Japanese 2050 Space Elevator project (Obayashi Corporation)

[Grey Havoc]

One of the first news stories on it from February 2012:

Construction firm aims at space elevator in 2050
________________________________________________________________

The Yomiuri Shimbun

It may be possible to travel to space in an elevator as early as 2050, a major construction company has announced.

Obayashi Corp., headquartered in Tokyo, on Monday unveiled a project to build a gigantic elevator that would transport passengers to a station 36,000 kilometers above the Earth.

For the envisaged project, the company would utilize carbon nanotubes, which are 20 times stronger than steel, to produce cables for the space elevator.

The idea of space elevators has been described in several science-fiction novels. Obayashi, however, believes it is possible to construct one in the real world thanks to carbon nanotubes, which were invented in the 1990s, the company said.

Some other organizations have also been studying the development of space elevators, such as the U.S. National Aeronautics and Space Administration.

In Obayashi's project, a cable would be stretched up to 96,000 kilometers, or about one-fourth of the distance between the Earth and the moon. One end of the cable would be anchored at a spaceport on the ground, while the other would be fitted with a counterweight.

The terminal station would house laboratories and living space. The car could carry up to 30 people to the station at 200 kilometers per hour, which would mean a 7-1/2 day trip to reach the station. Magnetic linear motors are one possible means of propulsion for the car, according to Obayashi.

Solar power generation facilities would also be set up around the terminal station to transmit power to the ground, the company added.

Whether carbon nanotubes can be mass-produced economically enough and whether various organizations from around the world can work together are two key issues facing the development of the space elevator, according to the company.

"At this moment, we cannot estimate the cost for the project," an Obayashi official said. "However, we'll try to make steady progress so that it won't end just up as simply a dream."

(Feb. 22, 2012)


I should note that Obayashi Corporation was the primary contractor on the Tokyo Skytree, among other things.

[IMAGE CREDITS: DAILY YOMIURI ONLINE, DVICE], and Obayashi Corporation]

 

[PlanesPictures]

I'm not familiar with this project but there are there no noted problems. Due to different absolute speed on Earth surface and in height 36000 km you will need to have next source of energy to fix this problem. Do you know more about it?

 

[Bill Walker]

You need to include the force on the counter weight, above the space station. Google Space Elevator and read all about it.

 

[PlanesPictures]

Yes, it is noted there Coriolis power. But on start you will need to force counterweight to speed three times bigger as speed of terminal station and I think due to this Coriolis power counterweight will lost its speed and you will need still to force it with some rocket engine what is not calculated. But maybe yes. It is 40 years as I studied physic of plasma and probably I'm wrong

 

[Bill Walker]

Google shows this site,and many others with all the equations.

Another source suggests construction should start from geosync orbit, with one cable being lowered and one extended, at the same rates and mass distributions.

 

[ouroboros]

Big japanese construction conglomerates/general contractors like to periodically issue press releases with sweeping strategic visions of major infrastructure projects, largely because they are addicted to government infrastructure contracts like crack addicts and don't stand well on their own. So, in order to justify their continued existence, their comprehensive planning departments like to do extended thought exercises and throw it as easy PR fodder to maintain a claim of technical competence. If there was real movement, there would be declarations of a development office being set up, real money figures being spent on research, or announcements of recruiting older university professors to add legitimacy. That's not to say that it is a totally empty promise, as sometimes some necessary basic research gets some support funds. But there is less blue sky corporate sponsored research in japan now, though arguably more than many countries. Unfortunately, that is a byproduct of the short term capitalist thinking of US MBA's filtering back to japanese managers.



I would be more interested in the smallsat/nanosat/cubesat market developing in japan right now. There seems to be a potential fight for slots on the 2014/2015 Dnepr launch amongst japanese research groups as well as civilian companies, though usually only single satellites, no clusters at present such as Skybox's announced remote sensing cluster, but at least one for-profit weather forecasting service (weathernews) will be launching an arctic weather watcher (WNISAT-1) for selling arctic circle/northwest passage navigation information to shipping companies, which intends to be on the Dnepr launch.

 

[OM]

...Carbon Nanotubes are to Space Elevator enthusiasts what Gamma Interferon was supposed to be to Cancer Research: Unobtanium obtained.

 

[Grey Havoc]

http://www.youtube.com/watch?v=Kl083LAYnoU

 

[Grey Havoc]

http://www.abc.net.au/news/2014-09-21/japanese-construction-giants-promise-space-elevator-by-2050/5756206

http://asia.nikkei.com/Tech-Science/Tech/Shizuoka-University-s-space-elevator-test-concept-gets-go-ahead

http://the-japan-news.com/news/article/0001568374


Can we please move this topic back to space projects?

