7 ms·

Station Crew Docks Dragon Capsule to ISS

227 points by mzaccari 12y ago

mariocesar 12y ago
Tomorrow is happening today
aidos 12y ago
Whenever I see ISS dockings I wonder why the arm isn't computer controlled. There's no specific information on this page but I'm assuming it was a manual docking. Can anyone explain why the process is still manual?
- FranOntanaya 12y ago
  I bet the trainers that certify an astronaut is precise enough to get it done are a lot cheaper than the engineers required to certify a computer wouldn't karate chop the station.
  - tomswartz07 12y ago
    I think that the arm was designed specifically to be manually controlled. Even though it might be possible to 'computerize' the control, realistically there's no benefit to doing so.
  - icegreentea 12y ago
    The arm almost certainly has a control system that can resolve that. Since humans suck at higher order control, the arm almost certainly has a control system that takes the operator's desired output (which will be a series of joint angles), and converts into the required motor torques. In this process, the control system almost certainly also does sanity checks to prevent self-intersections, collision with the space station, overtorqeuing the motors, and etc. Replacing the human with a computer program therefore likely doesn't literally involve verifying that it will not karate chop the station - lower level control will take care of that for you. However, as anyone who has worked with robot manipulators before, actually getting good performance out of them in variable environments (ie, not a controlled factory assembly line) is quite a bit of work - work that probably isn't worth it.
  - Shivetya 12y ago
    considering the first flight where they were rewriting code while it sat outside the station; reconfigured the LIDAR on the fly; I would put it down being overly cautious, maybe a bit of fear? Let us be honest, with all the difficulty of getting that module into space docking isn't that big of a deal. If there were no people on board no one would care. Plus I have to ask, if a thruster suddenly misfires or goes haywire who is going to be faster? In Apollo days I would put odds on the astronauts, today - I am betting on a computer. We will sooner trust a car to drive itself before we allow a freighter to dock with a space station.
- drzaiusapelord 12y ago
  The cynical part of me thinks because manned spaceflight, at least in the context of being stuck in a LEO tin can, is of questionable utility and we try to find things for people to do? We can automate quite a bit of this, in fact, the ESA's Automated Transfer Vehicle just docks itself. Wikipedia: At a distance of 249 m, the ATV computers use videometer and telegoniometer data for final approach and docking manoeuvres. The actual docking to Zvezda is fully automatic. If there are any last-minute problems, a pre-programmed sequence of anti-collision manoeuvres, fully independent of the main navigation system, can be activated by the flight engineers aboard the station. http://en.wikipedia.org/wiki/Automated_Transfer_Vehicle http://en.wikipedia.org/wiki/Automated_Transfer_Vehicle Or what's that apocryphal story about early astronauts fighting with NASA engineers to put in pilot controls with manual override so these guys could claim to be pilots and not mere passengers? The ugly truth is a lot of this stuff is best left to automation, robots, etc.
  - idlewords 12y ago
    In the Shuttle, the landing gear control was intentionally left outside computer control so that the vehicle could not be flown unmanned. Flight control software could autoland the shuttle from orbit, but it took a human being to let the wheels down. So I don't think your cynicism is excessive.
    - TeMPOraL 12y ago
      Meanwhile Russians could successfully auto-land a shuttle in high wind. http://en.wikipedia.org/wiki/Buran_%28spacecraft%29#Flight_into_space http://en.wikipedia.org/wiki/Buran_%28spacecraft%29#Flight_i... Buran was an amazing piece of technology. It's sad it didn't get its chance.
      - vermontdevil 12y ago
        The US Air Force has one up there now - X-37B. It's completely autonomous. http://en.wikipedia.org/wiki/Boeing_X-37 http://en.wikipedia.org/wiki/Boeing_X-37
- VLM 12y ago
