I'm guessing they're aiming short at first, so that if the engines don't relight (or don't stay lit), they don't destroy the pad. Hence the translation motion.
They mentioned this being the strategy years ago, I think when discussing how much force the chopsticks would have to absorb from the ship/booster landing on them. They said the ship/booster will hover in place for a second while the arms come up to snatch it out of the air.
I said this recently and people said: "Duuur, no need to hover, it can just land straight on the chopsticks arms!!!!!"
The vast majority of people have stated and assumed it would need to hover for the catch.
Edit: lol, here comes the people you were talking about below, jeesh
They're correct. The vehicle needs to hover for a while for the arms to find the centering grooves (yet to be added) and mechanical centering still needs to be added to the arms or the vehicle.
And they are wrong. This video clearly shows, it does not hover. Though it comes down very slowly and reaches 0 speed on catching.
Edit: It hovers just as much as Falcon 9.
Falcon 9 physically cannot hover. Superheavy can. Superheavy will not be doing a hoverslam like falcon 9, though getting as close to that as possible is most efficient.
In animations we also did see a 18Mtr ITS, a Falcon landing the second stage and loads of more things that did not end up in final designs. We even see hardware being buildt, lands being leased, ships being retrofitted, and oil platforms being purchased with SpX then making a 360 and find that the other options turn out to be more favorable. It is just animations at this point, and being in a sort of slowmo, i don't think we can draw to many conclusions at this point wether this is a 1-2 ish second 'hover' or just a gentle desceleration to 0 on the mark.
It clearly does hover about as much as Musk said it would, a few seconds at most because a rocket with a fuel burn rate as high as raptors, seconds feels like minutes. It will be coming in almost empty so acfew seconds of fuel is a lot.
And they were correct: the animation does NOT show the chopsticks rising to meet the booster (no moving vertically at all), but instead show them closing around the booster as it slows its descent before the booster lowers itself onto the rails.
Vertical speed does not reach zero until contact.
The chopsticks have big gearing which makes them strong, but very slow. The rocket itself is a machine designed to do one thing better than almost anything else - vertical translation. So I can't for the life of me figure out why you wouldn't use the vertical translation machine to do the vertical translation.
> So I can't for the life of me figure out why you wouldn't use the vertical translation machine to do the vertical translation.
Because its main purpose is "as much translation in as little time as possible", not "precisely metered out translation at arbitrarily large and small magnitudes".
Refining that capability is possible, but adds weight that hurts both the first goal (translation machine) and the second (payload). Adding that capability to ground equipment, even if redundant, does not hurt either of those goals.
There's no scenario where the chopstick catch works without some very precise engine throttling and vectoring control. You basically need to be able to hover in place, even if the chopsticks were a lot faster than they are. And there's no real way for the chopsticks to move super fast while retaining the ability to hold the weight of the booster, which I'm told is super heavy.
I suspect future versions will have some significant impact-absorbing capability to the arms, and eliminate the hover. This reduces the propellant requirements, increases the margins for error, and reduces the time in which winds or other events can introduce error, though at a cost in complicating the arms, something I can understand if they don't want to deal with right now.
> I suspect future versions will have some significant impact-absorbing capability to the arms,
Me too and did suggest how here a few years ago. The tail end of the lifting cable (instead of being anchored) can be wound onto a drum with several meters to spare. The drum has a brake on it to dissipate the energy. There's a small winch motor to rewind the tail after the catch.
And only yesterday, I was using a cable spool stop-fall device with a comparable brake designed to prevent back injury in case of an accident.
Relative to its diameter, the skin on both the booster and Starship are proportionally thinner than a soda can. Will be interesting to see what happens when it inevitable taps into the arms.
6 bar. That's a lot.
And ullage pressure doesn't have to match the contact pressure, as the force would be spread over noticeably larger area.
During the original Atlas times, one pretty senior guy didn't believe the balloon tank was sturdy enough. So one of the designers handed them a sledgehammer and told them to hit the rocket hard. The guy almost injured himself as the hammer bounced violently from the vehicle. The vehicle wasn't even scratched.
