
Hyperloop Gets Test Track in California - benblodgett
http://news.yahoo.com/ultra-fast-hyperloop-train-gets-test-track-california-130857490.html
======
rmxt
A 5-mile test track won't be big enough to examine the biggest concerns:
thermal and seismic. The alpha brochure linked to in the OP barely touches on
the two. Here [1] is a better analysis/take-down of what thermal issues such a
long structure will encounter. (TL;DR: A 400-mile long continuous structure
will need to accommodate 1000 feet of thermal movement over it's length and
lifetime.) Seismic is another beast: it requires a much more thorough
examination than the cursory glance it was given in the alpha paper.

[1] [http://www.leancrew.com/all-
this/2013/08/hyperloop/](http://www.leancrew.com/all-this/2013/08/hyperloop/)

Thermal effects on Maglev research:
[https://www.lib.utexas.edu/etd/d/2007/kimh10315/kimh10315.pd...](https://www.lib.utexas.edu/etd/d/2007/kimh10315/kimh10315.pdf)

EDIT: Apologies for the negativity... I hope this reads as more of thoughtful
criticism, rather than as being hypercritical.

~~~
Retric
Thermal expansion is not really an issue that gets worse with distance, as the
track can simply be made from independent segments connected with expansion
joints. The issue is being able to cross from segment A to segment B not the
number of such segments. In other words if it works on a test track it scales
just fine, but getting that first connector to work is the hard part.

Earthquakes require active dampening which defiantly increases costs, but a
larger issue is how to cross fault lines as you need a very large turning
radius so very long segments of track need to be able to move. AKA you can't
do this:
[http://pubs.usgs.gov/fs/2003/fs014-03/pipeline.html](http://pubs.usgs.gov/fs/2003/fs014-03/pipeline.html)
Unless you’re willing to really slow down.

PS: Also of note, you are going to need safety exits on a fairly regular basis
and some way to quickly add air to the pipe as people are not going to be able
to walk hundreds of miles in case of an issue.

~~~
rmxt
Thermal _is_ an issue that gets worse with distance. Did you look at the
article that I posted above? If you are proposing expansion/slip joints at
every pier, that runs directly counter to the proposal which states that
expansion joints will only be needed near the stations. [1, pg. 27] If we go
according to the proposal, the slip joint at the stations on the test track
will only need to accommodate ~9 feet of movement (5280x5x6.5x10^-6x100)/2
compared to something an order of magnitude higher for a full-scale track.

Successfully designing for earthquakes does not necessarily mean active
damping. (That is, it is not "required" as you state.) Yes, many large
structures use specially designed mass or viscous dampers for dynamic loading
(Citigroup Building, NYC; Taipei 101; Millennium Bridge, London), but others
are designed to fail safely such that life and structure are preserved to the
greatest extent possible. Specifically for bridge structures, there is the
notion of plastic hinging in visible locations. [2] This way, the failures can
be identified and repaired before normal use resumes. Here are some relevant
state DOT guidelines. [3]

[1]
[http://www.spacex.com/sites/spacex/files/hyperloop_alpha-201...](http://www.spacex.com/sites/spacex/files/hyperloop_alpha-20130812.pdf)

[2]
[https://en.wikipedia.org/wiki/Plastic_hinge](https://en.wikipedia.org/wiki/Plastic_hinge)