  Best described as a scaling problem with manual or prototype, vs automated. Lets say you need a prototype ability tool and die maker machinist on staff to handle "things" during development. And you need a simple piece of threaded rod. You could blow a lot of extra time and money on getting a CNC programmer and the software and a numerically controlled lathe or machining center dropped in to make that boring simple little piece of threaded rod. Or you could say, "dude, I know this is beneath your skill, but you're just sitting there burning oxygen and it'll only take ten minutes for you to machine a piece of threaded rod, so ..." If you have a tool that's designed to do anything, and the tool and op are just sitting there, even if you could automate a one-off, the overall system cost and productivity is higher if the op just does it by hand. If you have a VERY active schedule, and maybe 3 simultaneously operating 24x7 arms all over the station with only one dude available to run all the arms and everything at 150% of designed thruput capacity etc, then it would make economic sense to automate this task so the arm op can work on something more human oriented, but ...
- kordless 12y ago
  Here's more info on the arm: http://www.nasa.gov/mission_pages/station/structure/elements/mss.html http://www.nasa.gov/mission_pages/station/structure/elements...
- adamfeldman 12y ago
  In fact the arm can be remotely controlled. As of 2005[1] ground controllers can uplink sequences of commands for the arm to complete. According to an article[2] about this Dragon launch, DEXTRE (two-armed human-like remote manipulator) will be remotely commanded to unpack cargo from the Dragon's unpressurized trunk and mount it on the station. I believe this is not a new thing at all. [1]: http://www.space.com/1033-remote-access-canadarm-2-hand-ground-control.html http://www.space.com/1033-remote-access-canadarm-2-hand-grou... [2]: http://spaceflightnow.com/falcon9/013/140923arrival/#.VCHgLy5dWhY http://spaceflightnow.com/falcon9/013/140923arrival/#.VCHgLy...
bvm 12y ago
It's technically a berthing, not a docking as it mates under the power of the Candarm, not under its own steam.
- xyclos 12y ago
  correct, and the body of the article correctly identifies it as such.
- mzaccari 12y ago
  Thank you for the clarification. I corrected the title
- idlewords 12y ago
  MATES UNDER THE POWER OF THE CANADARM
  - Intermernet 12y ago
    Out of context, this sounds like a line from a very bad book. Have an upvote.
    - possibilistic 12y ago
      To both parent and GP: Please don't comment on HN like you would on Reddit. If you don't have questions or information to add to the thread, you should probably use that as a cue to refrain from posting. Joke posts might not seem bad, but in aggregate they lower the signal to noise ratio we have come to appreciate about HN. Additionally, once these kinds of jocular posts start, it becomes infectious. I'm not trying to be mean; I'm guilty of making posts like this too. Many of us simply do not want to see HN devolve into the equivalent of a spammy subreddit. It's important that we all remind each other of the value of this community so that we can protect it from spiraling into a bad state.
      - idlewords 12y ago
        Please don't tell others how to post. It's patronizing. There's a voting system you can use to express your concern.
readerrrr 12y ago
And that is their second launch within 14 days. The previous launch was a satellite to a geostationary orbit.
- bfe 12y ago
  This 14-day interval between Falcon 9 launches was the fastest consecutive launch since Gemini 7 & 6A in December 4 & 15, 1965. SpaceX plans to beat that record soon with launches a week apart becoming routine.
  - ewoodrich 12y ago
    Gemini 7 and 6A were manned launches on human-rated launch vehicles, so it isn't quite comparable yet.
    - bfe 12y ago
      Still, modern launch vehicle human ratings were only developed after the second Shuttle disaster, and are far beyond 1965 standards. http://nodis3.gsfc.nasa.gov/displayDir.cfm?Internal_ID=N_PR_8705_002B_ http://nodis3.gsfc.nasa.gov/displayDir.cfm?Internal_ID=N_PR_... Falcon 9 v1.1 is almost certainly safer than the Titan II Gemini Launch Vehicle. As with prior Dragon flights, humans could have flown and been just fine.
    - jessaustin 12y ago
      It's comparable to any consecutive launches that occurred in the nearly five decades since.
  - ChuckMcM 12y ago
    And that is what I find fascinating. Weekly launches into even low earth orbit is a tremendous capability to lob stuff up there. I do look forward to the Dragon2 tests, and the next F9R landing attempt.
