    Orbital Designed, Manufactured, and launched DART.
    It's mostly their fault.
    http://www.orbital.com/NewsInfo/MissionUpdates/dar t.html [orbital.com]
  • I for one welcome our new autonomous semi-successful satellite finding space-craft overlords!

  • The $110 million mission (Score:2, Funny)

    by Anonymous Coward
    For 11 hours of productivity. Go NASA!
    • 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)
  • x = "space station"
  • I don't care how strong a bloke's arm is, there comes a point in time when, no matter how hard he throws a dart, gravity is going to win. :P
  • let me guess, NASA screwed up the conversion between liters and gallons... ... the fuel tank was labeled in gallons, and was filled with the prescribed liters of fuel.

  • the Russians (Score:1, Informative)

    by Anonymous Coward
    The Russians have been doing this for years and years.

    But remember folks! Nothing counts as a first until the USA does it. The first in everything is always an American - unless you count all of the others.
  • target rendezvous target, a Pentagon satelite
    Can anyone say redundant? Can anyone say redundant?
    And WTF is a "satelite [reference.com] ?"
  • This is a big reason why we still need manned missions.
  • Or could this have been a partial success, because it was partially a test of a system to autonomously seek and destroy satillites?

    It was a pentagon satillite, after all...
  • They prob had it running windows for the os... I remember that windows 95 c had a warning about using it to opperate machinery and what not. All kidding aside...Partial success? hmm I think thats a case of 'glass is half empty- half full' and in my experience. There is win or loose no in between. LEt see, the football team that lost says "oh yea it was a partial win then we got our azzes kicked in the finaly half" Not that I like to use a football metaphore. so here is a better metaphore. "oops the nuclea

  • job loss? (Score:1, Interesting)

    by Anonymous Coward
    Funny, if I screw up at work and cost my company 100 million dollars, I will be fired and quite possibly find it hard to ever work in the industry again.

    When NASA scientists do it and waste 100 million dollars of taxpayer money that could be spent solving REAL problems here on earth, we just laugh it off and use the newspeak-esque term "limited success".

    When NASA crashed a probe into mars because they forgot to convert units from metric to imperial, *why* did the scientists get to keep their jobs like not

    • Re:job loss? (Score:1, Insightful)

      by Anonymous Coward
      I sure wish I had a job like that, where I could screw up in breaktaking magnitude and not have to answer for it to anybody.

      Perhaps if your job was as complex as building rockets and satellites, you would understand. When there is a failure, there are inquiries lasting months to determine what went wrong and how to prevent it from happening in the future. When you screw up, someone has to take the unwanted pickles off of their hamburger.

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