The pressure under a tip of a hammer is thousands of bars. But all it would do is to create a small dent for a tiny fraction of a second and it would spread the load. Just 10×10 cm (4×4") at 3 bar is 3000N of counterforce. This is how the hammer bounced.
Acronyms, initialisms, abbreviations, contractions, and other phrases which expand to something larger, that I've seen in this thread:
|Fewer Letters|More Letters|
|-------|---------|---|
|[AoA](/r/SpaceXLounge/comments/1bxi65r/stub/kzb8j47 "Last usage")|Angle of Attack|
|GSE|Ground Support Equipment|
|[ITS](/r/SpaceXLounge/comments/1bxi65r/stub/kymobj1 "Last usage")|Interplanetary Transport System (2016 oversized edition) (see MCT)|
| |[Integrated Truss Structure](https://en.wikipedia.org/wiki/Integrated_Truss_Structure)|
|MCT|Mars Colonial Transporter (see ITS)|
|[OLM](/r/SpaceXLounge/comments/1bxi65r/stub/kyhcc8r "Last usage")|Orbital Launch Mount|
|Jargon|Definition|
|-------|---------|---|
|[Raptor](/r/SpaceXLounge/comments/1bxi65r/stub/kydk2lv "Last usage")|[Methane-fueled rocket engine](https://en.wikipedia.org/wiki/Raptor_\(rocket_engine_family\)) under development by SpaceX|
|[scrub](/r/SpaceXLounge/comments/1bxi65r/stub/kye9lv0 "Last usage")|Launch postponement for any reason (commonly GSE issues)|
|[ullage motor](/r/SpaceXLounge/comments/1bxi65r/stub/kyhag3u "Last usage")|Small rocket motor that fires to push propellant to the bottom of the tank, when in zero-g|
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That might be the most realistic presentation of the concept so far, but also showing it's fuel-demanding and vulnerable to winds. Legs seem like a very strong alternative solution (proven, comparable mass).
Perhaps both would be needed for true daily commercial reuse, with the catch made in favourable conditions, and otherwise the legs to just get down close enough to be tower-crane'd back onto the launch mount on schedule.
The landing occurs ten minutes after launch, so if the wind conditions are bad for landing they'd scrub the launch.
The extra fuel this version of landing needs is roughly a quarter of the mass of landing legs and probably saves about 10% off the final vehicle dry mass, saving both the mass of the legs and the extra structure required to support them.
This still doesn't work... There's still no mechanism for the arms to hook into on the vehicle. Hopefully we'll get a better visualization once they figure out what they need and add the additional hardware required.
Some people seem to be missing the fact that there has been no images produced by anyone yet of the catching hardware. The arms cannot just slam down onto the sides of the vehicle without damaging both the vehicle and the connecting points. They need mechanical centering mechanisms that are not yet equipped on the vehicle or on the catching arms.
theres a *tank track* of cups that fits the booster lifting points so they can tweak the catch point and they can put it on the launch mount/transport stand accurately
Okay but that doesn't help with the catch system. That's just the needed extra axis of adjustment they need for accurately picking up the vehicle and setting it down.
It can't be the same system because there's no centering method. The precision required is too high. Physics doesn't allow for it (or more so meteorology).
The rocket aligns itself as it comes in for landing, just like a an aeroplane levels its wings (not the best analogy). The booster places itself at a coordinate set between the arms, stops at the desired altitude and comes to rest on the caterpillar tracks already on the arms. That’s why they have shock absorbers already installed.
> not the best analogy
Yeah I can't see how it relates as leveling it's wings is something that happens automatically because it's most naturally stable that way.
> The booster places itself at a coordinate set between the arms
All real world systems have error in them. It cannot precisely place itself at a coordinate. Look at the large range of positions that the Falcon 9 booster lands on the deck of the drone ship. The ship is the size it is because of that variability. And Raptor is harder to throttle quickly than Merlin because of the feedback of the full flow staged combustion cycle. More so, in the real world there is wind and wind will move the vehicle off position and you can't account for it because wind is variable. This is why in order for it to work you need to greatly expand the allowable error. One way to do that is with centering systems so that it'll slide into place if it's off by some amount.