  - syncsynchalt 12y ago
    Unfortunately they've only got two F9 orbital launches planned for the entire rest of the year.
markab21 12y ago
Does anyone know what happens to the pod after a shuttle-craft docks and delivers cargo? Do they push it back to earth? Into space, leave it in orbit?
- andyjohnson0 12y ago
  It will stay at the ISS for a month to allow cargo transfer [1]. Then it returns to earth under its own power and is re-used after refurbishment [2]. [1] http://www.nasa.gov/content/expedition-41-trio-waits-for-dragon-and-new-soyuz/index.html#.VCF3zvldV2s http://www.nasa.gov/content/expedition-41-trio-waits-for-dra... [2] http://www.spaceflight101.com/dragon-spacecraft-information.html http://www.spaceflight101.com/dragon-spacecraft-information....
  - Zuph 12y ago
    Although the Dragon is reusable, SpaceX's contract with NASA stipulates that new capsules be used for each resupply mission. Not sure if the contract allows SpaceX to refurbish the capsules for other commercial missions, but the other CRS Dragons are being used for showpieces at the moment.
    - andyjohnson0 12y ago
      Interesting - I didn't know that. Do you know if this is due to NASA being general cautions with a new, relatively unproved vehicle? Or is it a condition of human-rating the Dragon?
      - arjunnarayan 12y ago
        General caution.
      - rst 12y ago
        NASA was unwilling to believe any discount offered for use of a refurbished spacecraft until they'd actually done it, so the bid was made on the basis of a new capsule for each mission. (The human-rated Dragon is going to be a different version anyway, with altered docking support, much beefier propulsion, altered solar panels, and of course, internal controls and life support. Current plan is new spacecraft permission there, too, though, perhaps for the same reason.)
MrBra 12y ago
Is it common to use metric system when launching rockets to space or is it a peculiarity of SpaceX? I heard the speaker on SpaceX channel always referring to kilometers and kilometers per second when talking about height and speed.
- jimktrains2 12y ago
  It's common in science in general to use Metric and not Customary. NASA is a/the notable hold out. Engineering is sometimes done in customary because of contracts and such, especially when dealing with government agencies. While I love Customary volumes (powers of 2 base units), the rest could stand a change and am glad SpaceX is using Metric.
- antimagic 12y ago
  It's common for pretty much all of engineering really. It's ludicrous to make calculations a bit more complicated by using weird non-SI units. The fact that NASA managed to crash a probe into Mars because they hadn't yet learned the lesson says it all really. Just use SI units and stop worrying about it.
  - thenmar 12y ago
    If anyone is curious, it looks like it was the fault of Lockheed. NASA's contract specified SI units: http://en.wikipedia.org/wiki/Mars_Climate_Orbiter http://en.wikipedia.org/wiki/Mars_Climate_Orbiter
  - Ankaios 12y ago
    No, the important lesson is to always label your units, and another one might be to always be careful passing dimensionful numbers between codes and teams. You can run into the same problem by accidentally even forgetting to convert between, e.g., newtons and millinewtons.
    - lotsofmangos 12y ago
      Even if you label your units, you get conversion errors that can easily multiply up into something nasty that goes boom.
ANH 12y ago
Of note, there is an Earth observation instrument, RapidScat, being carried in the Dragon's trunk, which will be (has been?) plucked off the capsule by operators on the ground. This one measures wind. Another, called CATS, will be similarly deployed on the outside of the ISS in December-ish; it will measure clouds and aerosols. These are part of a collection of low-cost (well, lower than a full satellite) Earth observation instruments to take advantage of the external mount points on the ISS. NASA recently had a media briefing about this: http://www.nasa.gov/press/2014/september/nasa-hosts-media-briefing-to-announce-new-earth-observing-role-for/ http://www.nasa.gov/press/2014/september/nasa-hosts-media-br...
s369610 12y ago
"support 255 research investigations", I hope that 255 is just a coincidence and that research isn't limited by 8 bits

