Going up! Japan to test mini 'space elevator'

[Still Waters]

A Japanese team working to develop a "space elevator" will conduct a first trial this month, blasting off a miniature version on satellites to test the technology.

The test equipment, produced by researchers at Shizuoka University, will hitch a ride on an H-2B rocket being launched by Japan's space agency from southern island of Tanegashima next week.

The test involves a miniature elevator stand-in—a box just six centimetres (2.4 inches) long, three centimetres wide, and three centimetres high.

If all goes well, it will provide proof of concept by moving along a 10-metre cable suspended in space between two mini satellites that will keep it taut.

The mini-elevator will travel along the cable from a container in one of the satellites.

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

[freetoroam]

Lets hope the typhoon has not put a stop to it...but saying that, i think Japan at this moment has more pressing issues on Earth.

[Mystify]

I Don't know, however to me, this sounds like outdated technology. Focusing on ships I think would be a lot safer and financially able.

[danydandan]

They'll need alot more than Viagra to keep that erect.

[Calibeliever]

I read Fountains of Paradise 35 years ago and I've been fascinated with this idea ever since. The technical questions (challenges) are numerous. How much does a 23,000 mile cable weigh? How do you attach it at both ends? If it's in segments how do you propose to work on the middle bits? How do you keep tension on it? And many, many more. Bradbury's book centers on a rescue mission to save passengers stranded halfway up the elevator and the challenges of reaching and working at those heights (arguably more difficult than getting into, and working in orbit).

"I don't think it's going to fly Orville..." -Wilbur

[L.A.T.1961]

If one could be built it would drastically reduce the costs of putting things in orbit but I think it will be a serious challenge to find and make a suitable material for the structure/cable.   

It might be easier to build a big rail gun inside a long vacuum tube and propel things into orbit with that, the technology is mostly available already ?   

[danydandan]

14 minutes ago, L.A.T.1961 said:

If one could be built it would drastically reduce the costs of putting things in orbit but I think it will be a serious challenge to find and make a suitable material for the structure/cable.   

It might be easier to build a big rail gun inside a long vacuum tube and propel things into orbit with that, the technology is mostly available already ?   

Or a giant slingshot?

Such an undertaking would be impossible technically, the wind alone would render the project impossible. Plus Japan has pretty unpredictable weather, earthquakes and typhoon's and such.

[XenoFish]

I still think using a linear accelerator type system would be better. 

[toast]

Quote

the company has said it could use carbon nanotube technology, which is more than 20 times stronger than steel, to build a lift shaft 96,000 kilometres (roughly 60,000 miles) above the Earth.

How could such a string be managed to not slice satellites?

[L.A.T.1961]

9 minutes ago, danydandan said:

Or a giant slingshot?

Such an undertaking would be impossible technically, the wind alone would render the project impossible. Plus Japan has pretty unpredictable weather, earthquakes and typhoon's and such.

 

It could be built in a stable geological area of the globe but Japan does have big transport systems that have to be earthquake proof. Super conducting magnets/coils could be used for propulsion.  

What is needed is something like this, but pointed up  

 

[keithisco]

50 minutes ago, Calibeliever said:

I read Fountains of Paradise 35 years ago and I've been fascinated with this idea ever since. The technical questions (challenges) are numerous. How much does a 23,000 mile cable weigh? How do you attach it at both ends? If it's in segments how do you propose to work on the middle bits? How do you keep tension on it? And many, many more. Bradbury's book centers on a rescue mission to save passengers stranded halfway up the elevator and the challenges of reaching and working at those heights (arguably more difficult than getting into, and working in orbit).

"I don't think it's going to fly Orville..." -Wilbur

I think it was Arthur C Clark that wrote Fountains of Paradise...what a great book that is!

Now, as then, we simply do not have a material with sufficient tensile strength to support its own weight up to a likely La Grange Point and this japanese experiment will not provide "Proof of Concept" as stated because it is nowhere near representative of conditions that a Space Elevator would need be built in. 

Quote

 

For want of an atom, the space elevator failed.

Carbon nanotubes (CNTs) are famed for being a future wonder material that will enable a swathe of super-strong but light applications from racing bikes to computer components.

But now it seems a single out-of-place atom is enough to cut their strength by more than half. That means one of the more outlandish applications for CNT fibres – a sci-fi space elevator – might never happen.

The tubes’ strength is a result of their atomic structure, with walls made from just a single layer of carbon atoms locked in a hexagonal grid. Theoretical studies suggest that a single CNT can have a tensile strength of 100 gigapascals (GPa), making it one of the strongest materials around, but efforts to spin multiple nanotubes into a practical large-scale fibre have only produced ropes with strengths of 1 GPa.

To find out why, Feng Ding of the Hong Kong Polytechnic University and his colleagues simulated CNTs with a single atom out of place, turning two of the hexagons into a pentagon and heptagon, and creating a kink in the tube. They found this simple change was enough to cut the ideal strength of a CNT to 40 GPa, with the effect being even more severe when they increased the number of misaligned atoms.

