Orb2 Space Station

[DreamyPickle]

Didn't find anything related to this on the forum so I thought I'd start a new thread.

Website: www.orb2.com
Paper: Orb2: Spherical Space Station Designed for Single Launch and
On-Orbit Assembly
Video:

The proposed Orb2 design consists of a spherical habitation module
and a cylindrical service module. The habitation module avoids the volume limitation by being
launched in a flat-packed stack and assembled and welded robotically in orbit. Using CAD and
finite element analysis, this paper shows that the habitation module contains approximately
2000 m3 of pressurized volume, with a mass of 24 tons, and can hold four times the standard
atmospheric pressure. Moreover, the Whipple shield configuration is identical to the heavily
protected sections of the International Space Station. The service module has a much smaller,
traditional cylindrical design and its role is to provide all the life support, necessary utilities,
and docking ports

Current design seems to be based on New Glenn, probably because it's the widest fairing available. The SpaceX starship is also mention as a future option.

It's not clear if they have any investors but there are not many other projects serious about welding pressure vessels directly on orbit.

[baldusi]

Totally not practical for the current market. But really interesting idea. I think a welding head and some samples to make a small scale demonstrator on the ISS would be totally worth it.

[webdan]

Agreed, interesting concept.

The music seems like a total ripoff of Oxygène by Jean Michel Jarre...

[Asteroza]

Seems like an interesting side experiment for a SpiderFab/Archinaut demo, provided you had a lot of arms (the paper seems to think you can get away with just one arm though, via aux clamps/bolts/tack welds and grapple points on the surfaces, though supplying power becomes problematic). For a SpiderFab/Archinaut you probably need at least 2 arms per piece to be joined or maybe 3 since you are inducing a potentially 3D bend, plus the weld head arm, so you are looking at at least 5 arms, maybe 7, plus however many arms you need to steady yourself against a building base, so all in 8 arms maybe? Oh hey, 8 arms, spider...

But a lot of the conceptual fabber concepts usually have less than 8 arms though...

[Zed_Noir]

There is a thread on Orb2 from the person who did the Youtube video in the Advanced Concepts section.

https://forum.nasaspaceflight.com/index.php?topic=50595.0

[TrevorMonty]

The design concept looks good. Latching them together then welding afterwould means they only need one arm, as per video. I would've thought friction stir welding would be better.

[TrevorMonty]

Sphere is 15m in diameter.

[novak]

Latching them together then welding afterwould means they only need one arm, as per video. I would've thought friction stir welding would be better.

Structurally, probably, if it's aluminum.  But friction stir welding is also going to require something going through the piece to be welded and clamping against the surface, and then you have to remove the welder and plug the hole. 

I don't think this concept is that well fleshed out though, so this may be a premature attempt at optimization.

[edzieba]

That's going to be a real buttock-clencher of a pressurisation. No way to test it hydraulically, so at best they can go for a low-pressure leak test (pressurise to some low value and watch for a few weeks to see if that pressure drops, accounting for variance from heating) and then go to full pressure. 1ATM for a 15m diameter sphere gives about 71.6MN wanting to throw those hex/pent segments around if any of the welds are not up to scratch. The leak test finds any leaks, but does not tell you much about actual joint strength. Non-destructive testing (i.e. stick an X-ray head on that arm) helps, but it's not going to be a fun time filling that sphere up!