Vast, a startup for quote: human habitation, first in LEO, and then beyond

[Twark_Main]

I just mentioned in another thread that it's important to be working on the right "long pole" problem. But I haven't yet said what I think that is.

For Vast, I believe their long pole is cheap (possibly autonomous) reconfiguration of a modular space station. This lets them scale to arbitrary size without the costly conventional ISS approach.

How?

   • Each module is its own independently-maneuverable autonomous spaceship.

That will make the overall design far more expensive, and that hardware becomes dead mass once all the modules are assembled. It would cost far less to just use a space tug to move the modules.

Tell that to Axiom.

The "dead mass" idea assumes that the modules never disconnect, even in contingency and redundancy reconfiguration scenarios. It also assumes that spare parts are never repurposed.

   • Each module is relatively cheap (serial batch production with extensive commonality between modules).

As one of the few people with manufacturing experience on NSF, I just want to point out that serial production does not automatically mean "cheap". It is the design that dictates cost, such as whether you add engines to every module or not (related to my comment above) instead of using a space tug to move the modules once they are in space.

Having a standardized design is another factor, regardless if the modules are made individually, in batches, or in serial production.

Yep. Standardized design, serial production.

Nothing automatically works, naturally. But at least "success is one of the possible outcomes."

   • Critical inter-module connections automatically connect when joined (non-critical interfaces can still be done by hand). This means very early construction has the option to be 100% unmanned.

The first manufacturing company I worked for made electrical connectors. The big cylindrical ones you see on military equipment, and in space. There are varieties of those that can do blind connections (i.e. just push together the equipment), but insisting every connection be made this way

That's exactly what I'm not insisting. That's why I pointed out that many connections will still be done by hand.

It sounds like you are in "violent agreement" with me.

   • An incremental scaling approach that generates revenue along the way.

Which is something that everyone is always hoping to have, but it is tough to get. This is such an immature market that it is tough to understand which portion of the market to focus on first.

Science, obviously. With a side order of space tourism.

   • Each module is its own independently-maneuverable autonomous spaceship.

I can't see anything on their website that even hints this.

As I wrote,

Looks like the 100 meter long dumbbell station is made from 11 separate modules, each one its own independent spacecraft (see double-line gaps, RCS "dots" ala Axiom). The modules are all ~6 m diameter and ~8 m long, except the core (spin axis) module and one end, which are both ~13 meters long.

Want to build a big torus? Sure! All you do is gang together curving modules instead of parallel ones.

You also need modules with extra ports to serve as junctions (to allow modules to be used as spokes, at right-angles to the torus)

Correct. I suspect the central axis module (showing a large "hatch" or "door") is the early prototype.

[Twark_Main]

, and a completely different type of module or modules to be used for the hub. And the forces on a docking/attachment system that hangs "vertically" in a baton is very different from the torque on modules that hang "horizontally" from each other.

(A wheel is a more complex beast than a stick. Who knew.)

The neat part about wheels is, you don't actually need a hub. The tensile strength of the modules is plenty strong enough on its own. Remember, longitudinal tension is half of hoop tension in cylindrical pressure vessels.

Most people picture torus stations like a bridge, "hanging" from the central hub. Instead, imagine the docking tunnel & port as a pressure-supported guyed tensegrity tower, "sticking up" from the (self-supporting) toroidal ring section.

This uses less mass, which is of course the main reason. It also completely avoids the problem of weird differential expansion between the wheel segments and the spoke segments (due to rotation/pressurization/thermal).

This also has the decided advantage that it can be engineered to break off harmlessly if you crash a ship into it.


I see a ton of "traditional" wheels ala the movie 2001. I see none of that design, though? It seems to be a weird blind spot in the Structures Department.

[Twark_Main]

I see a ton of "traditional" wheels ala the movie 2001. I see none of that design, though? It seems to be a weird blind spot in the Structures Department.

I figured it out. Akin's Laws strike again!

30. (von Tiesenhausen's Law of Engineering Design) If you want to have a maximum effect on the design of a new engineering system, learn to draw. Engineers always wind up designing the vehicle to look like the initial artist's concept.

shakes fist at sky

[Asteroza]

I see a ton of "traditional" wheels ala the movie 2001. I see none of that design, though? It seems to be a weird blind spot in the Structures Department.

I figured it out. Akin's Laws strike again!

30. (von Tiesenhausen's Law of Engineering Design) If you want to have a maximum effect on the design of a new engineering system, learn to draw. Engineers always wind up designing the vehicle to look like the initial artist's concept.

shakes fist at sky

It's less a blind spot, and more a practical issue. A rotating station that is "hubless" will still need a means to dock and transfer from a non-rotating vehicle to the station and back, if it doesn't spinup/down for every docking.

