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Japan To Test Mini 'Space Elevator' (phys.org)
Zorro shares a report from Phys.Org: 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 centimeters (2.4 inches) long, three centimeters wide, and three centimeters high. If all goes well, it will provide proof of concept by moving along a 10-meter 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. The movement of the motorized "elevator" box will be monitored with cameras in the satellites.
6cm long, 3 cm wide, 3cm high, works for Japanese, that's the average size of a Japanese apartment, but what about the rest of us?
Typical, don't waste a moment to think about those damn gaijins.
We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
Unless its running from the surface to space. Between two satellites in space is more of a "Space Conveyor".
They are materials science problems.
Newtonian physics does the job of predicting what will happen extraordinarily well and quite frankly you could do the experiment on earth, with a centrifuge apparatus and learn more, and cost less. Something like this https://www.roadsideamerica.co... if you want to test your cable climber but you don't even need that.
Only 2041990 meters to go!!
A ten meter tether is not a space elevator, and is not really anything like a space elevator.
Twenty kilometer tethers have already been demonstrated in space, notably the NASA Small Expendable Deployer System Experiments
(SEDS and SEDS II): http://www.daviddarling.info/e...
http://www.geoffreylandis.com
If we're talking about towers, I think some guy named Nimrod might have him beat by a few dozen centuries.
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Alright, so let's build this space elevator on the moon, then. Problem solved, once and for all.
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What exactly is the experiment meant to prove? Moving little devices over a 10 metre taut wire isn't exactly pushing the boundaries of science.
The problem is that CNTs are strong enough, if manufactured perfectly. Flaws in the manufacturing process, even ones that lead to only a few atoms being misaligned, reduce tensile strength by 100x or more.
Not clear. The predicted high ultimate strength of nanotubes is entirely theoretical, it has yet to be experimentally demonstrated.
Carbon nanotubes are strong enough in an idealized theory that doesn't allow bonds to shift. If you include the fact that the hexagonal rings spontaneously shift the bonds to form pentagonal rings or heptagonal rings under stress, they don't reach that ideal strength. It's not clear that you can stabilize the hexagon only structure.
https://www.newscientist.com/article/2093356-carbon-nanotubes-too-weak-to-get-a-space-elevator-off-the-ground/
http://www.geoffreylandis.com
We have a pretty good idea what will happen if we build it.
Yes: it will swing and bob wildy out of control, and eventually the counterweight will start zooming around the GEO station, if the station is massive. Then the cable will break and the counterweight will shoot off in a random direction, and inevitably destroy Tokyo.
The hard problem for a space elevator, even aside from needing unobtanium, is the lack of any way to damn the pendulum-like energy fed into the system with every payload lifted. Only half the energy needed to get to GEO is in lifting, the other half is in accelerating the payload laterally. That energy will be added to the system with every load lifted, and there's no obvious way to damp it.
And remember, this is not a Freshman Physics pendulum. It's both a spring pendulum and a double pendulum. Each of which is a chaotic system. When combined, it's a mess.
Socialism: a lie told by totalitarians and believed by fools.
"What is this, a space elevator for ANTS?!"
the preceding comment is my own and in no way reflects the opinion of the Joint Chiefs of Staff
Fun fact: the Moon-synchronous orbit height is actually closer to Earth than the moon.
Of course, we could just build it on Mars! Except, well, there's this damn moon that actually orbits lower than Mars-synchronous orbit, and our elevator would have to dodge it every few hours. But that's a minor problem for the engineers, let's not get side-tracked. Mars Elevator!
Socialism: a lie told by totalitarians and believed by fools.