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201 MPH Pod Run Wins SpaceX's Second Hyperloop Competition (geekwire.com)
An anonymous reader quotes GeekWire:
The speediest team from SpaceX founder Elon Musk's first Hyperloop pod competition has done it again: WARR Hyperloop from Germany's Technical University of Munich won today's second contest by sending its magnetic-levitation pod through a nearly mile-long test tunnel at a peak speed of 201 mph [video]. Musk announced WARR's victory to a crowd in the stands at SpaceX's headquarters in Hawthorne, California, and in a tweet... This weekend's competition brought about two dozen teams to Hawthorne, including a student group from the University of Washington. Each of the teams developed a pod that was designed to test engineering approaches for Musk's Hyperloop rapid-transit concept, which calls for sending people and cargo through low-pressure tubes at near-supersonic speeds.
Musk also tweeted that it "might be possible to go supersonic" in the 0.8-mile test Hyperloop tube, though he conceded it would require an extremely high acceleration (and deceleration) because of the short distance.
"For passenger transport, this can be spread over 20+ miles, so no spilt drinks."
Musk also tweeted that it "might be possible to go supersonic" in the 0.8-mile test Hyperloop tube, though he conceded it would require an extremely high acceleration (and deceleration) because of the short distance.
"For passenger transport, this can be spread over 20+ miles, so no spilt drinks."
When 267mph maglev is already in service in other countries?
Shanghai's maglev does the 430 km/h just for show, 2h30 per day and it loses money continuously. It was made as a political statement. Even if Hyperloop only did 320 km/h, but did so at a low cost (and profitably), you'd have something the the Shanghai maglev doesn't have. I'm not saying it does, but you're comparing apples to oranges.
Maglev in evacuated tubes can, in theory, be one of the most energy efficient ways of transportation. There is no loss to friction–so not much to fear from Thermodynamic's second law, making the process reversable in theory. And if you can then use the Maglev technology to recover most of the kinetic energy, you're there.
It really puzzles me that a website geared towards engineers, scientists and other nerds from across the world would use imperial units in such a news article.
This was a bunch of students doing this for a project, and it reached that speed on a 1.7 km test track. With a longer track and more budget, they expect to go supersonic eventually. This is nowhere near a finished product, so don't compare it to one.
Why is everyone so pessimistic about everything Musk does? Even here on a supposed nerd site? Jeez, I know the guy uses a lot of hyperbole and has impossible ideas like, say, landing rockets on barges (o, wait, that actually worked) or making usable electric family cars that outperform two seat supercar monsters (o wait, he did that too). Maybe just see where this idea goes? We need more people like him, billionaires that are not afraid to push boundaries and try new things that may well fail but might just make a huge difference in the world, instead of just buying big yachts. I know he's crazy. That's what makes all the difference in this world of paralysing risk averseness.
When 267mph maglev is already in service in other countries?
Let's face it, there is no innovation in Hyperloop. It's just vaporware.
Elon didn't invent maglev technology, the electric car, or the solar panel. Apple didn't invent the portable music player either. These companies are known for innovating by taking designs to the next level. When it comes to high-speed transit, the innovative part would be delivering a product before the generation who needs to use it dies, and perhaps deliver a profitable design.
Can that maglev do 0-267-0 in 0.8 miles?
No. It was design to carry human passengers without killing them.
Claus
And how fast did the very first maglev prototype go? I bet it wasn't 430km/h.
No sig today...
The real technical challenge is not how to build a pod that can accelerate to supersonic speed inside the near-vacuum, the real challenge is how to build a very long vacuum tube that would be safe and cost-efficient to operate. So all those hyperloop competitions do nothing to advance the hyperloop idea -- it is just a show for a gullible public.
Which is why the Hyperloop Alpha proposal was A) for a mild vacuum, not a hard vacuum, and B) did not use maglev. Specifically to address both of those issues.
This student competition is something entirely different. And each of the different companies which have taken on the "hyperloop" name are choosing their own technologies. But as for Hyperloop Alpha (the original proposal), it was very much about majorly reducing the cost of high-speed ground transport.
He's just being nice so my real father won't freeze him in carbonite and sell him for spice.
1) Requirements for straightness on HSR and Hyperloop are the same, for a given speed. And there are standard solutions which very much work well for thermal expansion and are widely used in industry - either floating the object that would expand and allowing its expansion in a controlled manner, expansion joints, or resisting the expansion. Hyperloop Alpha proposed to use the first one, although any of the three could work. High speed rail generally uses the latter - pretensioned rail and heavy sleepers.
2) Building vacuum lines is no more complicated than building pressure lines, contrary what biochemists-pretending-to-be-engineers on Youtube would have you believe. There are standard guidelines and formulae for them, and no, a properly designed vacuum line does not suffer cascading failures.
He's just being nice so my real father won't freeze him in carbonite and sell him for spice.
Exactly right, the negative attitude has always surprised me in respect to Musk, who at least is pushing the boudaries of technology.
On a tech nerd site, its rather ironic. If we had listened to all the negative Nellys in the past, we would still be arguing over what colour the wheel should be. To the B ark with them.