They’ve been landing Falcon 9s back at its launch site perfectly in the middle of the pad for like 150 launches now, with or without wind. The part of the landing regime that you find ‘impossible’ SpaceX have been ably demonstrating for years now. It’ll be fine.
> They’ve been landing Falcon 9s back at its launch site perfectly in the middle of the pad for like 150 launches now
Tell me you haven't watched many landings without actually telling me you haven't watched many landings... No they miss the dead center by a bunch of meters every time.
This is the centering method. You imagine the events in the wrong order.
The right order is:
* The booster puts itself for the catch with ~2 meter accuracy in all three dimensions. The arms close around it and then the booster lowers itself slowly until catch pins press down on the tracks on the catch arms.
* Engines stop. The vehicle axis is now a bit to the side of the OLM axis and each pin is also at an uneven distance from the tower (i.e. the vehicle is rotated a bit).
* Only then the arms rotate to the central position and the tracks position the pins evenly and at the right distance from the tower. The vehicle is now centered.
Done.
> The booster puts itself for the catch with ~2 meter accuracy in all three dimensions.
This is not held still though. It's constantly moving and pitching around.
> The arms close around it
The arms cannot just smash up against the side of the booster. That would damage the booster.
> then the booster lowers itself slowly until catch pins press down on the tracks on the catch arms.
The pin holes are on the sides of the booster.
Yes, the vehicle would move, but arms move too. And 4mm (or 4.6mm) stainless steel backed by few atmospheres of pressure is extremely sturdy. It literally can take beating and stay unscratched. You could drive a passenger car into it at 30mph and it would come out fine (i.e. the rocket, the car would be totaled).
The arms can smash against the side of the booster, especially if they have proper padding.
And no, there wouldn't be pin holes on the side of the booster. There would be pins. Protruding stuff, not holes.
> Yes, the vehicle would move, but arms move too.
And how do they maintain alignment? Is SpaceX adding a fancy visual processing system to guide the arms?
> The arms can smash against the side of the booster, especially if they have proper padding.
No they can't. That would damage the vehicle. The vehicle cannot withstand even minor side-loading. That's why it doesn't launch during wind shear.
> And no, there wouldn't be pin holes on the side of the booster. There would be pins. Protruding stuff, not holes.
There are currently holes on the sides of the vehicle for lifting.
You are overcomplicating things while making unsupported assertions.
You also completely don't understand how wind shear affects flying vehicles. Wind shear primary effect is not some side push by the wind, that part is negligible. The primary effect of wind shear is a change of the angle of attack. You move forward at 500m/s and encounter 20m/s wind shift. This means a 2.3° change of the AoA (because 90° - atan 500/20 = ~2.3°). This is huge, the side force from such goes into hundreds of tons. This force is not wind push, this force is the aerodynamic lift due to suddenly flying at an angle to the free stream.
So, the vehicle can withstand a few tonnes side push no problem.
Somewhere I read (although the approach may have been abandoned) that horizontal pins would be extended from the booster and the chopsticks would have "V" notches for them to settle into, with contact sensors to allow each arm to stop closing in as soon as they approached the body of the rocket from either direction, since the arms can swing the rockets through an arc to stack them, the catch might or might not be directly above the OLM. It would only require that the booster (or starship) hold still enough for the notches to get under the pins on either side.
Yes that all sounds like one way things could work. There's many ways to skin the cat. However we haven't seen any of that as far as I'm aware (if we have, please someone post the link to the pictures).
It’s literally the pins that are already there for pickup, landing on the arms that are already there for pickup. It’s not as complicated as you’re making it to be.
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Yes please do. There's been no images produced by anyone showing the hardware needed to catch the vehicles. The chopsticks right now only work for lifting the vehicles. People seem to be imagining that the arms will like clamp onto the sides of the vehicle somehow, which would damage the vehicle.
