Author Topic: SpaceX's Autonomous Spaceport Drone Ship Updates and Discussion Thread 3  (Read 1424048 times)

Offline MarekCyzio

We can assume that one of reasons SpaceX is building automated rocket mounting robot is to reduce time between barge landing and rocket unload (of course main reason is to eliminate potentially very risky task of catching sliding rocket). So it would make sense to perform more processing steps at the barge - at the minimum leg folding. I wonder if this is what SpaceX plans...
 
Edit - typo

Sent from my iPhone using Tapatalk
« Last Edit: 02/25/2017 02:12 pm by MarekCyzio »

Offline Alastor

  • Full Member
  • ***
  • Posts: 380
  • Liked: 306
  • Likes Given: 573
As far as we understand it right now, the plan would be to grab the rocket by the legs, and we have no indication that they would plan to be able to fold the legs without having to remove them.

The second point may be justified by both safety and processing reasons.
Safety because you don't want risking the legs to fold upon landing. So if they are simply designed to not fold, it's safer. Processing, because I suspect that they at least have to change the crush core everytime, so it may be easier to do with the legs removed.

Now if they grab the rocket by its feet as they seem to be about to do, it would not be possible right now to fole or remove the legs in situ.

I guess a first indication of that happening would be if we see a holding stand and crane appearing on the droneship. So I would say not in the nearfuture at least, and I'm not convinced that it would be really doable.

Offline rpapo

To have a sufficiently tall crane on the barge, and a stand, I would think the barge would have to get much, much larger.  And trying to manage such a large crane while the barge is pitching and rolling with the waves would be dicey, at best.  So unless SpaceX wants to recycle a full-sized aircraft carrier or an oil super-tanker to recover stages, I would think they're better off simply doing what it appears they are doing: coming up with a safer, more automated way to secure the stage.  There's no pressing need to do more than that, at least that I am aware of.

If they absolutely had to put in something to secure the stage in an upright position and remove the legs before getting back to port, they could always try to do something like the Soyuz TLE in reverse, with multiple arms reaching up from below to enclose the stage like a Venus Flytrap with three or four petals.  Such a Goldberg device would probably be safer than installing a crane on the barge.

It would still require a bigger barge, though, and it probably wouldn't be worth the expense.
« Last Edit: 02/25/2017 03:58 pm by rpapo »
Following the space program since before Apollo 8.

Offline RonM

  • Senior Member
  • *****
  • Posts: 3340
  • Atlanta, Georgia USA
  • Liked: 2231
  • Likes Given: 1584
Why SpaceX would want to remove the legs at sea? it may save a little time, but it's simpler to hold down the booster by the legs than move it to a mount on the ship.

Offline cscott

  • Senior Member
  • *****
  • Posts: 3471
  • Liked: 2867
  • Likes Given: 726
We don't actually "know" that the plan is to grab the feet.  The "Roomba garage" could be for videography drones or fire-fighting robots or who knows what else.
« Last Edit: 02/25/2017 04:52 pm by cscott »

Offline dorkmo

  • Full Member
  • ****
  • Posts: 710
  • Liked: 338
  • Likes Given: 848
We don't actually "know" that the plan is to grab the feet.  The "Roomba garage" could be for videography drones or fire-fighting robots or who knows what else.

or just old fashion aircraft jack storage

Offline Alastor

  • Full Member
  • ***
  • Posts: 380
  • Liked: 306
  • Likes Given: 573
We don't actually "know" that the plan is to grab the feet.  The "Roomba garage" could be for videography drones or fire-fighting robots or who knows what else.

That's why I used "As far as we understand it", and not "As far as we know".
That said, grabbing it by its feet is quicker, safer and simpler (and thus even safer) that what is currently used.

It makes a lot of sense, and I'm actualy surprised that they didn't use it since the very beginning, since the first landings were arguably the most dangerous ones, given that they were more experimental.

