US Patent 9085897: Space elevator
patft.uspto.gov
patft.uspto.gov
Also, is 30% of fuel costs really going to be worth it? According to [1] Elon Musk claimed fuel is only 0.3% of the cost of current rockets. Even if we assume SpaceX slashes the overall cost to 1/10th without touching fuel costs, that still only brings fuel up to 3%. 1% additional savings doesn't seem like it's going to do much to help finance a 20km tower.
Of course if single stage to orbit planes are viable from it, then that may make it more attractive, but it seems peculiar to focus on the fuel cost.
[1] http://www.space.com/21386-spacex-reusable-rockets-cost.html
E.g. consider that Musk a few years ago estimated the fuel and oxidizer costs for a Falcon 9 v1 at ca $200k per launch, with a list price for the launches at $54m to $59.5m. Cutting the cost of the rockets themselves on the other hand, whether by reuse or making them smaller/cheaper will matter much more.
I guess whether eliminating the first stage entirely vs. reuse will matter much will depend on how many times recovered stages can be reused and how much it will cost to prepare them for reuse, as the potential fuel savings are basically rounding errors.
3% to 30% is a 10x savings, because it's a ratio.
E.g., if it takes $1,000 of fuel to get a unit mass into orbit, then a 3% ratio means $33K, and a 30% ratio means $3K.
I am always skeptical of "massive upfront investment but lower per-unit costs," especially for space-launch. It's the way most of us learn about space, because sci-fi novelists talking about space have to explain what finally got man into space, and a massive infrastructure seems such a nice logical explanation. But Musk has shown that Plain Old Boring Rockets can be done much more efficiently than traditionally done. And that doesn't make a good sci-fi backstory.
If we assume that SpaceX cuts the overall cost of launches to 1/10th mainly by reuse of the first stage, that is indeed a 10x savings, but not on fuel (in fact, SpaceX uses more fuel because they need to be able to slow the first stage).
0.3% of x is the same as 3% of x/10.
So my point was that even with SpaceX numbers, where fuel will (once they sort out reuse) make up substantially more than what it currently does (because they're aiming to massively slashed the non-fuel costs), a 30% cut in fuel costs will "best" case cut launch costs by about 1%.
If these guys are going to achieve substantial cost cuts it will need to be elsewhere unless Musk' has been massively misquoted or is totally wrong about the relative cost of fuel vs. the rest.
(I'm not going to bother being precise as all of these are handwavy estimates from people anyway).
EDIT: Which has now been replaced by the patent application, for the general confusion of everyone...
[1] http://patft.uspto.gov/netacgi/nph-Parser?patentnumber=90858...
Edit: My mistake, I didn't realize that this wasn't the normal concept of tether out past geosync.
I agree 100% that the economic viability of a "space elevator" like this is basically non-existent, even though it's a really fun thing to think about.
Any lawyers able to comment?
The information contained in the disclosure of an application must be sufficient to inform those skilled in the relevant art how to both make and use the claimed invention. However, to comply ..., it is not necessary to “enable one of ordinary skill in the art to make and use a perfected, commercially viable embodiment ...”
The written description also has to be sufficient enough to show that you actually possess the invention when the patent is filed.
So technically, if this can't be built today because we don't know of any materials that can actually behave this way, it's not a valid patent.
I'm not totally sure what happens in cases where the invention is possible but so prohibitively expensive that it's not really possible. I'd imagine that is valid.
Traditionally, invalidating a patent based on written description or enablement issues was hard. But the Fed Circuit has made it easier in recent decades.
I'm pretty sure it wouldn't be valid, but I'm not familiar with the sort of building materials necessary to build a space elevator. My understanding is that nothing we have today could do it, but that's based on light reading.
EDIT: I'd also be willing to bet that some popscience mag or text book discloses this general idea anyway, so it'd be invalid based on prior art too.
