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Hyperloop Alpha [pdf]

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Re: Hyperloop Alpha [pdf]

#41

Post by jessaustin »

hop wrote: post #16

I wonder what they have in mind for how stations will offload/onload capsules onto the loop. That will be heck of an engineering problem to solve - ultra high safety, pressurized environment, fast turnaround times... My initial thought was they would have switches on the track like a normal train and capsules would veer off. But I bet they would come to a stop on there own and then get lifted vertically off the train…

This is addressed in the document. Essentially, each station is a terminus, so airlocks are transited at low speed. A turntable reorients trains for their next trip. The only switching required takes place entirely within the evacuated zone. (This is for when spurs are built to serve e.g. San Diego or Las Vegas.)

Re: Hyperloop Alpha [pdf]

#46

Post by mpyne »

orofino wrote: post #29
kailuowang wrote: post #23

Earlier quoted context omitted.

On a bus you have the chance to get off every 5-10 minutes, that's a big difference. There will be thousands of passengers on that day. Just imagine if you have to do this trip 10 times a day every day for 100 days, will you still take risk? Update (since I've been downvoted): All these buses analogy isn't exactly the same case because they still have the option to stop somewhere, which give the passengers the assura…

You're thinking city buses. I'm thinking long-haul busses (like greyhound in the US). Greyhound buses likely have facilities, what I'm actually talking about are the buses used a core parts of the transportation infrastructure all over South America. Many of these also have facilities but I've been on many where the bathroom isn't functioning or just plain isn't there. You can easily travel for 30 minutes to an hour…

Interestingly, my DC Metrorail trip to home or work takes between 45-60 minutes one-way... and there are no facilities on the train itself, and very few stations have any public-accessible facilities. "Holding it" has honestly never been an issue, you either go before you leave, or sack up and wait until you get home. Worst case is probably that you get sick en route and well... that alone wouldn't wreck Hyperloop.

Re: Hyperloop Alpha [pdf]

#47

Post by mpyne »

tlb wrote: post #39

He doesn't properly address thermal expansion of the entire system. A long straight steel tube from SF to LA will expand a total of 300 meters over a 40C temperature change. Where does it go?

If I read it right, the movement is absorbed by shock absorbers that need to be installed for earthquake protection anyways. You just need to make sure that the segment between the lateral movement/shock absorbers are sized such that the differential thermal expansion doesn't violate the deflection requirements.

Re: Hyperloop Alpha [pdf]

#49

Post by mpyne »

jessaustin wrote: post #43
bbrooks wrote: post #19

What's the ideal format for an open source whitepaper? Certainly not PDF. Straight up HTML on Github?

What disadvantages do you perceive for PDF?

The same ones that we perceive for "open source development" on compiled binaries.

With that said, it's not hard in this case to C&P to something more suitable for GitHub and really get things kicked off, but LaTeX would be more suitable.

Re: Hyperloop Alpha [pdf]

#50

Post by nickpinkston »

rwmj wrote: post #25

It's interesting that the Shinkansen has raised sections built on pylons, especially the new bits they built in the last few years in the built-up areas in the north of Japan.

As does the Chinese system and for the same reasons Musk addresses.
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