Space Elevator Development

[markbulmer]

Hey guys,

New to this forum. Just was researching some interesting things regarding space elevators: https://en.wikipedia.org/wiki/Space_elevator

It seems like the cost of launching to space is a lot and having a space elevator would reduce the cost of putting something into space for ~$20,000/lb to ~$200 a lb. Wouldn't having this kind of cost advantage to launches be worth developing an elevator-style launch system ?

[nacnud]

Yes space elevators could be cheaper, but they are basically impossible to build.

[Robotbeat]

Funny thing is that if you believe SpaceX's numbers, space elevators aren't even cheaper even if we had good enough materials. ITS tanker is supposed to achieve a tenth that cost, less than $20/lb to LEO.

If you got really good at chemical rockets like SpaceX proposes, it gives basically every alt-launch concept a run for its money.

[AncientU]

Funny thing is that if you believe SpaceX's numbers, space elevators aren't even cheaper even if we had good enough materials. ITS tanker is supposed to achieve a tenth that cost, less than $20/lb to LEO.

If you got really good at chemical rockets like SpaceX proposes, it gives basically every alt-launch concept a run for its money.

Even undercuts the cost of ISRU propellant production from the Moon... 

[russianhalo117]

Yes space elevators could be cheaper, but they are basically impossible to build.

It would function the same as a deorbit tether for a satellite if long enough.

[Chris Bergin]

Welcome Mark. Moved it out of general and made it a more specific title (everything's not about SpaceX )

Space Elevators are very 2005.

[colbourne]

Space elevators would be very slow. Probably only able to have one shuttle on the cable at once. Any material we can dream of means that they will be very heavy and this all has to be launched in to space before it can be used.
On Earth I see no future for them. On other smaller planets and moons they could be of use.

I do see a potential for rotating tethers (bolo) to pick up small craft and move them to different orbits.

[Robotbeat]

Welcome Mark. Moved it out of general and made it a more specific title (everything's not about SpaceX )

Space Elevators are very 2005.

Yeah, this is 2017. The only elevators we care about is this one that's one tangentially related to SpaceX:
http://forum.nasaspaceflight.com/index.php?topic=41017.msg1623401#msg1623401

[SEI]

Here is a new train of thought to come up
with a theoretical solution to a Space Elevator:



The aim of these brainstorm videos is to visualize
a potential solution to a Space Elevator.

As the videos progress, they build upon the previous videos
refining the content with new research and taking into account
feedback and comments.

Please subscribe and share with anyone you think may be interested
to contribute to this initiative.

[A_M_Swallow]

100 km - are you suggesting a space elevator or just a very tall tower?

Height is relatively easy it is orbital velocity that causes the difficulties. This is why the space elevator cables have their centre of gravity at GEO.

[SEI]

the 100 km first stage is just to put pay-loads higher up in the atmosphere.
(this 100 km might actually be lowered as the research progresses)
It then switches to the OPUM (ORBITAL PICK-UP MODULE) stage which act more
as pick up drones. Then to the SPACE DOCK, then to the SUMMIT.

This is still just the general concept, a lot of refinements still to come as the research
progresses

[Nibb31]

So you get your payload to 100km altitude with a speed of 0.

Now all you need is an orbital drone equivalent to a fueled Falcon 9 or Ariane to push your payload from 0 to orbital speed (without losing altitude).

How does this make the job any easier?

[scienceguy]

It would have more than a speed of 0 because the Earth rotates with the elevator.

[A_M_Swallow]

It would have more than a speed of 0 because the Earth rotates with the elevator.

The top of the tower would move at 1 revolution per day, same as the Earth's surface.

[SEI]

Yes, at the top of the 'FLOATING DOCKS', the OPUM or Orbital Pick-Up Module would have to hook the pay-load from it's orbital speed.
This is I think the hardest challenge to overcome. Having said that, I believe this is less of a challenge than achieving a 100,000km elevator cable.