The reason this contradicts your reading is likely because, as others have commented, it's not a real space elevator. It doesn't go to space, and it is more like a super-tall building with an interesting adaptive stability system than a tether connected to a counterweight as in traditional space elevator designs.
So this also means it may not be prior art. The innovation is located in however it is they plan to keep a 20km tall structure stable and attach an electric elevator for rockets to it.
I don't think a model is necessary for a patent application, but some check on bullshit is necessary. If you are granted the patent, and following the instructions in it does not yield a working device--or if the instructions cannot be followed, because they require an impossibility or something that does not yet exist--that should be grounds for immediate disqualification.
There has to be some way to encourage "this is how you do it" over "so I have this really cool idea that I think is worth lots of money".
Counterexample: designing TCP/IP was an expensive, R&D-intensive process, but it's pretty easy to write a TCP/IP stack given the RFCs.
The patent covers a pressurized space elevator tower.
However, note that the part they have really patented here is the "plurality of segments and pressurized cells" part. The claims were amended during prosecution, in light of the examiner rejecting them all as anticipated by various references :)
The way to discover this is to go to the USPTO's "public pair" system, enter the application or patent number, click "image file wrapper", and you can see all the correspondence between the examiner and the applicant. You are looking for the rejections and the amendment/claims parts that happened.
In response to this rejection, the applicant added the "divided into a plurality of segments along a length of the space elevator tower, each of said plurality of segments containing a plurality of cells defining a core, and a plurality of stabilization devices distributed along the length of the space elevator tower; wherein the plurality of cells are pressurized with a gas to support the pneumatically pressurized structure; and wherein said plurality of stabilization devices is configured to provide active stabilization of the space elevator tower using a harmonic control strategy." requirements in claim 1.
This means a space elevator tower which was not exactly this would not be covered in any way (because they have given up doctrine of equivalents by amending the claims).
That is just on it's face. In court, if someone came up with a reference for a space elevator with these features, it would be invalid there too ;)
"plurality of segments", "plurality of cores"
It's just describing building a tower using multiple sections which is in itself sub-divided. this sounds like a pure concept as well. And still very broad as they didn't specify the size of the sections. Nor did it specify what the stabilization devices are.
What do you mean by "pure concept" that's not a patent thing :)
Do you mean an abstract idea?
Because it isn't. It's a method of constructing a physical thing. "And still very broad as they didn't specify the size of the sections."
They don't have to, as long as it's possible to build it.
Again, your complaint seems to be the examiner didn't search hard enough to find references. This is not a simple problem to solve (Trust me, I have worked on it for years)
Also thanks for explaining to the HN crowd how to check the full folio. Reading patents became a lot easier when an IP lawyer showed me that years ago. It removes so much of the "wtf" from many of these "bullshit patents".
Instead of a vertical structure, as pretty much every single space elevator contains, why not make one that is tangential to the surface of the planet?
Yes, it will be substantially more materials, but if made such that the 'tail' of the elevator is trailing the rotation of the planet, it might be partially self sustaining. (Think of a string attached to the edge of a merry-go-round whipping outwards)
One would literally pick a point on the planet and build due west. Due to the curvature of the planet, after X number of miles, you'll be several miles up in the air.
Is this not anymore farfetched than a 100km tall tower?
One thing is that west, east, north, soyth up and down are really on relevant on earth. As soon as you are talking about space everything is up(or down) but in relaity regardless of which whay yo go to get there you are fighting against gravity. I assuem this would be the reason your idea would not work but i may be wrong.
There's no drag in space, so trailing Earth's rotation isn't necessary.
The orbital period of a satellite is set by its altitude. A lower orbit means a shorter period.
Since a geostationary satellite is one with an orbit above the equator and a period of 1 day, so its orbit matches the earth, and the period is set by the altitude, a geostationary satellite can only exist in one orbit. That's why the geostationary band is getting a bit crowded.