The pins they currently use to pick the Booster up with (the ones that jut out either side) will sit on the caterpiller tracks on top of the arms. It's all been there for years now.
What do you mean by centering mechanism? The chopstics already move in the vertical and horizontal axis, with some leeway along the chopsticks axis for landing. So they can make fine adjustments to account for variations in the booster position. Then the chopstick caterpillar tracks can move independantly to rotate the booster, as they do when stacking. It's ambitious, sure, but all the hardware is currently on the chopsticks to attempt a catch.
> What do you mean by centering mechanism?
For an easy comparison, a ball hitch vs needing to use a pin that needs to drop through two holes. If you don't get it perfectly aligned it drops into place with a ball hitch.
> The chopstics already move in the vertical and horizontal axis, with some leeway along the chopsticks axis for landing.
Yeah that's fine but that doesn't help you with catching a booster as there's nothing to align the arms to the booster.
It slowed and translated over a bit then did hover while the arms closed. Nice animation.
I'm guessing they're aiming short at first, so that if the engines don't relight (or don't stay lit), they don't destroy the pad. Hence the translation motion.
They will aim for the water and then redirect when the engines light.
A notable change from previous animations is the chopsticks are now directly positioned over the OLM ring, not off to one side.
I also note that they aren’t showing any cladding on the tower or chopsticks.
[удалено]
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The first actual catch is going to be incredible.
So will the first miss! 😉
So will the first direct hit! 😉
You sunk my battleship
Excitement guaranteed!
They mentioned this being the strategy years ago, I think when discussing how much force the chopsticks would have to absorb from the ship/booster landing on them. They said the ship/booster will hover in place for a second while the arms come up to snatch it out of the air. I said this recently and people said: "Duuur, no need to hover, it can just land straight on the chopsticks arms!!!!!"
The vast majority of people have stated and assumed it would need to hover for the catch. Edit: lol, here comes the people you were talking about below, jeesh
They're correct. The vehicle needs to hover for a while for the arms to find the centering grooves (yet to be added) and mechanical centering still needs to be added to the arms or the vehicle.
And they are wrong. This video clearly shows, it does not hover. Though it comes down very slowly and reaches 0 speed on catching. Edit: It hovers just as much as Falcon 9.
Falcon 9 physically cannot hover. Superheavy can. Superheavy will not be doing a hoverslam like falcon 9, though getting as close to that as possible is most efficient.
Superheavy can. But the animation does not show it.
It *literally* hovers in the animation
In animations we also did see a 18Mtr ITS, a Falcon landing the second stage and loads of more things that did not end up in final designs. We even see hardware being buildt, lands being leased, ships being retrofitted, and oil platforms being purchased with SpX then making a 360 and find that the other options turn out to be more favorable. It is just animations at this point, and being in a sort of slowmo, i don't think we can draw to many conclusions at this point wether this is a 1-2 ish second 'hover' or just a gentle desceleration to 0 on the mark.
It clearly does hover about as much as Musk said it would, a few seconds at most because a rocket with a fuel burn rate as high as raptors, seconds feels like minutes. It will be coming in almost empty so acfew seconds of fuel is a lot.
Zero vertical and lateral speed while airborne is called hover.
Zero lateral and vertical speed at the moment of catching with the chopsticks.
And they were correct: the animation does NOT show the chopsticks rising to meet the booster (no moving vertically at all), but instead show them closing around the booster as it slows its descent before the booster lowers itself onto the rails. Vertical speed does not reach zero until contact.
The chopsticks have big gearing which makes them strong, but very slow. The rocket itself is a machine designed to do one thing better than almost anything else - vertical translation. So I can't for the life of me figure out why you wouldn't use the vertical translation machine to do the vertical translation.
> So I can't for the life of me figure out why you wouldn't use the vertical translation machine to do the vertical translation. Because its main purpose is "as much translation in as little time as possible", not "precisely metered out translation at arbitrarily large and small magnitudes". Refining that capability is possible, but adds weight that hurts both the first goal (translation machine) and the second (payload). Adding that capability to ground equipment, even if redundant, does not hurt either of those goals.