Well, unless you expect a visiting vehicle to hand off cargo pods with active robot arms between station and vehicle

Err, maybe not, but in my mind the alternative REQUIRES a large circular structure, and a lot of mass compensation. Basic variant is a podcar on a circular track on the outside of the ring, slowing down like a spindown hub device but "stopping" while riding the ring edge. Stuff can dock to that. The much larger variation is the circular deck/infinite runway concept, where a visiting vehicle interfaces with the deck (think maglev pads or even wheels) while lightly thrusting down for contact and "dragged" to spin gravity, almost like a spaceplane touching down on a landing strip. Either way, the vehicle to station mass ratio must go to stupid to pull that off, since shifting mass to compensate for CG shifts would be a major pain. Having the visiting vehicle spun up at hub center to station rotation speed, then if necessary shift "down", makes for a much cleaner mass shift to compensate for.

[Paul451]

It's less a blind spot, and more a practical issue. A rotating station that is "hubless"

He doesn't mean truly hubless, just that the hub isn't structural. The docking system is on "top" of a mast-like tower extending from the torus.

So the dock (and zero-g lab) is still at the centre of rotation, but with a single arm down to the torus.


I've seen concept art of toroidal stations with this design, but google-fu is too weak to bring up an example on demand.

[Paul451]

Meh. Just drew it. It's not like the concept needs concept art.

(If you don't want a zero-g lab, you can also just skip the hub entirely, but keep the arm. The visiting ships have docking ports on their sides and go inside the wheel to dock with the arm, reducing the effect of asymmetrical mass on the station even further. Even through wheel stations are virtually immune, Starship's a big beast.)

[Twark_Main]

It's not like the concept needs concept art.

That's what I always say, but then people misread my words and blame me because I didn't draw a picture.

you can also just skip the hub entirely, but keep the arm. The visiting ships have docking ports on their sides and go inside the wheel to dock with the arm, reducing the effect of asymmetrical mass

The ballast necessary for that will be... not small.

The problem is more the rapid shift in ballast. You're going to get some very off-nominal forces, requiring additional mass and strength over the entire station.

If the structure was a perfectly rigid body then there'a no problem, of course. Space stations are very far from perfectly rigid, however.

AFAICT such true "hubless" designs are strictly worse than "tower" designs, which are themselves strictly superior to the commonplace "wheel."

[Paul451]

It's not like the concept needs concept art.

That's what I always say, but then people misread my words and blame me because I didn't draw a picture.

I did draw a picture. I didn't draw art

you can also just skip the hub entirely, but keep the arm. The visiting ships have docking ports on their sides and go inside the wheel to dock with the arm, reducing the effect of asymmetrical mass

The ballast necessary for that will be... not small.
The problem is more the rapid shift in ballast. You're going to get some very off-nominal forces, requiring additional mass and strength over the entire station.

"But keep the arm." Ie, the ship docks at the centre of the station. Sans hub, it becomes the hub. The docking port is at the top of the arm/tower.

[Twark_Main]

I didn't draw art

Now that, good sir, is a matter of opinion! 

"But keep the arm." Ie, the ship docks at the centre of the station. Sans hub, it becomes the hub. The docking port is at the top of the arm/tower.

Roger, understood now.

To avoid weird moments you'd want the center-of-mass of the ship to have a certain stand-off distance from the docking plane. This isn't that hard to achieve when planning the cargo layout. Worst-case it might impose some limitations on vehicle choice.

One option is a docking tower that gets longer and shorter to compensate, but at that point we're probably squandering our simplicity gains.

Intriguing concept! Thanks.


EDIT: I have disentangled all the Vast-related stuff into separate posts, and kindly requested that the moderators move all the posts starting from this post up to and including the current post right here, over to the Rotating Space Stations thread. Mea culpa!

Let's take any non-Vast related discussion posts over there. Thanks everyone.

[meekGee]

, and a completely different type of module or modules to be used for the hub. And the forces on a docking/attachment system that hangs "vertically" in a baton is very different from the torque on modules that hang "horizontally" from each other.

(A wheel is a more complex beast than a stick. Who knew.)

The neat part about wheels is, you don't actually need a hub. The tensile strength of the modules is plenty strong enough on its own. Remember, longitudinal tension is half of hoop tension in cylindrical pressure vessels.

Most people picture torus stations like a bridge, "hanging" from the central hub. Instead, imagine the docking tunnel & port as a pressure-supported guyed tensegrity tower, "sticking up" from the (self-supporting) toroidal ring section.

This uses less mass, which is of course the main reason. It also completely avoids the problem of weird differential expansion between the wheel segments and the spoke segments (due to rotation/pressurization/thermal).

This also has the decided advantage that it can be engineered to break off harmlessly if you crash a ship into it.


I see a ton of "traditional" wheels ala the movie 2001. I see none of that design, though? It seems to be a weird blind spot in the Structures Department.

My problem with a hubless wheel is that while it may be in static equilibrium, it has a very soft primary oscillatory mode - going from round to oval to round to perpendicular-oval...

The only way to kill that mode is with spokes.  The spokes may be thin tensile members (a.k.a wires) but now you've introduced another mode - out-of-plane motion of the wires, resulting in "pretzeling" of the toroid.

The way to kill that is to get the wires out of plane, and you end up with a (SURPRISE!!!!!) bicycle wheel.