Here are  a few of the thoughts that I will try and showcase in the next videos:

-the OPUM is separated into 2 with the 'pick-up' device accelerating ahead of the orbital speed and then
slowing down to allow for a certain pick-up time. This is a damper so that when the pay-load is hooked, there
is a dampening of the acceleration.
-A ramp at the FLOATING DOCK level that free-falls the pay-load which then accelerates along
a mag-lev rail. (bearing in mind the atmosphere is thinner and hence there is less air resistance)
-this rail (we're talking a few kilometers long here) has a curve that coincides with the OPUMs trajectory

The idea being that the pay-load is accelerated and the OPUM pick-up head is slowed down along similar trajectories..
When both are aligned which will probably be at a speed in the order of a few thousand kilometers per hour,
they can attach.

There is definitely a challenge there, no doubt.

[RonM]

Yes, at the top of the 'FLOATING DOCKS', the OPUM or Orbital Pick-Up Module would have to hook the pay-load from it's orbital speed.
This is I think the hardest challenge to overcome. Having said that, I believe this is less of a challenge than achieving a 100,000km elevator cable.

Here are  a few of the thoughts that I will try and showcase in the next videos:

-the OPUM is separated into 2 with the 'pick-up' device accelerating ahead of the orbital speed and then
slowing down to allow for a certain pick-up time. This is a damper so that when the pay-load is hooked, there
is a dampening of the acceleration.
-A ramp at the FLOATING DOCK level that free-falls the pay-load which then accelerates along
a mag-lev rail. (bearing in mind the atmosphere is thinner and hence there is less air resistance)
-this rail (we're talking a few kilometers long here) has a curve that coincides with the OPUMs trajectory

The idea being that the pay-load is accelerated and the OPUM pick-up head is slowed down along similar trajectories..
When both are aligned which will probably be at a speed in the order of a few thousand kilometers per hour,
they can attach.

There is definitely a challenge there, no doubt.

How does a 'floating dock' supposed to work, especially at 100 km? That's almost double the record for a high altitude balloon. Unless you have a very clever idea and have done an engineering study with numbers, this is just fantasy.

[SEI]

Yes RonM,

The numbers in this video are only a beginning of the brainstorm and I agree that 100 km is too high.
As I mentioned in my previous post:
'(this 100 km might actually be lowered as the research progresses)'

The idea behind this brainstorm is to adjust and build upon the skeleton I'm providing to hopefully come up with a theoretical solution. this is only video 003. The final video may come to a dead-end or may not look at all like this first draft of a proposed solution.
I call it a ping-pong game. Visuals are very helpful to understand what needs to be done. There are many unknowns and unanswered questions and a degree of fantasy. This is why I'm sharing it, to gather thoughts and come up with a solution.

Since this video was published, I have found out that the record for balloons is 53 km and that the optimal height potentially would be more around the 80 km mark. The floating technology that I'm interested in is the Airlander 50.

Of course, the tech that exists today is just a beginning of what will be required and probably just about every tech that will be needed to pull this off will be pushed to their limits.

Thank you for your comments and please feel free to post numbers and facts so that we can lock down what the realistic height of the FLOATING DOCKS should be.

[aceshigh]

it's not brainstorming if it's pure nonsense. Nor it is a space elevator if it's 100km high.

I think you entirely miss the concept of a Space Elevator. I also think you may not have a good clue of the difference between getting to space (and falling down as soon as fuel runs out) and reaching ORBIT.


Orbit is not about altitude. If Earth had no air (like the Moon) and was a perfectly smooth sphere, you could achieve orbit floating 1 meter above the ground. Or even 1 cm.

Orbit is about horizontal velocity. The ground must be getting away from you due to curvature at the same rate you are pulled towards it due to gravity.

[SEI]

aceshigh,

To begin with, the height of the FLOATING DOCKS will now be more around the 60-80 km mark. I've added
that as a comment on the video after feedback I've received.
I have failed to mention in video 003 that the FLOATING DOCKS will actually be supported by blimps.
They are meant to be floating balloons, hence the name. I will definitely address that in the new video to make sure there is no confusion, thank you.

The 'space elevator' name is more to stay in line with the existing concept of 'not using rockets' essentially.
I've labelled this a 'multi-stage approach elevator' for now as the ultimate goal is to get to space as efficiently as possible.

and FYI regarding where space begins:
https://www.popsci.com/where-does-space-begin?con=TrueAnthem&dom=tw&lnk=TATW&src=SOC&utm_campaign=&utm_content=5b1278c200bd4700073e9461&utm_medium=&utm_source=

[IRobot]

Sometimes I think we are just feeding Youtube conspiracy theorists/trolls/etc.