|
Ronsmytheiii
|
|
« on: 03/17/2012 05:24 AM » |
|
This paper introduces a concept for a single-person spacecraft and presents plans for flying a low-cost, robotic demonstration mission. Called FlexCraft, the vehicle integrates propulsion and robotics into a small spacecraft that enables rapid, shirt-sleeve access to space. It can be flown by astronauts or tele-operated and is equipped with interchangeable manipulators used for maintaining the International Space Station (ISS), exploring asteroids, and servicing telescopes or satellites. Most FlexCraft systems are verified using ground facilities; however, a test in the weightless environment is needed to assess propulsion and manipulator performance. For this, a simplified, unmanned, version of FlexCraft is flown on a low-cost launch vehicle to a 350 km circular orbit. After separation from the upper stage, the vehicle returns to a target box mounted on the stage testing the propulsion and control capability. The box is equipped with manipulator test items that are representative of tasks performed on ISS, asteroid missions, or for satellites servicing. http://nasainvitation.com/files/FlexCraft_Griffin_%2006-03-11.pdf
|
|
|
|
Advertisement
|
|
« on: 03/17/2012 05:24 AM » |
|
|
|
|
|
|
|
JohnFornaro
|
|
« Reply #1 on: 03/17/2012 12:16 PM » |
|
I think this is a great presentation, and for in-space ops, the right way to go. Space suits should be for planetary ops. From the article: Space suits are a logical choice for planetary operations; however for safe, rapid access to the weightless environment, spacecraft offer compelling advantages.
|
|
|
|
IRobot
|
|
« Reply #2 on: 03/17/2012 06:19 PM » |
|
...then 10 years after this is done someone will conclude that an human EVA can be done remotely with high definition cameras...
Why don't they just go ahead for a 100% tele operated device? Does that "kill" the space enthusiasm?
|
|
|
|
QuantumG
|
|
« Reply #3 on: 03/17/2012 11:19 PM » |
|
Have you seen the comms that are available? First you have to solve that problem (and it wouldn't be a bad idea anyway).
|
|
|
|
spectre9
|
|
« Reply #4 on: 03/18/2012 04:18 AM » |
|
Great presentation really makes a good case for it. I'm sure it would be lots and fun and not having to work at the lower suit pressure will be a big bonus. Robotic manipulators will have to be good but it seems like these are getting better all the time. Can it replace the space suit? I wouldn't know about that.
|
|
|
|
Robotbeat
|
|
« Reply #5 on: 03/18/2012 05:54 AM » |
|
This is less flexible, less nimble, etc, than an actual EVA.
There are other ways to allow low- or no- prebreathe EVAs than this half-ton spacecraft with very low delta-v capability (less than the Shuttle's MMU). Spacesuits are more capable and less massive.
|
|
|
|
pathfinder_01
|
|
« Reply #6 on: 03/18/2012 06:13 AM » |
|
This is less flexible, less nimble, etc, than an actual EVA.
There are other ways to allow low- or no- prebreathe EVAs than this half-ton spacecraft with very low delta-v capability (less than the Shuttle's MMU). Spacesuits are more capable and less massive.
Depends. Hardshell spacesuits would allow fast EVA from standard ISS pressure but they are also heavy. Then there is the option of a pure Oxygen enviroment instead of Nitrogen/oxygen mix, but there are questions about long term health in one. Also I having a feeling a robot arm might be better than a glove in a lot of cases.
|
|
|
|
Robotbeat
|
|
« Reply #7 on: 03/18/2012 06:21 AM » |
|
This is less flexible, less nimble, etc, than an actual EVA.
There are other ways to allow low- or no- prebreathe EVAs than this half-ton spacecraft with very low delta-v capability (less than the Shuttle's MMU). Spacesuits are more capable and less massive.
Depends. Hardshell spacesuits would allow fast EVA from standard ISS pressure but they are also heavy.
Then there is the option of a pure Oxygen enviroment instead of Nitrogen/oxygen mix, but there are questions about long term health in one. ...
That's not the only possibility (and the hard suits are not half a ton, at least not the ones I've seen...). There's always operating at a slightly lower pressure, which reduces spacecraft mass (and reduces amount of nitrogen needed), and was considered by some recent proposals for a deep space hab, operating at about 73kPa. And the Orlan suit the Russians use only needs 30 minutes of pre-breathe.
|
|
|
|
Ronsmytheiii
|
|
« Reply #8 on: 03/18/2012 06:03 PM » |
|
This is less flexible, less nimble, etc, than an actual EVA.