[3]
[http://www.dot.ca.gov/hq/esc/techpubs/manual/bridgemanuals/b...](http://www.dot.ca.gov/hq/esc/techpubs/manual/bridgemanuals/bridge-
memo-to-designer/page/Section%2020/20-6m.pdf)

~~~
msandford
> Thermal is an issue that gets worse with distance.

I would respectfully disagree. The rail industry has figured out how to do
Continuous Welded Rail (CWR) quite well, using the elasticity of steel.

[http://blogs.agu.org/landslideblog/2011/03/08/distorted-
rail...](http://blogs.agu.org/landslideblog/2011/03/08/distorted-railway-
lines-in-the-christchurch-earthquake/)

Similarly the tube for the Hyperloop doesn't HAVE to free-float against its
foundations. It might be easier or harder depending on various factors to work
on expansion joints or doing the tube equivalent of CWR. You'd probably work
on both to figure out which is easier in the long run.

Considering that it's a 9-11ft diameter tube with about 1" wall thickness,
it's going to be pretty stiff, especially relative to traditional rails. The
moment of inertia means that it should be very resistance to bending or
buckling under compression and under tension steel is usually very good.

Given that there are going to be plenty of turns that the track has to make, I
would look at doing a combination of two things:

1\. Working towards a CWR style solution

2\. Allow some movement so that the corners can take up the slack as the tube
expands

The turns are very gradual and sweeping. But you could imagine that there's a
virtual intersection between two straight portions that you determine by
drawing lines from the straight portions until they meet. The actual turn will
take place far from here, but it's instructive. So as the tube expands, the
actual curve is going to move ever so slightly from the neutral position
towards the virtual intersection. So long as there is enough room on the
pylons to accommodate this, things will be pretty good. The tube will go from
being curved 0.1 degrees per 100 feet to 0.105 degrees per 100 feet (or
something like this) but this can be designed for and ensured that it doesn't
cause the tube to buckle or collapse. It's engineering, not the utter unknown.

~~~
HCIdivision17
That is one of the coolest articles on field engineering I've seen in a while.
Thanks a lot for sharing it - it really brings out how something like the
hyperloop can be tackled. So far, thermal effects have been my main point of
curiosity, but the idea of calibrating the steel to take care of it will
likely be the ... easiest? way around the problem.

At their desired vacuum pressures, the steel doesn't need to be anything
special, so I would love to see the mechanical engineering that goes into
designing the 5 mile track's materials.

~~~
msandford
The engineering to do a 5 mile section is pretty straightforward. It's only 5
miles long (25000 feet) and around 250 joints.

1\. Giant foundations and just handle the thermal stress by not letting
anything move

2\. Figure out the slip joints really well to soak up the ~125 feet of travel
and still hold a good vacuum

3\. Figure them out OK and just install extra vacuum pumps since there are
only ~250 joints

4\. Try out some/all of these options on 500 feet of tube in parallel to see
how it all performs and don't make a final decision on the whole 5 miles until
you have real cost numbers

The other thing I'll mention is that you don't need the steel to be continuous
in order to hold a vacuum. You need the inside face of the tube to be smooth
in order to not jerk around the vehicles, but all the sealing could be done on
the outside with clamp-on seals. If the average continuous tube piece is 100
feet long and the max thermal expansion is 0.5% then you only need a half-inch
gap between the tube pieces.

If your air bearings are say 3 feet long each and divided into 10 sections
internally which are fed through orifices so that no one section can rob all
the pressurized air flow then you're never going to lose more than 10% of your
bearing force and you should be able to glide right over these 1/2" gaps with
no problems. And if there are some problems a few accumulators (plain air
tanks or pressurized bladders) inline with the supply lines would probably
increase the momentary recharge capabilities enough to negate the problem.

700mph is 1000 feet per second or 12 inches per millisecond. That means a 1/2"
gap is crossed in just 40 microseconds or so.

------
Animats
They have a web site.[1] They claim to be hiring. They claim to have funding.
The web site looks like someone loaded up the generic cool new startup
template and stuck in some concept art in the indicated places. There's no
useful information about the technology or the business.

The big problem with this is not the technology. It's land acquisition. As
with high speed rail, you need a right of way that's straight or has very
large radius turns. There are sections of I-5 that are straight enough, but
high-speed travel between Bakersfield and Tracy isn't that useful. Tunnels can
help, but are not cheap.

China is building high speed rail through urban areas on pylons. As with most
elevated rail, the reality is much wider and more heavily built than the
concept art. (China's maglev is a one-off demo; China's high speed rail system
is huge.)

[1] [http://hyperlooptech.com/](http://hyperlooptech.com/)

~~~
Igglyboo
Their logo looks extremely similar to the Visual Studio 2010 logo.