 

[blackkite]

Hi!
http://www.obayashi.co.jp/news/news_20130730_1

Can we discharge liquid CO2 (generated from fossile fuel power station) and high-level radioactive wastes effectively to the space by this machine?
The price of the construction cost of this elevator is 2 trillion yen per set.
Perhaps it is necessary to make a lot.
We can apply Solar power and Kinetic Energy-Recovery System to this machine.

 

[Grey Havoc]

https://phys.org/news/2018-09-japan-mini-space-elevator.html

https://gizmodo.com/japan-testing-miniature-space-elevator-near-the-interna-1828800558

 

[publiusr]

Another concept

buckle up - here’s an elevator that can transport travelers and cargo from ocean to space

www.designboom.com

 

[Nik]

Sadly, like economical Fusion power, the necessary cable material, in lengths beyond 'cubit', still seems to be several decades away...

And then there's the 'elephant in the room', the asteroid counter-weight...

First, catch your asteroid....

Or, hey, you could build it from mined lunar rock using mag-lev catapult system ??

 

[Scott Kenny]

I tried to get in on this, I was in Japan doing my study abroad year when it was announced.

Obayashi Corp didn't want a tame gaijin for whatever reason. Which is a real shame, one of my Professors at the time was hugely into Solar Power Satellites and was well known in the field.

Sadly, like economical Fusion power, the necessary cable material, in lengths beyond 'cubit', still seems to be several decades away...

And then there's the 'elephant in the room', the asteroid counter-weight...

First, catch your asteroid....

Or, hey, you could build it from mined lunar rock using mag-lev catapult system ??

One of the construction proposals I've read has the tether start to be lowered from a pretty low altitude. and then you lift the tether up as it grows. Not sure about the practicalities of that.

If your orbital station at geostationary altitude is massive enough and has that center of mass slightly above the true Geostationary altitude, you don't need much mass in the counterweight and can make the upper tether whatever length and mass you want.

Even with a truly balanced station with the center of mass right at GEO, if you run the counterweight cable out to 72,000km altitude you need a tiny counterweight at the end.

In all honesty, a bigger question is where on earth would you anchor the beanstalk? It needs to be on the equator. It needs a good 20km of space IIRC east of the location for a failed bit of cable to crash land in an emergency. You also want it as high as possible in the atmosphere to reduce tower base construction costs, but that's an option if you want beanstalk crashing down on land.

Equador and the Coast of Brazil. east Coast of Africa. Indonesia. Or build your own island.

 

[klem]

Article in french "The Space Elevator" by Christophe Bonnal (Centre National d'Etudes Spatiales. CNES), published in Revue "LETTRE 3Af" N° 40 Nov.Dec -2019.pp23-35 - La Revue de la société savante de l'Aéronautique et de l'Espace - Association Aéronautique et Astronautique de France.The Author summarizes the question and its problems.

 

[Orionblamblam]

And then there's the 'elephant in the room', the asteroid counter-weight...

That's not the problem. Capturing an asteroid is a comprehensible, answerable question; we know how to do it. It'd just be expensive.

The actual problem: how does the elevator climb the cable? In most feasible designs the cable is something like a ribbon a few mm thick and maybe 10 cm wide at the base, slowly transitioning to a circular cross-section a meter or more in diameter at the top. The cable is incredibly smooth, and carbon nanotubes are damn near frictionless. You can't grab it with anything. If you embed "texture" into it so cogs or wheels can get some sort of purchase, the weight goes through the roof. If you embed bits of iron so an electromagnetic system can grab hold, weight goes up even more. And whatever the system, it has to handle grabbing a cable that changes cross sectional area by several orders of magnitude.

 

[martinbayer]

That's not the problem. Capturing an asteroid is a comprehensible, answerable question; we know how to do it. It'd just be expensive.

The actual problem: how does the elevator climb the cable? In most feasible designs the cable is something like a ribbon a few mm thick and maybe 10 cm wide at the base, slowly transitioning to a circular cross-section a meter or more in diameter at the top. The cable is incredibly smooth, and carbon nanotubes are damn near frictionless. You can't grab it with anything. If you embed "texture" into it so cogs or wheels can get some sort of purchase, the weight goes through the roof. If you embed bits of iron so an electromagnetic system can grab hold, weight goes up even more. And whatever the system, it has to handle grabbing a cable that changes cross sectional area by several orders of magnitude.

Hello Scott, thank you for using metric units - I salute you, Sir.

 

[publiusr]

I’d want practice with a lunar elevator first.

 

[Orionblamblam]

Hello Scott, thank you for using metric units - I salute you, Sir.