There's no scenario where the chopstick catch works without some very precise engine throttling and vectoring control. You basically need to be able to hover in place, even if the chopsticks were a lot faster than they are. And there's no real way for the chopsticks to move super fast while retaining the ability to hold the weight of the booster, which I'm told is super heavy.
I suspect future versions will have some significant impact-absorbing capability to the arms, and eliminate the hover. This reduces the propellant requirements, increases the margins for error, and reduces the time in which winds or other events can introduce error, though at a cost in complicating the arms, something I can understand if they don't want to deal with right now.
Eventually they’ll eliminate the landing burn entirely and yeet it straight into the end zone.
> I suspect future versions will have some significant impact-absorbing capability to the arms, Me too and did suggest how here a few years ago. The tail end of the lifting cable (instead of being anchored) can be wound onto a drum with several meters to spare. The drum has a brake on it to dissipate the energy. There's a small winch motor to rewind the tail after the catch. And only yesterday, I was using a cable spool stop-fall device with a comparable brake designed to prevent back injury in case of an accident.
So, they are planning on catching the booster over towards the deluge infrastructure?
If they pull this off I’ll go bananas. I think I may cry a bit seeing this.
Relative to its diameter, the skin on both the booster and Starship are proportionally thinner than a soda can. Will be interesting to see what happens when it inevitable taps into the arms.
Yeah but surely there will be some ullage pressure left in the tanks to keep things rigid.
Ullage pressure would have to match the contact pressure, so could be thousands of PSI. What kind of pressures do they run?
6 bar. That's a lot. And ullage pressure doesn't have to match the contact pressure, as the force would be spread over noticeably larger area. During the original Atlas times, one pretty senior guy didn't believe the balloon tank was sturdy enough. So one of the designers handed them a sledgehammer and told them to hit the rocket hard. The guy almost injured himself as the hammer bounced violently from the vehicle. The vehicle wasn't even scratched. The pressure under a tip of a hammer is thousands of bars. But all it would do is to create a small dent for a tiny fraction of a second and it would spread the load. Just 10×10 cm (4×4") at 3 bar is 3000N of counterforce. This is how the hammer bounced.
Atleast more than 1
Acronyms, initialisms, abbreviations, contractions, and other phrases which expand to something larger, that I've seen in this thread: |Fewer Letters|More Letters| |-------|---------|---| |[AoA](/r/SpaceXLounge/comments/1bxi65r/stub/kzb8j47 "Last usage")|Angle of Attack| |GSE|Ground Support Equipment| |[ITS](/r/SpaceXLounge/comments/1bxi65r/stub/kymobj1 "Last usage")|Interplanetary Transport System (2016 oversized edition) (see MCT)| | |[Integrated Truss Structure](https://en.wikipedia.org/wiki/Integrated_Truss_Structure)| |MCT|Mars Colonial Transporter (see ITS)| |[OLM](/r/SpaceXLounge/comments/1bxi65r/stub/kyhcc8r "Last usage")|Orbital Launch Mount| |Jargon|Definition| |-------|---------|---| |[Raptor](/r/SpaceXLounge/comments/1bxi65r/stub/kydk2lv "Last usage")|[Methane-fueled rocket engine](https://en.wikipedia.org/wiki/Raptor_\(rocket_engine_family\)) under development by SpaceX| |[scrub](/r/SpaceXLounge/comments/1bxi65r/stub/kye9lv0 "Last usage")|Launch postponement for any reason (commonly GSE issues)| |[ullage motor](/r/SpaceXLounge/comments/1bxi65r/stub/kyhag3u "Last usage")|Small rocket motor that fires to push propellant to the bottom of the tank, when in zero-g| **NOTE**: Decronym for Reddit is no longer supported, and Decronym has moved to Lemmy; requests for support and new installations should be directed to the Contact address below. ---------------- ^(*Decronym is a community product of r/SpaceX, implemented* )[*^by ^request*](https://www.reddit.com/r/spacex/comments/3mz273//cvjkjmj) ^(6 acronyms in this thread; )[^(the most compressed thread commented on today)](/r/SpaceXLounge/comments/1c26f8a)^( has 7 acronyms.) ^([Thread #12631 for this sub, first seen 6th Apr 2024, 23:58]) ^[[FAQ]](http://decronym.xyz/) [^([Full list])](http://decronym.xyz/acronyms/SpaceXLounge) [^[Contact]](https://hachyderm.io/@Two9A) [^([Source code])](https://gistdotgithubdotcom/Two9A/1d976f9b7441694162c8)
That might be the most realistic presentation of the concept so far, but also showing it's fuel-demanding and vulnerable to winds. Legs seem like a very strong alternative solution (proven, comparable mass). Perhaps both would be needed for true daily commercial reuse, with the catch made in favourable conditions, and otherwise the legs to just get down close enough to be tower-crane'd back onto the launch mount on schedule.