It is the leading theory, there is no indication that they are doing something else, and I am myself fairly certain that's what they are doing, even though I have no definite proof.
Now once that's said, feel free to disagree, but I believe I make a pretty good case ! :-)

Offline Lar

  • Fan boy at large
  • Global Moderator
  • Senior Member
  • *****
  • Posts: 13463
  • Saw Gemini live on TV
  • A large LEGO storage facility ... in Michigan
  • Liked: 11864
  • Likes Given: 11086
Why invest in foot welding robots before you know whether there will be any feet to even weld. SpaceX is incremental. Each time, they improve something.

Watch and wait.
"I think it would be great to be born on Earth and to die on Mars. Just hopefully not at the point of impact." -Elon Musk
"We're a little bit like the dog who caught the bus" - Musk after CRS-8 S1 successfully landed on ASDS OCISLY

Online Johnnyhinbos

  • Senior Member
  • *****
  • Posts: 3863
  • Boston, MA
  • Liked: 8095
  • Likes Given: 943
Okay, so here's my unasked for, un-rooted in firsthand knowledge, prediction.

Based on what the Roadie has alluded, and on what's been shown by the excellent spy photos around the ASDS, and on a general observation of the recovery process, here's my WAG on what's being developed...

Deck ops on the ASDS are dangerous and open SpaceX up for all kinds of liability (my job is to mitigate liability on a relatively dangerous workplace activity, so I'm sensitive to that). So I suggest they're developing a bot (four per ASDS) that has a jack stand top that can autonomously navigate out to under a landed booster, attach to a hold down point and spot weld itself to the deck after a positive capture of the hold down point. Four of these effectively replace the function of the jacks and ratchet chains humans currently need to install under a landed booster. No crane (way too impractical on the barge), no lifting it up into the stands you see in port to remove the legs, and no attaching anything to the legs themselves. The legs are a liability whereas the hold down points on the octoweb are designed to take strain.

This is just to allow an autonomous securing of the stage until its towed to port to take the human out of the loop.

But, as Lar said, time will tell...
« Last Edit: 02/26/2017 01:53 am by Johnnyhinbos »
John Hanzl. Author, action / adventure www.johnhanzl.com

Offline cscott

  • Senior Member
  • *****
  • Posts: 3471
  • Liked: 2867
  • Likes Given: 726
How high above the deck are the hold down points?

Offline old_sellsword

  • Full Member
  • ****
  • Posts: 632
  • Liked: 531
  • Likes Given: 470
How high above the deck are the hold down points?

About ten feet. It's over five feet from the ground to the bottom of the engine bells, and then I estimated the rest based on this picture.
« Last Edit: 02/26/2017 03:58 am by old_sellsword »

Offline meekGee

  • Senior Member
  • *****
  • Posts: 14158
  • N. California
  • Liked: 14046
  • Likes Given: 1392
Okay, so here's my unasked for, un-rooted in firsthand knowledge, prediction.

Based on what the Roadie has alluded, and on what's been shown by the excellent spy photos around the ASDS, and on a general observation of the recovery process, here's my WAG on what's being developed...

Deck ops on the ASDS are dangerous and open SpaceX up for all kinds of liability (my job is to mitigate liability on a relatively dangerous workplace activity, so I'm sensitive to that). So I suggest they're developing a bot (four per ASDS) that has a jack stand top that can autonomously navigate out to under a landed booster, attach to a hold down point and spot weld itself to the deck after a positive capture of the hold down point. Four of these effectively replace the function of the jacks and ratchet chains humans currently need to install under a landed booster. No crane (way too impractical on the barge), no lifting it up into the stands you see in port to remove the legs, and no attaching anything to the legs themselves. The legs are a liability whereas the hold down points on the octoweb are designed to take strain.

This is just to allow an autonomous securing of the stage until its towed to port to take the human out of the loop.

But, as Lar said, time will tell...

