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DART Succumbs to Fuel Problems
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.'"
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?
Orbital Designed, Manufactured, and launched DART.r t.html
It's mostly their fault.
http://www.orbital.com/NewsInfo/MissionUpdates/da
Hey watch this! Splat...
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).
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.
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.
"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.
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/