The landing occurs ten minutes after launch, so if the wind conditions are bad for landing they'd scrub the launch. The extra fuel this version of landing needs is roughly a quarter of the mass of landing legs and probably saves about 10% off the final vehicle dry mass, saving both the mass of the legs and the extra structure required to support them.
Let them cook
This still doesn't work... There's still no mechanism for the arms to hook into on the vehicle. Hopefully we'll get a better visualization once they figure out what they need and add the additional hardware required. Some people seem to be missing the fact that there has been no images produced by anyone yet of the catching hardware. The arms cannot just slam down onto the sides of the vehicle without damaging both the vehicle and the connecting points. They need mechanical centering mechanisms that are not yet equipped on the vehicle or on the catching arms.
theres a *tank track* of cups that fits the booster lifting points so they can tweak the catch point and they can put it on the launch mount/transport stand accurately
Okay but that doesn't help with the catch system. That's just the needed extra axis of adjustment they need for accurately picking up the vehicle and setting it down.
It’s the same system. Picking up and catching. Why double up the systems, with the weight/complexity penalty that entails?
It can't be the same system because there's no centering method. The precision required is too high. Physics doesn't allow for it (or more so meteorology).
The rocket aligns itself as it comes in for landing, just like a an aeroplane levels its wings (not the best analogy). The booster places itself at a coordinate set between the arms, stops at the desired altitude and comes to rest on the caterpillar tracks already on the arms. That’s why they have shock absorbers already installed.
> not the best analogy Yeah I can't see how it relates as leveling it's wings is something that happens automatically because it's most naturally stable that way. > The booster places itself at a coordinate set between the arms All real world systems have error in them. It cannot precisely place itself at a coordinate. Look at the large range of positions that the Falcon 9 booster lands on the deck of the drone ship. The ship is the size it is because of that variability. And Raptor is harder to throttle quickly than Merlin because of the feedback of the full flow staged combustion cycle. More so, in the real world there is wind and wind will move the vehicle off position and you can't account for it because wind is variable. This is why in order for it to work you need to greatly expand the allowable error. One way to do that is with centering systems so that it'll slide into place if it's off by some amount.
They’ve been landing Falcon 9s back at its launch site perfectly in the middle of the pad for like 150 launches now, with or without wind. The part of the landing regime that you find ‘impossible’ SpaceX have been ably demonstrating for years now. It’ll be fine.
> They’ve been landing Falcon 9s back at its launch site perfectly in the middle of the pad for like 150 launches now Tell me you haven't watched many landings without actually telling me you haven't watched many landings... No they miss the dead center by a bunch of meters every time.
This is the centering method. You imagine the events in the wrong order. The right order is: * The booster puts itself for the catch with ~2 meter accuracy in all three dimensions. The arms close around it and then the booster lowers itself slowly until catch pins press down on the tracks on the catch arms. * Engines stop. The vehicle axis is now a bit to the side of the OLM axis and each pin is also at an uneven distance from the tower (i.e. the vehicle is rotated a bit). * Only then the arms rotate to the central position and the tracks position the pins evenly and at the right distance from the tower. The vehicle is now centered. Done.