If you're right, and the intent is to catch the thrust structure (or hold-downs) then you need a single large robot (3.7m diameter) since everything is rigid.  It drives underneath, grabs the holddowns, and welds itself down.  I like that a lot.

However, I'm voting for "catch it be the legs" until the crew can board.  That'll be a plenty safe condition for them to operate on the rocket. Since the legs are not rigid, (and since you won't build a 20m robot) then in that case I'd vote for 4 individual robots.

I'll be happy either way, assuming always we are talking about a tie-down robot of some sort.

(And I 100% agree with the rationale.  Boarding a barge with an unsecured load like this is just waiting for an accident)
ABCD - Always Be Counting Down

Offline marksmit

  • Member
  • Posts: 9
  • Leiden, The Netherlands
  • Liked: 6
  • Likes Given: 212
A whole bunch of high quality new photos of OCISLY of yesterday: https://imgur.com/gallery/TDVSV
« Last Edit: 02/26/2017 09:56 am by marksmit »

Online Herb Schaltegger

Excellent photos. Looks like they've built a small platform area between the top of the existing blast deflector and the newly-elevated equipment container, and built a new section of blast deflector plates on that elevated platform to protect the exposed top half of the container. Whatever is going into the "garage area" below the new platform and container behind the existing blast wall will be pretty well protected.

Still not convinced it's going to be  "Roomba welders" or any such Rube Goldberg contraption, but it will be interesting to watch.
Ad astra per aspirin ...

Offline meekGee

  • Senior Member
  • *****
  • Posts: 14158
  • N. California
  • Liked: 14046
  • Likes Given: 1392
Excellent photos. Looks like they've built a small platform area between the top of the existing blast deflector and the newly-elevated equipment container, and built a new section of blast deflector plates on that elevated platform to protect the exposed top half of the container. Whatever is going into the "garage area" below the new platform and container behind the existing blast wall will be pretty well protected.

Still not convinced it's going to be  "Roomba welders" or any such Rube Goldberg contraption, but it will be interesting to watch.
The Roomba take offense at being labeled Rube Goldberg-esque
ABCD - Always Be Counting Down

Offline matthewkantar

  • Senior Member
  • *****
  • Posts: 2075
  • Liked: 2506
  • Likes Given: 2211
They had a little man lift on board for early landing attempts but it got toasted in a crash. I don't think they have had one aboard since. Not sure what they were planning on using the rig for, but It seems likely the purpose of the new garage is to protect it. Weldbas would be cool though.

Matthew

Offline MarekCyzio

Garage is ready

Offline vanoord

  • Full Member
  • ****
  • Posts: 693
  • Liked: 450
  • Likes Given: 106
There are several big welded-on eyes / attachment points on both the refitted section of blast wall and the flat deck above it.  I wonder what they're for?

Looking at that image, it might just be that they want to store something like decent-sized welding sets on board and be able to lift up a section of blast wall and roll them out.

We sometimes look for complication, forgetting that a lot of what SpaceX does is simple (admittedly well-executed) rather than intricate to the extreme.

Offline Davp99

  • Full Member
  • **
  • Posts: 232
  • Fall River, MA
  • Liked: 50
  • Likes Given: 263
Aye Skipper, Open up the "Shamrock Garage"..
You Only Live Twice

Offline CJ

  • Full Member
  • ****
  • Posts: 1302
  • Liked: 1282
  • Likes Given: 540
After a look at the pics (Thanks!!!!!!!!), I now agree with those who say something is definitely going on regarding the blast wall and that new space under a container.

I'm dubious that they are making the blast wall open upward though; that would be hard due to the weight of it. My guess is either sliding to the side, or hinged panels opening outward.

My current prime suspect for a resident of the new space is a cherry picker, but that's just a wild guess. 

Tags:
 

Advertisement NovaTech
Advertisement Northrop Grumman
Advertisement
Advertisement Margaritaville Beach Resort South Padre Island
Advertisement Brady Kenniston
Advertisement NextSpaceflight
Advertisement Nathan Barker Photography
1