227 points by mzaccari 12y ago

Tomorrow is happening today

aidos 12y ago

Whenever I see ISS dockings I wonder why the arm isn't computer controlled. There's no specific information on this page but I'm assuming it was a manual docking. Can anyone explain why the process is still manual?

FranOntanaya 12y ago
I bet the trainers that certify an astronaut is precise enough to get it done are a lot cheaper than the engineers required to certify a computer wouldn't karate chop the station.
- tomswartz07 12y ago
  I think that the arm was designed specifically to be manually controlled. Even though it might be possible to 'computerize' the control, realistically there's no benefit to doing so.
- icegreentea 12y ago
  The arm almost certainly has a control system that can resolve that. Since humans suck at higher order control, the arm almost certainly has a control system that takes the operator's desired output (which will be a series of joint angles), and converts into the required motor torques. In this process, the control system almost certainly also does sanity checks to prevent self-intersections, collision with the space station, overtorqeuing the motors, and etc. Replacing the human with a computer program therefore likely doesn't literally involve verifying that it will not karate chop the station - lower level control will take care of that for you. However, as anyone who has worked with robot manipulators before, actually getting good performance out of them in variable environments (ie, not a controlled factory assembly line) is quite a bit of work - work that probably isn't worth it.
- Shivetya 12y ago
  considering the first flight where they were rewriting code while it sat outside the station; reconfigured the LIDAR on the fly; I would put it down being overly cautious, maybe a bit of fear? Let us be honest, with all the difficulty of getting that module into space docking isn't that big of a deal. If there were no people on board no one would care. Plus I have to ask, if a thruster suddenly misfires or goes haywire who is going to be faster? In Apollo days I would put odds on the astronauts, today - I am betting on a computer. We will sooner trust a car to drive itself before we allow a freighter to dock with a space station.
drzaiusapelord 12y ago
The cynical part of me thinks because manned spaceflight, at least in the context of being stuck in a LEO tin can, is of questionable utility and we try to find things for people to do? We can automate quite a bit of this, in fact, the ESA's Automated Transfer Vehicle just docks itself. Wikipedia: At a distance of 249 m, the ATV computers use videometer and telegoniometer data for final approach and docking manoeuvres. The actual docking to Zvezda is fully automatic. If there are any last-minute problems, a pre-programmed sequence of anti-collision manoeuvres, fully independent of the main navigation system, can be activated by the flight engineers aboard the station. http://en.wikipedia.org/wiki/Automated_Transfer_Vehicle http://en.wikipedia.org/wiki/Automated_Transfer_Vehicle Or what's that apocryphal story about early astronauts fighting with NASA engineers to put in pilot controls with manual override so these guys could claim to be pilots and not mere passengers? The ugly truth is a lot of this stuff is best left to automation, robots, etc.
- idlewords 12y ago
  In the Shuttle, the landing gear control was intentionally left outside computer control so that the vehicle could not be flown unmanned. Flight control software could autoland the shuttle from orbit, but it took a human being to let the wheels down. So I don't think your cynicism is excessive.
  - TeMPOraL 12y ago
    Meanwhile Russians could successfully auto-land a shuttle in high wind. http://en.wikipedia.org/wiki/Buran_%28spacecraft%29#Flight_into_space http://en.wikipedia.org/wiki/Buran_%28spacecraft%29#Flight_i... Buran was an amazing piece of technology. It's sad it didn't get its chance.
    - vermontdevil 12y ago
      The US Air Force has one up there now - X-37B. It's completely autonomous. http://en.wikipedia.org/wiki/Boeing_X-37 http://en.wikipedia.org/wiki/Boeing_X-37
VLM 12y ago
Best described as a scaling problem with manual or prototype, vs automated. Lets say you need a prototype ability tool and die maker machinist on staff to handle "things" during development. And you need a simple piece of threaded rod. You could blow a lot of extra time and money on getting a CNC programmer and the software and a numerically controlled lathe or machining center dropped in to make that boring simple little piece of threaded rod. Or you could say, "dude, I know this is beneath your skill, but you're just sitting there burning oxygen and it'll only take ten minutes for you to machine a piece of threaded rod, so ..." If you have a tool that's designed to do anything, and the tool and op are just sitting there, even if you could automate a one-off, the overall system cost and productivity is higher if the op just does it by hand. If you have a VERY active schedule, and maybe 3 simultaneously operating 24x7 arms all over the station with only one dude available to run all the arms and everything at 150% of designed thruput capacity etc, then it would make economic sense to automate this task so the arm op can work on something more human oriented, but ...
kordless 12y ago
Here's more info on the arm: http://www.nasa.gov/mission_pages/station/structure/elements/mss.html http://www.nasa.gov/mission_pages/station/structure/elements...
adamfeldman 12y ago
In fact the arm can be remotely controlled. As of 2005[1] ground controllers can uplink sequences of commands for the arm to complete. According to an article[2] about this Dragon launch, DEXTRE (two-armed human-like remote manipulator) will be remotely commanded to unpack cargo from the Dragon's unpressurized trunk and mount it on the station. I believe this is not a new thing at all. [1]: http://www.space.com/1033-remote-access-canadarm-2-hand-ground-control.html http://www.space.com/1033-remote-access-canadarm-2-hand-grou... [2]: http://spaceflightnow.com/falcon9/013/140923arrival/#.VCHgLy5dWhY http://spaceflightnow.com/falcon9/013/140923arrival/#.VCHgLy...

