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SpaceX Looking For Help With "Landing" Video
Maddog Batty (112434) writes "SpaceX recently made the news by managing to soft land at sea the first stage of rocket used to launch its third supply mission to the International Space Station. Telemetry reported that it was able to hover for eight seconds above the sea before running out of fuel and falling horizontal. Unfortunately, due to stormy weather at the time, their support ship wasn't able to get to the "landing" spot at the time and the first stage wasn't recovered and is likely now on the sea bed. Video of the landing was produced and transmitted to an aeroplane but unfortunately it is rather corrupted. SpaceX have attempted to improve it but it isn't much better. They are now looking for help to improve it further."
I smell a Photoshop Friday theme...
Watching that video on YouTube, it'd be tough to clean up or reconstruct - there's a lot of information missing.
my, your, his/her/its, our, your, their
I'm, you're, he's/she's/it's, we're, you're, they're
I appreciate them looking for public help. It's a gesture of trust and openness usually not seen from either goverment or private corporations.
Though I suspect most the the video is beyond salvage.
how does something fall horizontally? some strange gravity out there.
If we had access to the telemetry as say an FBX or Alembic file, it'd be pretty trivial to produce a visual representation of what happened, using what little video can be deciphered....without that, I don't see how anything can be salvaged
Well, it was Raw until YouTube re-compressed the hell out of it. Seriously, I don't think you have any shot if you start off with this YouTube footage. If they really want help we need the actual raw bitstream. I/Q output from the receiver would be even better. Even better than that would be diversity receivers. Aren't those guys the rocket scientists?
It really doesn't in this case. It's clearly busted beyond repair. The raw stream does not have any damned I-frames that are salvageable, and the Youtube version accurately represents this fact.
Usually they are going up when they have a camera, and on a course which is accurate enough to point a dish at it to get a better signal. Even then the signal usually cuts out a bit.
#naabhaprzrag, #sverubfr-000, #agi-fcbafberq, negvpyr[pynff*=' negvpyr-ary-'] { qvfcynl: abar !vzcbegnag; }
Whatever happened to redundant/multiple video recordings, like you know, how we back up data? Failing that, a stronger signal wouldn't hurt surely?
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Errm, they did have a well planned means to evaluate success: telemetry data. Which they have good copies of. The video is just candy.
True, but we have out of band information. We know the video is shot continuously (no cuts between different camera angles or cuts in time), so the image data should be linear (as in not suddenly turning into another color or luminance value). We also know that it depicts one scene, so there is a strong covariance between the macroblocks.
Lemme take another look.
... until they post an analog recording of the telemetry. The bitstream *as decoded* is corrupted because of demodulation errors, and you can't reconstruct data that isn't there. If they have an analog recording, then analog filters can be applied to that in an attempt to create a cleaner input signal to the demodulator stage. An analogy: They have taken a picture of a page of text, rather out of focus and dark, and used OCR software on it. All they are giving us is the output of the OCR software. We need to see the original picture so we can apply better filtering/contrast adjustments to it before attempting pattern recognition.
You seem a little harsh on them.
Recovery of the booster would have been nice for investigation, but it was never intended to be flown again and was never the stated goal. The goal for that mission was a controlled descent and touch down on the ocean, which they accomplished. A 'soft-recover' wasn't the term that they were using.
This goal needed to be reached so that Range Safety at the launch pad can determine that SpaceX can reliably put a rocket down within a mile or so of a target. The next launch - in the next week or so - will attempt to land in the ocean much closer to the launch facility.
The technical difficulties of a soft landing are considerable given the hardware that they've got. With the weight of the empty booster, they can't throttle the engines back far enough to hover. So they fall towards the surface and at the right moment fire the engines to reach a computed zero velocity at touchdown. Doing this with gusty 30-40 knot winds on the surface is tough. 'Landing' on a continuously-undulating surface where there is no consistent level is tougher.
And yes, parts of this have been done before. Sure, there's open-source avionics stacks that can do this thing no problemo. But a controlled return of the first stage of a liquid fuel rocket has never been done before, and this kind of work has most certainly never been done for the relatively tiny amount of money that SpaceX has been spending. *That* is the thing that's getting tongues wagging.
You are in a twisty maze of processor lines, all alike.
There is a lot of hype here.
The point of this test was never to recover the first stage.
That was a tertiary goal, absolutely, but it wasn't the primary objective of this test. Even if they had recovered it, they had absolutely no intentions of reusing this stage, since refurbishing a stage that's been exposed to salt water is more trouble than it's worth. It would take an estimated two months to get a water recovered stage ready for flight again.
SpaceX wanted to see if they could null out the rotation rate during descent to prevent another engine flame-out, successfully deploy the landing legs, have it stabilize it's descent rate, and finally hover over the surface before gently setting down. The real recoveries are only going to happen when they start landing these things on solid ground.
Seriously, land in a desert or something similar. Much easier to recover protected data storage units. If you can't hit the landing spot of a massive dessert, theres no way anyones going to let them land on a landing pad.
Maybe they should have transmitted to an airplane instead?
English... learn it some time.
http://blog.nexusuk.org
=Their experimental task, get the 1st stage to 0 velocity at 0 m so it would softly settle on the ocean was a success.
Most falling objects tend to get to about 0 velocity at 0m :)
Anyway, I can't help but think that it would've been smart to eject a floating lump of flash memory before the rocket sank rather than relying on a live radio link.
http://blog.nexusuk.org
Click the "looking for help" link and scroll to the bottom.
try "computer, enhance ..."
They should just send frame by frame to the CSI guys and they will than click ----enhance----, DUH.
They claim it was successfully able to return to the surface and perform a soft "landing". Which it did...and it did so in thoroughly bad weather, in high winds and on heavy waves instead of solid ground. Their mission objectives were met completely the moment the rocket cut its engine and started tipping over. Actually fishing the thing out of the ocean intact would have been a nice bonus, but it has nothing to do with their actual plans for recovery and reuse...and the only reason it didn't happen is that nobody wanted to attempt it during the storm.
It's entirely possible it actually was recorded in some buoyant piece of hardware, just in case...but it'd probably have been intended to be picked up out of the debris field of a descent failure in fair weather. Where would it have ended up after the storm tore the rocket apart?
They could engineer a ruggedized black box with a tracking beacon and deployment system...but that's a bit much when they've only got a few water landings left, and those are unlikely to happen in storms. I think they were more concerned with making the rocket land itself.
So they try to transmit raw MPEG without any FEC coding?
I guess they could have been more successfull by beaming analog CVBS instead.
Telecommunications has improved since the 80s, you know.
And this is the best PR stunt they could make instead of just tossing it, recovering that video has next to no practical value for SpaceX. A little geek challenge while they wait for the next test closer to land that'll probably be filmed from many angles.
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Well, yeah, the video is primarily of PR and posterity value... But is there a problem with that?