[http://2.bp.blogspot.com/-1LB4PjiDdgU/Ur_tPvwj5HI/AAAAAAAAAo...](http://2.bp.blogspot.com/-1LB4PjiDdgU/Ur_tPvwj5HI/AAAAAAAAAo0/91HKtveyFok/s1600/VisualStudio2010.png)

~~~
swalsh
I think they need to change either the colors or the symbol... but having both
is throwing me off :D

------
ChuckMcM
Sigh

 _" The 5-mile test track is estimated to cost about $100 million, which
Hyperloop Transportation Technologies hopes to pay for with its initial public
offering (IPO) later this year, according to Navigant's blog."_

Run away, run far far away. They might as well do a kickstarter. Seriously,
what sort of "business" is a 5 mile test track?

Lets say you charged $25 for a "5 minute ride on the hyperloop!" and you got 8
people in it, and you had perfect efficiency, and you ran non-stop for 10 hrs
a day, 7 days a week then $100M is 414 days. And that isn't including the cost
of running the ride in the first place. I guess I'll find out why they think I
should think about investing in their S-1 but for right now, I am totally not
seeing it.

~~~
stephengillie
This reminds me of the Seattle Monorail, which continues to operate today. For
a few dollars, you can ride swiftly and smoothly from one part of Downtown
Seattle to another part of Downtown Seattle.

Some day, scientists hope, the value of the monorail will be seen. That day,
we expect to extend the rail line to other communities. Meanwhile, we just
pulled a tunneling machine out of its boring hole, continue to expand the Link
Light Rail system, and are developing various trolley-based solutions such as
the ones in South Lake Union and First Hill.

~~~
Shivetya
oh, that 600 million dollar per mile tunnel?

not a great use of transportation dollars, think of how many EV buses they
could buy, which on the whole buses tend to go where people want and do it
more often than light rail which not only costs a fortune to build but
maintain as well

~~~
goodcanadian
I won't defend that project specifically because I know nothing about it, but
I would like to offer a couple of comments:

As a passenger, I have always found the experience of riding rail to be far
superior to riding a bus for a lot of reasons including but not limited to
speed and comfort.

A train generally has much higher capacity than buses, and if well utilised, a
lower operating cost per passenger. An ideal transport system will use trains
for the high traffic trunk routes and a tightly integrated bus system as
feeders for the train line. It should never be expressed as an either/or
proposition. Both are necessary.

~~~
stephengillie
When traveling from Seattle to LA, Greyhound buses are better than Amtrak
trains for several reasons: faster, cheaper, easier to book, and less risk of
Civil Asset Forfeiture.

~~~
goodcanadian
Amtrak does not qualify as a proper rail system . . . besides, the comment was
clearly referring to municipal transit. For Seattle to LA, I can't imagine any
rail system ever beating flying.

------
sixQuarks
When the US government literally loses track of $100 million in cash, no one
blinks an eye. When a guy who has built an electric car company AND a space
rocket company proposes a revolutionary transportation alternative and has
people excited enough to spend $100 million on it, people go nuts. I can't
believe how small-minded some people are.

~~~
the_falcon
From the article "Separately, Musk has said he plans to build his own 5-mile
test track, likely in Texas, for companies and students to test out potential
Hyperloop designs."

------
huuu

      * Invent something totaly new
      * Test it on a small scale
      * Get a lot of negative comments on HN
    

Com'on people. This might be the transportation of the future!

~~~
Someone1234
As opposed to Elon Musk being a sacred cow who we cannot criticise at all
without being attacked/downmodded?

The Hyperloop, to put it generously, has a lot of "unanswered questions" and
practical limitations. Just considering the safety (and escape) of this thing
takes you into areas that raise legitimate concern.

I'm not going to discount it completely with aircraft still around and failing
as badly as they fail, it might be workable, I just want to see some figures
on how much it will cost Vs. Maglev (a technology already deemed too expensive
to deploy on the medium to large scale), and more so how much it will cost to
make it safe.

Would I love to go across the continental US in a few hours? Heck yeah. Will I
be able to afford it if it has Concord's ticket price? Likely not, I'll fly.

~~~
brenschluss
> The Hyperloop, to put it generously, has a lot of "unanswered questions" and
> practical limitations.

It's a chicken-and-egg problem. New things are uncertain, uncertain things are
risky, risky things aren't funded, thus new things stay new.

"This new technology is expensive because it's new!" is a tautology that gets
us nowhere in terms of progress at a social level.

------
geon
> The problem with traveling in an evacuated tube is, if you lose the vacuum
> in the tube, everybody in the tube will crash

Wouldn't that be a "crash" into a gradually rising air preassure? Something
like a smooth deacceleration.