bvm 12y ago

It's technically a berthing, not a docking as it mates under the power of the Candarm, not under its own steam.

xyclos 12y ago
correct, and the body of the article correctly identifies it as such.
mzaccari 12y ago
Thank you for the clarification. I corrected the title
idlewords 12y ago
MATES UNDER THE POWER OF THE CANADARM
- Intermernet 12y ago
  Out of context, this sounds like a line from a very bad book. Have an upvote.
  - possibilistic 12y ago
    To both parent and GP: Please don't comment on HN like you would on Reddit. If you don't have questions or information to add to the thread, you should probably use that as a cue to refrain from posting. Joke posts might not seem bad, but in aggregate they lower the signal to noise ratio we have come to appreciate about HN. Additionally, once these kinds of jocular posts start, it becomes infectious. I'm not trying to be mean; I'm guilty of making posts like this too. Many of us simply do not want to see HN devolve into the equivalent of a spammy subreddit. It's important that we all remind each other of the value of this community so that we can protect it from spiraling into a bad state.
    - idlewords 12y ago
      Please don't tell others how to post. It's patronizing. There's a voting system you can use to express your concern.

readerrrr 12y ago

And that is their second launch within 14 days. The previous launch was a satellite to a geostationary orbit.

bfe 12y ago
This 14-day interval between Falcon 9 launches was the fastest consecutive launch since Gemini 7 & 6A in December 4 & 15, 1965. SpaceX plans to beat that record soon with launches a week apart becoming routine.
- ewoodrich 12y ago
  Gemini 7 and 6A were manned launches on human-rated launch vehicles, so it isn't quite comparable yet.
  - bfe 12y ago
    Still, modern launch vehicle human ratings were only developed after the second Shuttle disaster, and are far beyond 1965 standards. http://nodis3.gsfc.nasa.gov/displayDir.cfm?Internal_ID=N_PR_8705_002B_ http://nodis3.gsfc.nasa.gov/displayDir.cfm?Internal_ID=N_PR_... Falcon 9 v1.1 is almost certainly safer than the Titan II Gemini Launch Vehicle. As with prior Dragon flights, humans could have flown and been just fine.
  - jessaustin 12y ago
    It's comparable to any consecutive launches that occurred in the nearly five decades since.
- ChuckMcM 12y ago
  And that is what I find fascinating. Weekly launches into even low earth orbit is a tremendous capability to lob stuff up there. I do look forward to the Dragon2 tests, and the next F9R landing attempt.
- syncsynchalt 12y ago
  Unfortunately they've only got two F9 orbital launches planned for the entire rest of the year.