On occasion they are useful. Past few days, though, when it's been -20F and we've gotten a few feet of snow, each shovel-full weighing twenty pounds... not so much.

 

[Orionblamblam]

I’d want practice with a lunar elevator first.

Not much point in such a thing. Lunar orbit can be achieved in a single stage using rockets fueled by lightly processed *dirt.*

 

[Scott Kenny]

That's not the problem. Capturing an asteroid is a comprehensible, answerable question; we know how to do it. It'd just be expensive.

The actual problem: how does the elevator climb the cable? In most feasible designs the cable is something like a ribbon a few mm thick and maybe 10 cm wide at the base, slowly transitioning to a circular cross-section a meter or more in diameter at the top. The cable is incredibly smooth, and carbon nanotubes are damn near frictionless. You can't grab it with anything. If you embed "texture" into it so cogs or wheels can get some sort of purchase, the weight goes through the roof. If you embed bits of iron so an electromagnetic system can grab hold, weight goes up even more. And whatever the system, it has to handle grabbing a cable that changes cross sectional area by several orders of magnitude.

So your manufacturing process needs to add an occasional piece of non-carbon for chemical bonds outside the tube. Relatively trivial in comparison to making a single molecule 36,000km long.

As to the shape of the cable changing, you don't climb the load-bearing cables directly. You climb up a track attached to the cable. Yes, this adds weight, but that just means you use a heavier counterweight.

 

[Orionblamblam]

As to the shape of the cable changing, you don't climb the load-bearing cables directly. You climb up a track attached to the cable. Yes, this adds weight,

It adds a *lot* of weight. One kilo per meter adds 100,000 kilos to the first 100 kilometers. If you can get it down to 10 grams per meters, you've added about 360,000 kilos to geosynchronous. This is all parasitic weight on the cable, adding no tensile strength.

 

[Prophet141]

I tried to get in on this, I was in Japan doing my study abroad year when it was announced.

Obayashi Corp didn't want a tame gaijin for whatever reason. Which is a real shame, one of my Professors at the time was hugely into Solar Power Satellites and was well known in the field.


One of the construction proposals I've read has the tether start to be lowered from a pretty low altitude. and then you lift the tether up as it grows. Not sure about the practicalities of that.

If your orbital station at geostationary altitude is massive enough and has that center of mass slightly above the true Geostationary altitude, you don't need much mass in the counterweight and can make the upper tether whatever length and mass you want.

Even with a truly balanced station with the center of mass right at GEO, if you run the counterweight cable out to 72,000km altitude you need a tiny counterweight at the end.

In all honesty, a bigger question is where on earth would you anchor the beanstalk? It needs to be on the equator. It needs a good 20km of space IIRC east of the location for a failed bit of cable to crash land in an emergency. You also want it as high as possible in the atmosphere to reduce tower base construction costs, but that's an option if you want beanstalk crashing down on land.

Equador and the Coast of Brazil. east Coast of Africa. Indonesia. Or build your own island.

Ascension Island is another choice.

Or there's another idea I've seen somewhere; have multiple elevator cables, but the average centre of mass is above the equator. So if you have two cables in the Northern hemisphere, you'd have a third twice the distance (or something like it) down in the Southern Hemisphere.

However, I imagine that in many instances artificial islands will be necessary, if only to act as a counter-balance to a cable on the opposite hemisphere.

 

[edwest4]

NSS Co-Sponsors Space Elevator Academic Challenge 2024 – NSS

nss.org

 

[Scott Kenny]

It adds a *lot* of weight. One kilo per meter adds 100,000 kilos to the first 100 kilometers. If you can get it down to 10 grams per meters, you've added about 360,000 kilos to geosynchronous. This is all parasitic weight on the cable, adding no tensile strength.

Yes.

But with orbital elevators you need to stop thinking Every Gram Counts when the station at GSO weighs in on the order of 100,000,000 tons and you're running literal freight trains of 10,000tons cargo up and down the beanstalk. (well over 1 million tons of that is water for drinking and shielding.)

Ascension Island is another choice.

7deg56min S, almost 8 degrees below the Equator. I'm not sure what the tolerances are for a GSO tether.

Or there's another idea I've seen somewhere; have multiple elevator cables, but the average centre of mass is above the equator. So if you have two cables in the Northern hemisphere, you'd have a third twice the distance (or something like it) down in the Southern Hemisphere.

Might be viable but would be complex geometry.

However, I imagine that in many instances artificial islands will be necessary, if only to act as a counter-balance to a cable on the opposite hemisphere.

Maybe.

 

[Orionblamblam]

Yes.

