[Caveat: I've been getting up to speed on the Hyperloop and reaching out to knowledgeable people in the field, but I'm no expert and though I'm trying to be careful, some of the technical details may need to be revised later. On a related note, if you do see something wrong (or even not quite right), please let me know.]
From the Verge [emphasis added]:
Hyperloop Transportation Technologies (HTT) announced today that it will be using a new type of sensor-embedded carbon fiber to make its capsules, capable of transporting passengers through a nearly airless tube at speeds up to 760 mph, safer than ever. The company is calling this new material "Vibranium," which may sound familiar to anyone with a passing knowledge of Marvel Comics and its wildly popular Cinematic Universe.We should probably come back to this as an example of how these hype spirals mix comically over-the-top language with outlandish claims that are supposed to be taken seriously (Vibranium is explicitly meant as a joke. With the numerous Elon Musk equals Tony Stark comparisons, the call is quite a bit more difficult). Instead of the hyperbole, for now though, I want to focus on the vagueness of the language and the way it interacts with journalists' weak grasp of the topic.
In the comics, Captain America's iconic shield is made of a nearly indestructible metal called Vibranium. It is almost exclusively found in the tiny (and fictional) African nation of Wakanda, the ancestral home of the Black Panther, who had his silver screen debut this month in Captain American: Civil War — and will be starring in his own standalone movie in 2018. Or around the same time the first Hyperloop is expected to be in operation.
HTT's Vibranium, though, won't be used to make any superhero flair, but rather a dual-layer coating for the company's Hyperloop pod that will provide the passengers with twice the protection should anything damage the exterior. The company boasts that its Vibranium is "eight times stronger than aluminum and 10 times stronger than steel alternatives," which is fairly standard for reinforced carbon fiber. What makes HTT's version special is the embedded sensors that can transmit "critical information regarding temperature, stability, integrity and more, wirelessly and instantly." HTT unveiled a section of its Hyperloop capsule made of Vibranium at the Pioneer's Festival in Vienna today.
Musk never provided a really good answer to why the Hyperloop would cost so much less than comparable existing structures did but he could make the case that the hyperlink might cost less to implement that other proposed vactrains.
Before we go there, however, it is important to step back and realize just how little distinguishes the Hyperloop from the hundreds of similar proposals that have been made over the past century. This is very much the stuff of a mechanical engineering major's senior project. There is a very real possibility that every major aspect of the plan has been arrived at independently before over the years but without the necessary PR push to get it noticed.
That said, the idea of having the pods use some of the small amount of air in the near vacuum to generate their own air cushions rather than relying on mechanisms in the track is quite clever. Though questions remain as to whether this can be made to work reliably on a large scale over number of years, it does potentially offer a substantial cost advantage over many of the other designs for similar super high-speed trains. As I understand it (see caveat above), this design greatly simplifies the construction of the track (keeping in mind that simple is a relative term when you're talking about a structure that maintains a near vacuum over hundreds of miles and reliable handles passenger carrying pods traveling in excess of 700 mph).
Which brings us to this:
Hyperloop Transportation Technologies, one of two LA-based startups working to build Elon Musk’s futuristic transportation system, announced today that it has licensed a technology called "passive magnetic levitation" to power its prototype. The system is "a cheaper, safer alternative" to regular magnetic levitation, or maglev, which is currently in operation powering high-speed trains in China and Europe.For the record, Post's ideas are very cool. They might even be significantly cheaper than a standard maglev, but the system would almost certainly be more expensive than the pod-generated air cushion system Musk proposed.
Passive magnetic levitation, which was developed by the late physicist Richard Post in 2000, uses unpowered loops of wire in the track and permanent magnets in the train pod to create levitation. By contrast, maglev requires complex and expensive infrastructure upgrades, such as power sources placed at intervals along the track. Post, who worked for the Lawrence Livermore National Laboratory in Livermore, California, until his death in 2015, called his new system "the Inductrack."
To sum up:
1. HTT is not actually a Hyperloop but rather a maglev train;
2. The overwhelming consensus among independent experts is that the Hyperloop would cost at least 10 to 20 times as much as Musk claims;
3. The HTT maglev will almost certainly cost more than the Hyperloop.
There was a Scientific America article on vacuum trains in the 1960s, details vague after all this time, naturally.
ReplyDeleteI saw a Popular Science article on vactrains that I believe was from the late 20s. It would be interesting to see how much (or how little) had changed.
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