~~~
VLM
I wouldn't worry about an air valve being left open quite as much as the
vacuum being broken because a big chunk of concrete (or whatever) is now
sucked into the tube in the path of the train.

Perhaps in the very unlikely event it ever rains again in California, water in
the tube could be an issue, or lightning damage. That brings up the logical
question of how many customers you'll have if none of them have any water to
drink. Perhaps this would make more sense as a project under the Chicago
Regional Transit Authority, or parallel to the existing Acela track on the
coast.

~~~
danielweber
> because a big chunk of concrete (or whatever) is now sucked into the tube in
> the path of the train

1 atmosphere of pressure isn't going to suck in anything concrete, except
maybe in dust format.

------
aetherson
The biggest problem with this headline is that it suggests that the hyperloop
is "getting" a test track. When the actual situation appears to be that the
hyperloop is getting a plan for a test track that is heavily contingent on
highly speculative funding.

If it actually had a test track, then most of the discussion in these comments
could be obviated.

~~~
the_falcon
Exactly, this was a PR Release for a hyperloop cash grab in hopes they IPO

------
Osmium
Regardless of what you think of this specific project, I'm encouraged that
people are still 'Thinking Big'. Making the future happen is up to us!

------
coderjames
I'm clearly missing something important because otherwise somebody would have
built this already, but instead of using the fans for levitation as proposed,
why not keep using the magnets?

I'm imagining a tube with (8?) magnets equally-spaced around the perimeter so
that the carriage inside automatically stays centered in the tube. We already
know how to toggle the magnets to produce forward motion (see maglev trains).
Could still use the partial-vacuum to keep drag down. And you remove the
single-point failure mechanisms of the fans on the carriage and minor
misalignment of tube segments.

~~~
throwaway41597
I think it's because you'd need a continuous line of magnets over the full
tube, as opposed to accelerators at intervals so it's probably orders of
magnitudes cheaper. I don't know about the reliability of compressors but I'd
say you could have a couple onboard if they're an issue.

------
hyperbovine
"If the position of the wall deviates from straightness by a few thousandths
of an inch, you could crash ... if you lose the vacuum in the tube, everybody
in the tube will crash ... the vehicle's compressor ... can't fail, or the
pods will crash ... The 5-mile test track is estimated to cost about $100
million, which Hyperloop Transportation Technologies hopes to pay for with its
initial public offering (IPO) later this year."

This article will one day be featured in a museum exhibit on laughably
divorced-from-reality bubblethink.

