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.'"

Comments

They should do this mission again

[TheKidWho]

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.

Lessons learned?

[helioquake]

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?

[TheKidWho]

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?

[Anonymous Coward]

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).

Re:Lessons learned?

[tsotha]

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.

Re:Lessons learned?

[myowntrueself]

"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.

I, for one . . .

[Council]

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.

Re: DART Succumbs to Fuel Problems

[kabz]

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

Gas is $2.35 a gallon in Houston !

Partial success...

[gabecubbage]

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

Re: DART Succumbs to Fuel Problems

[dgatwood]

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.