Which I'll be perfectly fine with, ridiculous as it may look, but a hub you shall therefore have.

[Mackilroy]

Now we know where Vast is getting their financing: https://spacenews.com/vast-space-intro/

[su27k]

Now we know where Vast is getting their financing: https://spacenews.com/vast-space-intro/

Vast Space, a Southern California startup founded by scamcurrency billionaire Jed McCaleb, plans to establish an artificial-gravity space station in low Earth orbit.

McCaleb envisions a future where millions of people are living throughout the solar system. Since other companies are helping to reduce launch costs, McCaleb thinks the next important step will be creating large structures where people can live and work in space.

“Earth has finite resources, but out in the solar system, there is an enormous untapped wealth, both in terms of energy and matter, that could support many ‘Earths,'” McCaleb told SpaceNews by email. “Likewise, mankind needs a frontier. Every prosperous civilization has had one to push off into – nevertheless, we haven’t had one for some time. Without a frontier, the world becomes a zero-sum game, which is detrimental to the psyche of a civilization. And in terms of the long-term future of humanity, we will need to live off of the Earth eventually.”

McCaleb, whose wealth Forbes pegs at $2.5 billion, initially plans to self-finance Vast’s work.

[yg1968]

In the Commercial LEO Destinations procurement documentation (see below), NASA said that, in addition to zero-g, it was interested in artificial/partial gravity as a stretch goal. It will be interesting to see if Vast makes a proposal in the next round of the commercial LEO Destinations (CLD) program. My understanding is that the next CLD round will be a full and open competition, not a down selection of existing CLD providers. 

[...] Incidentally, here is what NASA had to say about the [artificial/partial gravity] Stretch service goals in its August 5th announcement:

2.2.4 “Stretch” Service Goals

In addition to evaluating the overall CLD goals listed above, NASA will also evaluate proposed CLD concepts for their ability to provide the following ancillary service capabilities listed here. Implementation of these goals should not impact the CLD’s primary goal to provide the services described in the sections above in a safe, reliable, and cost-effective manner. Optional or evolutionary approaches to support these stretch goals can be proposed along with approximate development costs. [...]

2.2.4.2 Artificial/Partial Gravity Services

Capability to perform up to human-scale artificial gravity research such as to simulate Moon and/or Mars surface gravity for experiments or as a countermeasure to the effects of microgravity on crew health and performance.

A bit of an update on phase 2 of CLD (i.e., the certification and services phase):

[...] After Axiom, Blue Origin, Nanoracks, and Northrop Grumman have matured their designs and business models over the next 3-4 years, NASA intends to have a second phase of activity whereby the Agency contracts with one or more entities to certify their designs as safe and to purchase services from the CLD provider(s). This second phase, which will be a full and open competition, is similar to the Commercial Crew transportation Capabilities (CCtCap) contracts NASA awarded to SpaceX and Boeing for the Commercial Crew Program. Thus, the Agency is building on the successful legacy of our commercial crew and cargo programs that are currently delivering important research, supplies, and NASA and international partner astronauts to the ISS.

https://www.nasa.gov/sites/default/files/atoms/files/2022_iss_transition_report-final_tagged.pdf

[lamontagne]

Why would it have 16 ring sections on one side and eighteen on the other?

[lamontagne]

Modelized it.
13 section with 3 rings each 2.7m tall, just a bit longer than 100m.
6m diameter each.

I don't understand why they group the solar panels the way they do.  It's an asymmetrical grouping, that works best if modules are designed 2 x 2.  Perhaps that is the case, as 2 modules are 16,2m long and would fit into an extended Starship?

For an unknow reason they station is not symmetrical, or has some rings that are higher than others.

The solar panel arrangement will go through an occultation period when they shadow one another.  Or perhaps it just doesn't spin like the ISS, but has fixed panels.  Simpler. 
2.6 or even 2.5 m floors would have worked as well.

[TrevorMonty]

Starting with small unmanned demo station maybe good place to start. Could be used for animal experiments like placing mice in lunar and Mars gravity for months at a time.
I'd imagine crew Dragon being used to visit station which would need to spin down.

[Paul451]

The solar panel arrangement will go through an occultation period when they shadow one another.

How do you figure? It would spin flat to the sun.

[lamontagne]

The solar panel arrangement will go through an occultation period when they shadow one another.

How do you figure? It would spin flat to the sun.

Ah yes, could do that.  For some reason, my mind had it spinning on the minor axis rather than the logical major one.

[Paul451]

The solar panel arrangement will go through an occultation period when they shadow one another.

How do you figure? It would spin flat to the sun.

Ah yes, could do that.  For some reason, my mind had it spinning on the minor axis rather than the logical major one.

Well, I mean it is spinning on the minor axis. The secondary and primary axis are in the plane of rotation. The minor axis points to the sun and it rotates around that.

(Unless my terminology is off.)

[Robotbeat]

Someone make a crappy MS Paint diagram or a napkin sketch that you take a picture of.