~~~
jcfrei
Exactly. How can you do an IPO without any earnings? NYSE requires at least
$10 mil over 3 years before they even list a company - I'm assuming other
exchanges are similar. And if they don't list it on a major exchange, I doubt
they can raise that amount of money...

~~~
mortehu
There's an exchange called NASDAQ that have different sets of financial
requirements you can satisfy to get listed. Some of them don't require any
earnings at all, e.g. Nasdaq Global Select Market, Standard 4.

[https://listingcenter.nasdaq.com/assets/initialguide.pdf](https://listingcenter.nasdaq.com/assets/initialguide.pdf)

------
saosebastiao
This is hard for me to do because 1) I probably respect Musk more than any
living engineer, 2) I can't stand the CHSRA and their incompetence, and 3) I'm
arguing from my comparatively unsuccessful keyboard against someone who is in
every way my superior when it comes to engineering and business, and I know
I'm gonna be the one to look like a fool here. But I'm going to do it anyway
and try as best as I can to avoid the middlebrow dismissal.

Hyperloop is a nerd dream and it doesn't have a chance at _financial_ success.
The fundamental problem has nothing to do with the technology, which appears
amazing _and_ viable. If anyone can overcome the few nagging engineering
issues, Musk and Co are the ones to do it. No, it has to do with not having a
viable market plan, suffering from very common delusional assumptions in
business models that have fucked over railroad capitalists for well over 2
centuries now, including three major railroad bubbles (Railway Mania as well
as the Panics of 1893 and 1873). [1]

The faulty assumption is that the viability of the railroad hinges on the
ability to go from major city to major city as fast as possible. This is only
partially true. Of course you want to be as fast as possible, but the worst
possible way to be as fast as possible is to eliminate stops in smaller cities
and towns, which is exactly what Hyperloop is planning on doing. Those small
towns usually end up being the most prominent drivers of revenue,
overshadowing the large-city-to-large-city revenue by an order of magnitude.
Even the CHSRA business plan shows that their revenue model does not depend
heavily on the SF<->LA passenger volume.

You can typically think of demand for travel in terms of cultural
dependencies. I have a need for employment, therefore I travel to work. I have
a need to visit family, therefore I travel to family. I have a need for tuna,
therefore I travel to the wharf market. I have a need for a visa, therefore I
travel to the embassy. These cultural dependencies result in a demand
distribution for travel that roughly fits a power law profile. The demand for
near travel (x > 0) is exponentially greater than further travel (y > x). It
is not hard to speculate that the passenger miles travelled by Angelenos
traveling to work outweighs the aggregate passenger miles travelled between
Los Angeles to San Francisco on any given day...LA County's Metropolitan
Transit Authority alone accounts for 5.4M passenger miles a day [2],
approximately equivalent to 14,000 passengers traveling between SF and LA.
More importantly, the larger the city, the more your cultural needs are met by
your own city. If you live in Los Angeles, your probabilistic need to travel
to San Francisco is _much_ lower than someone from Fresno, because your needs
are mostly met by Los Angeles. When I lived in Stockton, I travelled to
Oakland or San Francisco almost on a weekly basis...but now that I live in
Seattle, I travel outside of the Puget Sound region maybe 2-3 times per year.

In the very beginning, this faulty assumption was actually a _safer_
assumption to make than it is today, due to the lack of airlines and
automobiles. The railroad literally was the fastest way to get from city to
city, with no exceptions. But now it isn't. Once you go over about 300 miles,
a well timed trip by plane is often as fast or faster (a lot of people will
say that 500 miles is the threshold of competitiveness, but travel market
share peaks and then drops off after about 300 miles). Under 100 miles, the
freedom of a car to leave without a schedule often makes cars faster. Any time
you have competition, you lower your market share, with your comparative
competitiveness determining how much market share you lose.

So this is how it has played out hundreds if not thousands of times in the
history of railroads: 1) Some big city businessman sees a slow trip to a city
that he commonly has to travel to. He sees a demand for faster transportation.
He throws together a business plan that makes the correct assumption that City
A has X people, City B has Y people, and a fast connection between them will
yield Z% market share of the travel D demand between them. He figures that in
order to get that fast travel time, he can only stop at the largest cities in
between...or possibly no stops at all! He then looks up a similar city or
railroad (lets say B & S railroad), looks at ridership figures, and tries to
back into D, and then inflates the Z figure to reflect the fact that his
railroad will be faster because there are fewer stops. Therefore his revenue
model becomes X * 0.5D * Z * P + Y * 0.5D * Z * P (where P == ticket price) 2)
He sells some stocks and bonds (or in the case of modern capitalism, lobbies
for grants), and builds a railroad. From this article, it looks like this step
is starting. 3) After a few months, he realizes his model is inaccurate. At
this point, he will do one of two things: either advertise more or remove
stops to make it faster, both of which exacerbate the cash flow problem. 4)
After about a year, he is bankrupt. The bondholders reclaim as much as they
can by selling the railroad to some other capitalist who will with high
assurance do exactly the same thing, but with a greater chance of success due
to a much lower investment. And thus plays out the railroad consolidation
game.

In terms of the model, his failure was actually three failures multiplied
together. 1) He assumed that the ridership of B & S railroad was primarily
between termini. This meant his D figure was too low because he vastly
underestimated the demand to and from the small intermediate cities. 2) He
assumed that B & S ridership figures were rides at full terminus-to-terminus
prices, therefore inflating P. 3) He assumed that D was a linear function of
population, ignoring that the larger the city the lower the cultural need for
travel, thereby inflating D. The only thing he got right was X and Y.

The practical implication of this is that if you want a successful, profit-
maximizing railroad, you need to optimize the need for speed with the need to
pick up passengers along the way. If you are a capitalist that cares about
maximizing profit, this unfortunately means having a railroad that looks like
a slow kludge, because it means making unglamourous stops in unglamourous
towns. And it also means that technophile idealism puts you at a competitive
disadvantage.

[1] for more information/history, this is a great writeup, with a couple
chapters that clearly describe this delusion. It is very long, but amazingly
interesting and worth reading outside of this reference for anyone interested
in technocapitalism or bubble economics.
[http://www.dtc.umn.edu/~odlyzko/doc/hallucinations.pdf](http://www.dtc.umn.edu/~odlyzko/doc/hallucinations.pdf))

[2]
[http://www.apta.com/resources/statistics/Documents/FactBook/...](http://www.apta.com/resources/statistics/Documents/FactBook/2013-APTA-
Fact-Book.pdf)

