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SpaceX Is Building a Hyperloop Test Track
Jason Koebler reports that SpaceX is building a small-scale version of Elon Musk's hyperloop transport tube system, which can move cargo and people at speeds over 700 mph. The test track will be approximately one mile long, and its inner diameter will be between four and five feet. But while SpaceX is building the track, it's not going into full development mode. Instead, the company is turning it into a competition. Other organizations will be invited to build pods — the containers that move through the tubes — and test them inside the track. They say the competition will be geared toward university students and independent engineering teams. SpaceX expects the testing to happen next June, and they've published a document with details on the competition. They add, "The knowledge gained here will continue to be open-sourced."
We should totally avoid testing on humans ... so I propose lawyers and sales people for the full acceleration/deceleration tests.
Because I'm betting this has the potential to liquefy the humans inside it.
Lost at C:>. Found at C.
1. All the diagrams give the impression that it will be like people flying through tubes as in Futurama. Instead you will be sealed inside a metallic "bullet", that runs in a metallic tube - no windows for you (sort of like James Bond in The Living Daylights). It's a pity if you have any sort of claustrophobia.
2. While the device doesn't run in a complete vacuum, it runs in an atmosphere that is low to the point of being unbreathable. But the device doesn't contain any onboard air supply - instead it relies on the driving compressor/fan assembly to compress the air to a human sustainable amount. So if the device loses power for any reason (electrical, mechanical, computational) then you better be able to hold your breath for a long long time.
3. There was no indication that the loop itself was anything more than a single tube. Thus there is no capability to bypass any section. So if a device fails, all devices that are already in transit and behind it are screwed (see 2 above).
I am Slashdot. Are you Slashdot as well?
1) It's not a vactrain. It's not even that similar to a vactrain. It functions like a very high altitude aircraft, with such rarified air (and the ground-effect surface for lift) being provided by a tube. Nothing is "sucking" or "pushing" it, and nor is it maglev. The compressor at the front exists to stop a column of higher pressure air from building up in front of it, not for propulsion.
2) It is not a train. Rates for building train tracks, rail bridges, etc, are not applicable. Of human structures it's most similar to, an oil pipeline is the most apt comparison - very long, continuously welded elevated tubular steel segments capable of withstanding a pressure differential. It has some disadvantages versus a pipeline, such as much tighter tolerances, as well as some advantages, such as not containing environmentally-hazardous flammable materials. A full comparative list is too long to go into at the moment.
3) Like a pipeline and unlike rail, costs for elevating it are significantly reduced because it doesn't experience wide load swings. The cars are an order of magnitude lighter than a high speed train and thus exert an order of magnitude less loading as they pass (and only briefly). The difference in throughput is compensated for by much higher launch frequency via computer control. With dramatically reduced loading comes dramatically reduced support structure costs - more akin to the supports on the Disney Monorail than that of a rail bridge.
4) It is not meant (as per the source) to be an exact replacement for rail; it's meant to be an intermediary transportation system between rail and air travel.
5) Yes, the original design has flaws. No, none of them are fundamental. Yes, the concept can be significantly improved upon.
Back to your regularly scheduled thread.
"99 dead duelists of Dios on the wall. 99 dead duelists of Dios! Take one's ring, pass it around..."
I wouldn't walk a mile for a Camel what makes Musk think I'd put a Logan's Run choo-choo in his tube?
On the other hand, whether a successful trip or not, it won't last long.
that Elon was going to name it the Ted Stevens memorial hyperloop
Harrison's Postulate - "For every action there is an equal and opposite criticism"
Perfect opp for side business. Buy/rent a Cardboard rig at the terminal and make pretend you're anywhere you wish.
"Win treats sysadmins better than users. Mac treats users better than sysadmins. Linux treats everyone like sysadmins."
Although the hyperloop is possible and might even be practical someday, let's please be honest about the reason it was created. Elon Musk just wanted to kill the California high-speed rail.
That might have been OK if there was a hope that we could actually replace it practically with a hyperloop. But given the history of bleeding-edge rail - ride any maglevs lately? We haven't even had much success with monorails outside of theme parks and Las Vegas - we don't really have any working system to replace high-speed rail. Hyperloop should really be called "Pipes that carry People" and we need decades of work on it before considering intercity lines.
Bruce Perens.
Sooo, they expect some jurisdiction to allow putting passengers in an evacuated tube, without full spacesuits? And in a steel tube, without exits? We shall see what state allows this stretch of the safety rules. Even the military doesn't allow folks to go up to 60,000 feet without a full spacesuit.
Interesting comment. It seems to me people in this country don't have the culture or mindset for high speed rail. In US especially California they are trains of railroad tracks that great grandpa built with grade crossings (problems of cars getting hit by trains, people committing suicide). In other countries HSR are systems (and there are no RR crossings, roads and walkways either go over or under). And then there is the "government is the problem!" bitching while infrastructure continues to deteriorate in this country. I don't see private companies stepping in to fill what needs to be done (except for exclusive areas, not region wide).
Though there are many supporters of HSR in high places, I get suspicious they're mostly motivated for profit (huge construction contracts). I also have email subscription to USHSR, I notice a complete lack of any kind of ASCE participation in all their conferences (maybe they have representation, I haven't find them). But occasionally USHSR puts out some insightful comments such as this:
"Congress members who continue to block funding for high speed rail are increasingly being seen as preventing progress and solutions to the nation's problems. These members of Congress can even be viewed as un-American sitting doing nothing as the nation suffers with our deteriorating transportation systems."
Though Musk's concept is interesting, can it be scaled to cover everywhere? and not just choice places that has business?
mfwright@batnet.com
Elon Musk just wanted to kill the California high-speed rail.
if it weren't so laughably or desirably easy to do this, you would have a point.