At 1g acceleration, it takes around 11 seconds to travel half the distance in this tube (assuming that the other half is spent decelerating). That's a peak speed of 110m/s, or around 245 miles per hour, so this train had less horizontal acceleration than humans experience vertically just by being on this planet. Give them a comfy chair and they'll happily manage that level of acceleration for 30 seconds to a minute. And you can always trade a little bit time for comfort. Half the acceleration and accelerate for two minutes instead of one and you'll add two minutes (one at each end) to the total travel time, which won't make much difference in a half-hour journey.
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Can that maglev do 0-267-0 in 0.8 miles?
No. It was design to carry human passengers without killing them.
Hmm, is there an error in my maths then?
ignoring trivial rounding that is...
267 mph = 430 kph = 120 m/s
0.8 miles = 1.3 km
Assuming a constant acceleration, from rest, to peak speed, followed by constant deceleration, to standstill, pod will use half the track to reach peak speed.
i.e. distance to reach peak speed = 0.65 km = 650 m.
Using: v^2 = u^2 +2as gives:
'v' and 'u' are interchangeable, depending on whether we're accelerating or decelerating. 'a' will have the same magnitude in both cases...
120*120 = 0 + 2*a*650
=> a = 120*120/(2*650)
=> a = 11 m/s^2
Are you really trying to tell us that a human body can't accelerate at 11 m/s^2?
For reference acceleration due to gravity is roughly 9.8 m/s^2
Unless there's an error in my maths of course - it has been 30+ years since I studied these equations in school...
The math is correct, but gravity doesn't go away, so total acceleration with horizontal track is sqrt(11^2+9.8^2) m/s^2=14.7 m/s^2 = 1.5g. Not deadly. Still, killing jokes is no laughing matter.
Why is everyone so pessimistic about everything Musk does? Even here on a supposed nerd site? Jeez,
It's not just Musk, it's anything outside the comfort zone or cutting edge technology. Slashdot is very different than it was when it was new. I think the average age of user on here is much older than it used to be.
We have old jaded engineers, IT staff, etc, as the majority of visitors now. Anything that wasn't possible to do with tech when they were in school must therefore always be impossible. Because one or two technologies didn't take off as quickly as expected... no technology will.
This is a much more pessimistic place than it was 10+ years ago.
"That's the way to do it" - Punch
Slashdot isn't going to change
Given what we have witnessed on this site in the past 10 years, how can you honestly say that with a straight face?
Perhaps he should say "this aspect of Slashdot isn't going to change". It's an American site, and a primarily American readership. Always has been, and there is no indication that's likely to change. And for better or for worse (mostly worse), Americans use the Imperial system, except when we don't even follow that, e.g. US vs Imperial gallon.
[The history of the gallon difference is kind of interesting. The UK had several definitions of "gallon" including the wine gallon (231 in^3, standardized in 1706), the ale gallon (282 in^3, standardized in 1700), the Winchester gallon (272 in^3, standardized in 1697) and the Irish gallon (217 in^3, standardized in 1495). The US standardized on the wine gallon, and that remains the US gallon today. In 1824 the British established a new Imperial gallon which didn't match any of their previous gallons. It was defined as the volume of 10 pounds of water at 62F.
While I'm being pedantic, it's also worth noting that the US gallon wasn't originally well-defined, because the inch wasn't well-defined. The inch was vaguely-defined per the old British definition as the length of three barleycorns, though as of 1814 the canonical inch was a measure stored in the Exchequer chamber in the UK. In 1866, the US inch was defined as 1/39.37th of a meter, which gave it, and therefore the US gallon, a precise measure. In 1959 it was redefined as 1/36th of a yard, which was in turn defined as 0.9144 meters, making the inch exactly 2.54 cm long, and decreasing its length by two millionths, thereby shrinking the gallon by ~6 millionths.
Actually, you can argue that the length of the inch, and hence the gallon, was changed -- or at least clarified -- three more times, when the definition of the meter changed. In 1889 the International Bureau of Weights and Measures replaced the prototype bar in France and created calibrated copies which were distributed around the world. The US received #27, which was calibrated at 0.9999984m ± 0.2 m. That was used to establish the size of the US inch. In 1960 the meter was redefined as 1,650,763.73 wavelengths of the orange line of krypton-86. Then in 1983 the length of the meter was redefined as the distance traveled by light in vacuum in 1/299,792,458 of a second.
This, of course, means that lengths are now defined in terms of time measurements, which raises the question of the definition of a second. The second was defined in 1967 as the duration of 9,192,631,770 cycles of a cesium-133 atomic clock. In 1980 this was further clarified to be a clock at mean sea level, and in 1997 clarified again to specify that the cesium atom should be at rest at 0K (which none are, but corrections to measurements of real atoms can be applied). Future refinements in the definition of a second are all but inevitable, especially since the definition of mean sea level is problematic in various ways.
The US survey inch, by the way, is still defined as 1/39.37th of a meter. So a survey mile is about 1/8th of an inch longer than a regular mile. Over long distances, the difference matters.
And, yes, this post is the result of an hour-long tumble into a wiki-hole which started with a desire to find the history of the difference between US and UK gallons.]
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