But with orbital elevators you need to stop thinking Every Gram Counts when the station at GSO weighs in on the order of 100,000,000 tons and you're running literal freight trains of 10,000tons cargo up and down the beanstalk.

Yeah... no. Right now, cables at the bleeding edge of maybe possible *might* be able to support their own weight. Maybe. Loading thousand-ton elevators onto them? Nah. Not there.

Bonus round: Let's say we've gotten there, cable can support a 10Kton elevator. Yay! How do you attach a *destroyer* to a frictionless, featureless cable the size of a checkout line conveyor belt? If you say "additional track elements," how heavy is this track that you can clamp a naval vessel to?

Bonus bonus round: what is the mechanism to drag a destroyer up this track at high speed? No, really... how do you do it? A propulsion system no more than a foot wide, by arbitrarily long, that can hold onto thousands of tons and drag it uphill at hundreds to thousands of miles an hour?

 

[PFJN]

Hi,
I should take a look at some of the links to see if things have changed, but I know that in the past when I have read about this kind of stuff alot of the calculations convenintly have neglected stuff like "factors of safety" and non-primary loads, such as wind shears, fatigue, wear and tear, and object strike, when trying to show the potential "feasibility' of this type of concept.

As such, I'm still waiting to be convinced about whether this will really be all that practical

Pat

 

[edwest4]

Complete with drawings and the math:

https://control.asu.edu/Publications/2020/Peet_AST_2020.pdf

 

[Orionblamblam]

neglected stuff like "factors of safety" and non-primary loads, such as wind shears, fatigue, wear and tear,

And oxidation. If the cable is made out of graphene, that means it's solid carbon, which will *burn* under the right conditions. Those conditions might include things like "lightning strikes." Remind me... are there storms on the equator? Could you build up some sort of static charge in a vertical rod that reaches from the ground to *above* the clouds and happens to be as electrically conductive as copper?

Sure, sure, put a weather coating on it. What sticks to graphene? I dunno. Paint? Teflon? Polyethylene?

 

[publiusr]

Not much point in such a thing. Lunar orbit can be achieved in a single stage using rockets fueled by lightly processed *dirt.*

True enough...but what are the electrical effects of a long cable.

Use existing materials for lunarvator...and see what deployment mechanisms work...if one fails...it is no LEO threat.

 

[Scott Kenny]

Yeah... no. Right now, cables at the bleeding edge of maybe possible *might* be able to support their own weight. Maybe. Loading thousand-ton elevators onto them? Nah. Not there.

Isn't that why the orbital elevator is under tension, not under gravitic compression? Things are usually much stronger in tension than under compression.

Also, if you can't load a train onto the beanstalk, there's zero case for building one. The whole point of a beanstalk is so that you can get cargo into and out of orbit for pennies a kg, not thousands of dollars per kg.

Bonus round: Let's say we've gotten there, cable can support a 10Kton elevator. Yay! How do you attach a *destroyer* to a frictionless, featureless cable the size of a checkout line conveyor belt? If you say "additional track elements," how heavy is this track that you can clamp a naval vessel to?

chemical engineering the cables so that they're not actually frictionless. Add something (I'm not enough of a chemist to know what) to the carbons in one spot of the carbon chains to give something for chemicals to hang onto without completely making a hash of the hexagonal ring structures.

Yes, there's probably a Nobel Prize in either Chemistry or Physics for figuring out how. But that's how I'd go about it. There's definitely another Nobel Prize in Engineering for figuring out how to make a single continuous molecule of nanotubes that is 36,000km long. "Monir details"

Bonus bonus round: what is the mechanism to drag a destroyer up this track at high speed? No, really... how do you do it? A propulsion system no more than a foot wide, by arbitrarily long, that can hold onto thousands of tons and drag it uphill at hundreds to thousands of miles an hour?

I was assuming linear motor maglev, using the train going down to provide power for the train going up, plus needing a little bit extra due to losses. So every 100km or so is a generator substation. And top speed of only about 300kph, since otherwise the vibrations get outside the limits of what the beanstalk materials can withstand.

 

[Prophet141]

7deg56min S, almost 8 degrees below the Equator. I'm not sure what the tolerances are for a GSO tether.

Oh, I misremembered its position.

I haven't seen anybody in any scientific literature complaining about the friction, but apparently a concept from 2000
In 2000, from Bradley C. Edwards suggested using a ribbon instead of a round cable to increase the surface area available for the climber. The Nasa Institute for Advanced Concepts (NIAC) picked him up and his work envelope was "expanded to cover the deployment scenario, climber design, power delivery system, orbital debris avoidance, anchor system, surviving atomic oxygen, avoiding lightning and hurricanes by locating the anchor in the western equatorial Pacific, construction costs, construction schedule, and environmental hazards."