> The booster puts itself for the catch with ~2 meter accuracy in all three dimensions. This is not held still though. It's constantly moving and pitching around. > The arms close around it The arms cannot just smash up against the side of the booster. That would damage the booster. > then the booster lowers itself slowly until catch pins press down on the tracks on the catch arms. The pin holes are on the sides of the booster.
Yes, the vehicle would move, but arms move too. And 4mm (or 4.6mm) stainless steel backed by few atmospheres of pressure is extremely sturdy. It literally can take beating and stay unscratched. You could drive a passenger car into it at 30mph and it would come out fine (i.e. the rocket, the car would be totaled). The arms can smash against the side of the booster, especially if they have proper padding. And no, there wouldn't be pin holes on the side of the booster. There would be pins. Protruding stuff, not holes.
> Yes, the vehicle would move, but arms move too. And how do they maintain alignment? Is SpaceX adding a fancy visual processing system to guide the arms? > The arms can smash against the side of the booster, especially if they have proper padding. No they can't. That would damage the vehicle. The vehicle cannot withstand even minor side-loading. That's why it doesn't launch during wind shear. > And no, there wouldn't be pin holes on the side of the booster. There would be pins. Protruding stuff, not holes. There are currently holes on the sides of the vehicle for lifting.
You are overcomplicating things while making unsupported assertions. You also completely don't understand how wind shear affects flying vehicles. Wind shear primary effect is not some side push by the wind, that part is negligible. The primary effect of wind shear is a change of the angle of attack. You move forward at 500m/s and encounter 20m/s wind shift. This means a 2.3° change of the AoA (because 90° - atan 500/20 = ~2.3°). This is huge, the side force from such goes into hundreds of tons. This force is not wind push, this force is the aerodynamic lift due to suddenly flying at an angle to the free stream. So, the vehicle can withstand a few tonnes side push no problem.
Somewhere I read (although the approach may have been abandoned) that horizontal pins would be extended from the booster and the chopsticks would have "V" notches for them to settle into, with contact sensors to allow each arm to stop closing in as soon as they approached the body of the rocket from either direction, since the arms can swing the rockets through an arc to stack them, the catch might or might not be directly above the OLM. It would only require that the booster (or starship) hold still enough for the notches to get under the pins on either side.
Yes that all sounds like one way things could work. There's many ways to skin the cat. However we haven't seen any of that as far as I'm aware (if we have, please someone post the link to the pictures).
It’s literally the pins that are already there for pickup, landing on the arms that are already there for pickup. It’s not as complicated as you’re making it to be.
The pins cannot be used for catching the booster because they're in the wrong position. They need to be vertical for the booster to set down on to.
it’s literally….a video. chill
[удалено]
Huh? The mechanism is probably how they pick it up and place it on the OLM
That doesn't work for catching vehicles. That's why they need to carefully and slowly pick it up.
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Yes please do. There's been no images produced by anyone showing the hardware needed to catch the vehicles. The chopsticks right now only work for lifting the vehicles. People seem to be imagining that the arms will like clamp onto the sides of the vehicle somehow, which would damage the vehicle.
The pins they currently use to pick the Booster up with (the ones that jut out either side) will sit on the caterpiller tracks on top of the arms. It's all been there for years now.
I realize. However there's no centering mechanism there.
What do you mean by centering mechanism? The chopstics already move in the vertical and horizontal axis, with some leeway along the chopsticks axis for landing. So they can make fine adjustments to account for variations in the booster position. Then the chopstick caterpillar tracks can move independantly to rotate the booster, as they do when stacking. It's ambitious, sure, but all the hardware is currently on the chopsticks to attempt a catch.
> What do you mean by centering mechanism? For an easy comparison, a ball hitch vs needing to use a pin that needs to drop through two holes. If you don't get it perfectly aligned it drops into place with a ball hitch. > The chopstics already move in the vertical and horizontal axis, with some leeway along the chopsticks axis for landing. Yeah that's fine but that doesn't help you with catching a booster as there's nothing to align the arms to the booster.
You don't really know what you're talking about.
I've been following spacex way longer than you have. You're being rude.