There are other ways to allow low- or no- prebreathe EVAs than this half-ton spacecraft with very low delta-v capability (less than the Shuttle's MMU). Spacesuits are more capable and less massive.
Perhaps, but the ability to prestage items outside or do simple tasks remotely/ in Flexsuit could make EVA's in EMU's more productive and lessen their frequency and therefore crew risks. Also, the suit is probably aimed at NEA missions, so flexibility is probably not as great as needed for station EVA's.
|
|
|
|
RocketmanUS
|
|
« Reply #9 on: 03/18/2012 07:06 PM » |
|
I don't think it would replace the spacesuit for in space use.
Could be used to transfer one person to another station or space craft.
Not being in a tight space suit has it's advantages and comfort. For one the need of the restroom, less of a problem in the single person craft.
Also good for a short EVA, not all the wasted time needed for the prebreathe. For on a planet the spacesuit would most likely be the best ( same pressure as in the base or mobile craft.
|
|
|
|
simonbp
|
|
« Reply #10 on: 03/18/2012 08:16 PM » |
|
This is less flexible, less nimble, etc, than an actual EVA.
Citation?  Legs are more of a hindrance than help in microgravity, and the arms of a pressurized suit are anything but flexible. Indeed, given how bad EVA suit gloves damage their user's hands after just a day of use, it's hard to think of anything that would worse than an EVA suit. Suits are used today out of history (Apollo-heritage), not because they are the objectively best design (they are for a surface, not in microgravity). Something like FlexCraft sounds like a quantum leap in EVA usability and capabilities.
|
|
|
|
Robotbeat
|
|
« Reply #11 on: 03/19/2012 02:17 AM » |
|
We are still using practically Apollo-heritage suits. It's not like there aren't better suit concepts out there, we've just been stuck with the ones we have for a long time (since the start of Shuttle). There are better glove designs out there, too: http://en.wikipedia.org/wiki/Centennial_Challenges#Astronaut_glove_challengeHere's a suit that's both more mobile than current EVA suits and doesn't require pre-breathing: http://en.wikipedia.org/wiki/Mark_III_(space_suit) And there's always this sort of space suit:
http://www.youtube.com/v/KhB9uWZZPFo&rel=1and this one (I like it in that it is very minimal, relying on the human body for heat regulation, as an integral part of the pressure vessel, etc...) : http://en.wikipedia.org/wiki/Space_activity_suitHaving to rely entirely on the propulsion system for translating from one point to another seems a little risky to me. And using the mechanical limbs for moving from place to place sounds awkward and inefficient. Also, what kind of force feedback is really possible with something like that? I feel like if you are going for something like the FlexCraft, there's hardly an reason to have it manned at all. Might as well remotely pilot it all the time. And if you're going to do that, then there are other approaches that are much less massive (so you could bring two of them for the same mass as one FlexCraft, plus they could have more delta-v capability, could be used for longer lengths of time, etc).
|
|
|
|
Patchouli
|
|
« Reply #12 on: 03/19/2012 05:31 PM » |
|
This is less flexible, less nimble, etc, than an actual EVA.
Citation? 
Legs are more of a hindrance than help in microgravity, and the arms of a pressurized suit are anything but flexible. Indeed, given how bad EVA suit gloves damage their user's hands after just a day of use, it's hard to think of anything that would worse than an EVA suit.
Suits are used today out of history (Apollo-heritage), not because they are the objectively best design (they are for a surface, not in microgravity). Something like FlexCraft sounds like a quantum leap in EVA usability and capabilities.
I think it could be pretty useful the potential is enough to warrant building one and testing it. It's kinda like a space version of deep worker. Now the advantages it would be more comfortable for crew ,offer a better field of vision then cameras without worries of loss of signal offer, far better MMOD protection, and a slightly better radiation protection.
|
|
|
|
Robotbeat
|
|
« Reply #13 on: 03/19/2012 08:32 PM » |
|
Looks great to me! I like this idea. (Communications issues aside) you could put 4 or more of these on a F9.
And how many space suits?
|
|
|
|
IRobot
|
|
« Reply #14 on: 03/19/2012 09:33 PM » |
|
Looks great to me! I like this idea. (Communications issues aside) you could put 4 or more of these on a F9.
And how many space suits? 
One specific for each astronaut. Pretty bad actually.
|
|
|
|