markab21 12y ago

Does anyone know what happens to the pod after a shuttle-craft docks and delivers cargo? Do they push it back to earth? Into space, leave it in orbit?

andyjohnson0 12y ago
It will stay at the ISS for a month to allow cargo transfer [1]. Then it returns to earth under its own power and is re-used after refurbishment [2]. [1] http://www.nasa.gov/content/expedition-41-trio-waits-for-dragon-and-new-soyuz/index.html#.VCF3zvldV2s http://www.nasa.gov/content/expedition-41-trio-waits-for-dra... [2] http://www.spaceflight101.com/dragon-spacecraft-information.html http://www.spaceflight101.com/dragon-spacecraft-information....
- Zuph 12y ago
  Although the Dragon is reusable, SpaceX's contract with NASA stipulates that new capsules be used for each resupply mission. Not sure if the contract allows SpaceX to refurbish the capsules for other commercial missions, but the other CRS Dragons are being used for showpieces at the moment.
  - andyjohnson0 12y ago
    Interesting - I didn't know that. Do you know if this is due to NASA being general cautions with a new, relatively unproved vehicle? Or is it a condition of human-rating the Dragon?
    - arjunnarayan 12y ago
      General caution.
    - rst 12y ago
      NASA was unwilling to believe any discount offered for use of a refurbished spacecraft until they'd actually done it, so the bid was made on the basis of a new capsule for each mission. (The human-rated Dragon is going to be a different version anyway, with altered docking support, much beefier propulsion, altered solar panels, and of course, internal controls and life support. Current plan is new spacecraft permission there, too, though, perhaps for the same reason.)

MrBra 12y ago

Is it common to use metric system when launching rockets to space or is it a peculiarity of SpaceX? I heard the speaker on SpaceX channel always referring to kilometers and kilometers per second when talking about height and speed.

jimktrains2 12y ago
It's common in science in general to use Metric and not Customary. NASA is a/the notable hold out. Engineering is sometimes done in customary because of contracts and such, especially when dealing with government agencies. While I love Customary volumes (powers of 2 base units), the rest could stand a change and am glad SpaceX is using Metric.
antimagic 12y ago
It's common for pretty much all of engineering really. It's ludicrous to make calculations a bit more complicated by using weird non-SI units. The fact that NASA managed to crash a probe into Mars because they hadn't yet learned the lesson says it all really. Just use SI units and stop worrying about it.
- thenmar 12y ago
  If anyone is curious, it looks like it was the fault of Lockheed. NASA's contract specified SI units: http://en.wikipedia.org/wiki/Mars_Climate_Orbiter http://en.wikipedia.org/wiki/Mars_Climate_Orbiter
- Ankaios 12y ago
  No, the important lesson is to always label your units, and another one might be to always be careful passing dimensionful numbers between codes and teams. You can run into the same problem by accidentally even forgetting to convert between, e.g., newtons and millinewtons.
  - lotsofmangos 12y ago
    Even if you label your units, you get conversion errors that can easily multiply up into something nasty that goes boom.

ANH 12y ago

Of note, there is an Earth observation instrument, RapidScat, being carried in the Dragon's trunk, which will be (has been?) plucked off the capsule by operators on the ground. This one measures wind. Another, called CATS, will be similarly deployed on the outside of the ISS in December-ish; it will measure clouds and aerosols. These are part of a collection of low-cost (well, lower than a full satellite) Earth observation instruments to take advantage of the external mount points on the ISS. NASA recently had a media briefing about this: http://www.nasa.gov/press/2014/september/nasa-hosts-media-briefing-to-announce-new-earth-observing-role-for/ http://www.nasa.gov/press/2014/september/nasa-hosts-media-br...

s369610 12y ago

"support 255 research investigations", I hope that 255 is just a coincidence and that research isn't limited by 8 bits