Not only is it far harder, but it doesn't take much length before even quite solid objects will start bending massively and exerting far more stress. E.g. doesn't take more than 150kg or so before the steel weight bars at my gym has a noticeable bend.
We still do not have materials technology advanced enough for a regular space elevator. Trying build one where gravity is actively working in a direction where there's no support seems unlikely to help matters.
I didn't necessarily mean a free-standing object that was anchored at only the base.
Another commenter pointed out a project very similar to what I was thinking: StarTram: https://en.wikipedia.org/wiki/StarTram
It has supports and launches the vehicle using maglev; basically a big, tangential, spaceship cannon that launches into orbit using fixed structures.
http://www.quora.com/How-feasible-would-the-catapults-from-t...
First off, the way stresses work it is substantially easier to build straight up than in any other direction.
And secondly, you're missing something. Namely, that the only reason why a string attached to an edge of a merry-go-round whips tangentially is because of air resistance. In a vacuum, or if the air was moving with the merry-go-round, the string would be radially-pointing. (There's also a component of "the merry go round is slowing down", but that also isn't particularly relevant.)
As such, it makes no sense to build something this way. About the only case where not building straight up would make sense is if you're slightly off of the equator - in which case you should move to the equator.
Although I suspect you have the wrong impression of a space elevator. You don't build up, you build down. You have a satellite / asteroid / etc in geosynchronous orbit. You start spooling out two lengths of wire - one down, one up. When the lower one reaches the surface, you anchor it. Then attach a counterweight out beyond geosynchronous orbit.
If it's close enough to earth, i think the cable will get some induced current, which could spin a gyroscope in the hammerhead, getting some angular momentum back.
Actually, i just wonder if this approach has a name, seems like every harebrained idea i've ever had was thought of fifty times before by much smarter people.
edit Skyhook! cool.
You are incorrect with your statement about "the way stresses work". The reason it is substantially easier to build straight up is due to our implicit basis where up is towards space. This is getting rather high level but stresses are actually tensors and hence are dependent on the chosen basis. If your basis has up pointed towards the north then it is substantially easier to build a different direction than up.
This may seem like a semantic argument but it is actually an extremely important distinction when discussing any tensor (position, velocity, stresses).
If you're on the moon, the idea makes a lot more sense in a lot of ways.
At 1km from the tangent point, you're only 8cm above sea level. At 10km, you're 8m above. So far, so good. At 100km, you're 784m up. At 1000km, that support is 78km tall.
The only economical way to do even part of it would be to build an evacuated acceleration track up the side of an existing mountain. The west face of Chimborazo in Ecuador is probably the ideal location for something like that. But you would need to accelerate at 23g for about 283km (51s) in order to reach escape velocity without any additional boost after the launch vehicle exits the track. That would be strictly for unmanned missions.
Accelerating at 3g for 283km (139s) to a height of 6268m above equatorial sea level would achieve 4080m/s, of an escape velocity of 11170m/s. You get 465 m/s for free by being near the equator. That leaves a delta-v of 6625 m/s. If your launch vehicle used RS-25 rocket engines, that means an extra 13% of your total launch vehicle mass can be cargo instead of propellant. The acceleration track would effectively substitute for the first stage of a rocket.
In order to reach escape velocity externally at 80 km above the equator (7850 m/s), you need 250 seconds at 3g (29.42 m*s^-2) of acceleration, which takes 1850 km. This is why the launch loop uses tethers instead of towers, and supports itself mainly with tension rather than compression.
But according to [0], there is also "constructive reduction to practice", which "occurs upon the filing of a patent application on the claimed invention."
That's not the same thing! Someone definitely got the meaning of those words mixed up.
And yes, I would love to see them try.
I think reduction to practice is still on the books but administratively ignored.
Edit: Oh, that's because it is not a space elevator...
Right?
"I have a great idea for this app, I just need a programmer to help me build it. No, I can't pay you, but I can give you 15% of the company!"