 

Source: New Scientist

[danydandan]

12 minutes ago, L.A.T.1961 said:

 

It could be built in a stable geological area of the globe but Japan does have big transport systems that have to be earthquake proof. Super conducting magnets/coils could be used for propulsion.  

What is needed is something like this, but pointed up  

 

It would need to be build upon thin and wispy spindles.

[XenoFish]

2 hours ago, danydandan said:

It would need to be build upon thin and wispy spindles.

https://www.newscientist.com/article/dn10180-huge-launch-ring-to-fling-satellites-into-orbit/amp/

[Calibeliever]

2 hours ago, keithisco said:

I think it was Arthur C Clark that wrote Fountains of Paradise...what a great book that is!

Now, as then, we simply do not have a material with sufficient tensile strength to support its own weight up to a likely La Grange Point and this japanese experiment will not provide "Proof of Concept" as stated because it is nowhere near representative of conditions that a Space Elevator would need be built in. 

Source: New Scientist

Doh! Of course it was... whadisay?  *sigh* Senior moment  

[keithisco]

17 minutes ago, Calibeliever said:

Doh! Of course it was... whadisay?  *sigh* Senior moment  

Dont beat yourself up...I was just having one of my lucid moments - at my age they become less frequent 

[Bunzilla]

5 hours ago, keithisco said:

Now, as then, we simply do not have a material with sufficient tensile strength to support its own weight up to a likely La Grange Point and this japanese experiment will not provide "Proof of Concept" as stated because it is nowhere near representative of conditions that a Space Elevator would need be built in.

My thoughts exactly. We all know that the idea could work in theory, but finding a material with a high enough tensile strength and the logistics of actually constructing the thing, none of that will be addressed with this test. I've always loved the idea, but a ten meter long test model won't do much. Wouldn't a computer model give more accurate results? You could plug in all the data about changing gravity and atmosphere, material strength, wind sheer, ground instability, etc.

Though I just thought of another problem. I believe part of the concept of space elevators was that one end would be in orbit and that would hold the thing taught and in place, but... I don't believe that anyone has actually managed to put anything into a stable orbit? Even our moon is slowly creeping away from us year after year. Meaning that the structure of the elevator would be under additional stress from either pushing back down or pulling away. Maybe that's me taking out of my ass?

[L.A.T.1961]

On 06/09/2018 at 9:48 PM, Bunzilla said:

My thoughts exactly. We all know that the idea could work in theory, but finding a material with a high enough tensile strength and the logistics of actually constructing the thing, none of that will be addressed with this test. I've always loved the idea, but a ten meter long test model won't do much. Wouldn't a computer model give more accurate results? You could plug in all the data about changing gravity and atmosphere, material strength, wind sheer, ground instability, etc.

Though I just thought of another problem. I believe part of the concept of space elevators was that one end would be in orbit and that would hold the thing taught and in place, but... I don't believe that anyone has actually managed to put anything into a stable orbit? Even our moon is slowly creeping away from us year after year. Meaning that the structure of the elevator would be under additional stress from either pushing back down or pulling away. Maybe that's me taking out of my ass?

I would think a computer model would be just as informative as this particular experiment.

A stable orbit for a space elevator is not necessarily required, if the terminus moved around it need not stop the system from working as long as it was within limits. From what I have seen discussed in the past points along the elevator would have control thrusters and these would keep the whole thing aligned. Thrusters would also allow some controlled snaking to avoid space debris or even satellites if required.   

[Bunzilla]

5 hours ago, L.A.T.1961 said:

I would think a computer model would be just as informative as this particular experiment.

A stable orbit for a space elevator is not necessarily required, if the terminus moved around it need not stop the system from working as long as it was within limits. From what I have seen discussed in the past points along the elevator would have control thrusters and these would keep the whole thing aligned. Thrusters would also allow some controlled snaking to avoid space debris or even satellites if required.   

But wouldn't having thrusters on such a large structure negate the positive aspects of a space elevator? I'm talking about having the end most likely come crashing back down to earth since that's what most manmade structures in orbit seem to do. Though I suppose thrusters at that end to keep it in place might indeed work. But we're still dealing with fuel consumption in that case. How often does the ISS have to use its thrusters to keep in orbit, and how much fuel does it use? It may still outweigh the negatives.

[L.A.T.1961]

On 08/09/2018 at 9:13 PM, Bunzilla said:

But wouldn't having thrusters on such a large structure negate the positive aspects of a space elevator? I'm talking about having the end most likely come crashing back down to earth since that's what most manmade structures in orbit seem to do. Though I suppose thrusters at that end to keep it in place might indeed work. But we're still dealing with fuel consumption in that case. How often does the ISS have to use its thrusters to keep in orbit, and how much fuel does it use? It may still outweigh the negatives.

The general idea is that the forces involved due to gravity and Earth's spin on the lift cancel out, so there is no thrust required to keep the structure upright. There would be tidal gravitational effects caused by the moon but it would not create enough movement to cause a collapse. Thrusters would be fitted at intervals along the lift's length and should only need to provide low thrust, mainly for station keeping.