~~~
aetherson
If the hyperloop delivers on the promise of being substantially faster than
air travel for its route, then presumably that makes a terminals-only approach
more viable than it would be for HSR. (Which isn't to fully argue against your
post).

~~~
saosebastiao
That is true. A terminals-only Hyperloop would definitely capture more of the
market share than a terminals-only HSR.

I'm assuming you already acknowledge this, but successful marketing involves
positioning to avoid competition and attempt monopoly on the market segment
(It seems Thiel is the latest to rebrand this concept). Low-cost stops at
minor intermediate cities is a competitive advantage that no airline would
ever be able to compete with, as the costs of takeoff and landing are huge
relative to the cost of the trip.

Major city termini > 300mi apart, however, is a huge competitive advantage for
airlines. No matter how fast you get, you are always going to give up some
market share to airlines on more marginal considerations like schedule
flexibility, seat size/comfort, baggage limitations, etc. That is a huge and
potentially very expensive rabbit hole for competition that a city-to-small-
town transportation system can mostly ignore.

------
joelrunyon
Why would they build this in California? Why not pick a place in pretty much
ANY other place in the US that has demonstrably cheaper land.

~~~
devindotcom
I was thinking it makes sense in that California, sort of following I-5, is
where the Hyperloop would supposedly go... but no. There's no reason to
construct a proof of concept track there. Go buy some flats in the middle of
nowhere and get a working prototype going first.

~~~
Gibbon1
Makes sense if you're Musk and want to jot down to Santa Monica to see your
mistress Friday evening. (Come on seriously this is what this is all about,
you know it, I know it) Not so good if you want to commute to your worker bee
cubical job Monday morning.

------
skizm
Isn't hyperloop not supposed to be efficient unless it runs over 1000 miles or
something like that? It has to basically ride in the valley of a soundwave and
to get up to speed and back to rest takes the majority of the time and a good
amount of runway.

------
joshdance
In the article they quote someone as saying if you lose the vacuum everyone
crashes? That seems to be exactly opposite what I read in other articles. Is
that true?

------
trhway
if we're going to build a 5 mile evacuated pipe while not try to use it as a
prototype of a space launch? At modest 50G acceleration the exit speed would
be 2.5km/s - not a production, but it would be a good test prototype to get
real funding for the real deal to the top of Kilimanjaro.

~~~
pas
Because you'd still hit dense air at the top with 2.5km/s. You would need to
go a about as high as the blackbird could fly to exit the tube with some sort
of grace. (Or maybe even higher.)

[http://upload.wikimedia.org/wikipedia/commons/thumb/9/9d/Com...](http://upload.wikimedia.org/wikipedia/commons/thumb/9/9d/Comparison_US_standard_atmosphere_1962.svg/2000px-
Comparison_US_standard_atmosphere_1962.svg.png)

------
wehadfun
The article makes it sound like a flea could come in there and kill everyone.

------
the_falcon
The wording of this article is interesting. I personally know the people
behind this project. This is from a PR firm, and kickstarter knockoff who
'lost' a lot of my friends startups money

This company (Hyperloop Transportation Technologies) got no funding, Hyperloop
Technologies did ($8.5m).(which is in reality a PR firm called jumpstarter pr
in El Segundo)

They are hoping to raise the funding at IPO

"Now, the company Hyperloop Transportation Technologies Inc. (which is not
affiliated with Musk or Tesla) has inked a deal with landowners in central
California to build the world's first Hyperloop test track"

"The 5-mile test track is estimated to cost about $100 million, which
Hyperloop Transportation Technologies hopes to pay for with its initial public
offering (IPO) later this year, according to Navigant's blog."

Musk is building his own Separately, Musk has said he plans to build his own
5-mile test track, likely in Texas, for companies and students to test out
potential Hyperloop designs.