Oh, and in case anyone hasn't heard of him:

View: https://www.youtube.com/watch?v=dc8_AuzeYKE

View: https://www.youtube.com/watch?v=0g4TZbG2WsU

 

[Prophet141]

Regarding having something to grab onto, I talked with someone who's more knowledgable on this stuff than I, and he suggested that, since you'll likely be using a large arrangement of cables, you can make a rope out of it. Into this rope you can insert bars, preferably of a similarly strong material as graphene to save weight.



Then, to prevent angular slip you simply add some bracers.
These bracers could also be graphene (and as such could also provide tensile strength). Alternatively, you might be able to have two cables with graphene bars between them, rather like a ladder with the bars being the rungs and the vertical struts being load-bearing.

Hopefully this setup would at least be able to support some of its own mass, especially if the bracers are also load-bearing.

Whatever mechanism ends up being chosen for this kind of project, I'm excited.

 

[Orionblamblam]

Isn't that why the orbital elevator is under tension, not under gravitic compression? Things are usually much stronger in tension than under compression.

A tether that reaches from the ground to GEO is under *spectacular* tension, and the latest in theoretical materials are the the first that can *maybe* withstand that... and that's tension just of the weight of the tether. Adding additional weight adds additional tension.

I was assuming linear motor maglev, using the train going down to provide power for the train going up, plus needing a little bit extra due to losses. So every 100km or so is a generator substation. And top speed of only about 300kph, since otherwise the vibrations get outside the limits of what the beanstalk materials can withstand.

Powering the elevator is a trivial problem compared to the tether itself: just point a laser at it.

 

[Justo Miranda]

The space elevator was just a senile occurrence of Clarke's at one of his worst moments.

 

[Prophet141]

That's just blatantly false since the concept of a tensile space elevator originated in 1959, and the idea of a compressive space tower from even earlier on in 1895.

Nice bait.

 

[PFJN]

Complete with drawings and the math:

https://control.asu.edu/Publications/2020/Peet_AST_2020.pdf

Hi,
Thanks for the link. It's an intresting paper. Though, looking through the document it seems to be more focused on physics of etrajectoris and orbits and such than structural requirments and design., so it doesn't appear to help in addressing some of design requiremnt concerns that much (such as material properties and design loads etc).

Regards

Pat

 

[Scott Kenny]

A tether that reaches from the ground to GEO is under *spectacular* tension, and the latest in theoretical materials are the the first that can *maybe* withstand that... and that's tension just of the weight of the tether. Adding additional weight adds additional tension.

And if you can't run 100 car freight trains plural up and down the beanstalk, there's no point in making a beanstalk. We'll all just ride Falcon Heavies or Supers into orbit instead.

And not just one train running 10,000 tons of cargo up and a second one running down, I'm talking about at least one train a day each direction on an assumed travel time to GSO of 120 hours. 10 trains on the beanstalk, 100ktons of cargo on the move. And probably 3-10x that weight in total train weight.

Powering the elevator is a trivial problem compared to the tether itself: just point a laser at it.

Microwave, lots less power conversion losses. But does happily remove the need for hanging power station on the beanstalk.

We won't talk about the scuttling charges at 100km to shear the tether when muggles are around to get scared.

 

[RanulfC]

Yeah... no. Right now, cables at the bleeding edge of maybe possible *might* be able to support their own weight. Maybe. Loading thousand-ton elevators onto them? Nah. Not there.

Bonus round: Let's say we've gotten there, cable can support a 10Kton elevator. Yay! How do you attach a *destroyer* to a frictionless, featureless cable the size of a checkout line conveyor belt? If you say "additional track elements," how heavy is this track that you can clamp a naval vessel to?

Bonus bonus round: what is the mechanism to drag a destroyer up this track at high speed? No, really... how do you do it? A propulsion system no more than a foot wide, by arbitrarily long, that can hold onto thousands of tons and drag it uphill at hundreds to thousands of miles an hour?

You move the "destroyer" the same way you eat an elephant, one bit at a time
(That's actually the main point at you can't move the whole thing in one go it has to go in pieces)

And keep in mind it's NOT "one" tether but somewhere near a half to a full dozen so you can have traffic going both ways.

Randy

 

[Orionblamblam]

And if you can't run 100 car freight trains plural up and down the beanstalk, there's no point in making a beanstalk.

Yes? If you can't have Supermans super-strength and ability to fly, you won't.

If beanstalks don't work, they don't work. And so far, they're interesting theoretically, but the engineering is extremely lacking.