Let's take a look:
* the founder of Paypal, largest digital payment system;
* and SpaceX, the company to be the first to land rocket stages backwards cutting launch costs to 10% what they were before;
* and Tesla, the only electric car company to actually make it, much less thrive
says he can do it again for much cheaper.
I, for one, welcome our new John Galtian overlord.
Hey, I hang out with a lot of creative people. Not Elon Musk, but Steve Jobs for more than a decade, and lots of people at least as smart that you don't know. They can be really brilliant, and successful, and they can still make really stupid mistakes and sell them to the rest of us pretty well because they believe in themselves completely and they have a track record. I've done that too.
That's the hyperloop. Something Elon never meant to stand behind (and still really isn't), just put out there to torpedo a worthy project that he didn't believe in.
Anyone who looks at the hyperloop design can see it's not a no-brainer. It has safety issues up the wazoo :-) It's going to take a long time to get right.
Meanwhile, little Switzerland can have incredible trains everywhere and the United States can't get it together, and unlike with rockets and cars Elon's not helping this time. And I am not sure that the "lease" part of his solar business is a great thing for the world either.
Bruce Perens.
... you've got a dead engineer and a runaway train that's going to hit Chicago in 15 Minutes. Now what are you going to do about it?
1. An airliner is a VERY thin-walled aluminum tube full of people that is flung through the sky at altitudes where the air is so cold and thin that it is (to quote you) "to the point of being unbreathable". The windows in the wall of the aluminum tube airliner actually introduce added structural weakness as a trade-off to let the passengers feel less claustrophobic - the designers of the planes would prefer to leave them out of the designs.
2. Airliners do not contain big bottles of compressed air for the passengers, but rather rely on compressors driven by the engines to compress the otherwise too-thin outside air to make it suitable for the passengers - an idea you for some reason find completely unacceptable for Hyperloop,
3. Airliners also have only the single tube, held up by a single wing and stabilized by a single tail, so if any of these single structures fail its passengers are similarly screwed.
For Hyperloop, all that is required is a reasonable selection of simple safety mechanisms. For example, the equivalent of a "tow capsule" to be launched into the tube to push or pull a failed capsule to the next or previous terminal could deal with certain failure modes (the oil industry has unmanned capsules it can launch though an oil pipe when needed, so this is hardly a new idea). Another obvious way to deal with something like pressure loss in a capsule would be drop-down masks like on an airliner combined with a system to allow outside air into the loop if a capsule fails (which would have the simple physics-driven effect of slowing all the other capsules in the same tube). As with ANY high-tech system with lives on the line, the first rule is good design practice, the second rule is good manufacturing, the third is proper operation, and the final is well thought out safety systems. Hyperloop will be far easier to make safe than many other systems we use every day all over the world.
why is the lease part of solar city NOT a good thing?
I prefer the "u" in honour as it seems to be missing these days.
Hmmm.
Why the lack of monorails? Because of lobbying. Not because of engineering or superiority. Monorail IS cheaper and superior to any of the twin rail systems. The real issue is that twin rails were established in nearly all nations over 100 years ago. So, it is hard for Monorail to gain traction, esp when there are multiple designs.
Now as to hyperloop, it really has the only design that can make it cheap to build and safe.
You say that it is not safe, when the exact opposite is true. They are looking at electrical storage on-board. That enables the air compressors work, just like they do for jets. IOW, a pressurized container is no big deal because we have been doing this for over 60 years (all aircrafts that fly at 15K and higher).
It should be easy enough to either provide side-outs, OR even better would be to provide for 3 tunnels in which the 3rd can be used for bi-directional traffic (i.e. when traffic is much heavier in one direction, then use 2 tubes) or as a back-up. If a car develops an issue, then it is possible to stop 1 tube and re-pressurize it. With the 3rd tube, it is either not being used, it is already going in the same direction, or it is being used in opposite direction. If it is the later, then you have to wait for that tube to clear out before using it for the new direction. And if this moves at 700 miles / hour, and there is 'stations' every say 70 miles (i.e. 10 minutes), then issue solved.
Plenty of issues to solve, but I think that hyperloop really is a smart way to go.
I prefer the "u" in honour as it seems to be missing these days.
No aircraft ever had to come anywhere remotely close to pressurizing air from 0.1% (one millibar) to about 75% (what you need in a cabin when not using breathing apparatus). The Concorde had to pressurize from 7.5%. Typical airliners of today pressurize from about 25%. This is a hell of a lot further from the Concorde than the Concorde was from sea level.
So no, we haven't been "doing this for 60 years".
Hyperloop doesn't have to take the air from inside the tube into the cabin. It can just have air stored on board. Not particularly difficult...
Solar, wind and tidal power are all boondoggles which simply can't provide enough energy to satisfy worldwide demands and aren't reliable enough for distributed grids.
Schemes to put solar farms in the Sahara and pipe all that energy north ignore the burgeoning demands to the south, etc.
The mid-term answer is likely to be Molten Salt Nuclear Reactors - which aren't your grandfather's steam engines with red hot pokers in the boiler that the current water-based systems all are and don't have the safety issues that come with mixing flimsy metal rods holding radionucleides and ultra-hot, ultrapressurised, corrosive water. Steam explosions aren't nearly so scary if they don't come with a radioactive cleanup requirement.
You mentioned solar farms in the Sahara. Another big downside is all the turmoil in northern Africa. How are they going to be protected from attacks from groups like ISIS?
equalize the front and rear of the train; maybe we can halve the air resistance instead of completely eliminating it..
He is crazy if you think about it; I am not.