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Hyperloop Alpha [pdf]

spacex.com

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Re: Hyperloop Alpha [pdf]

#81

Post by hackula1 »

orofino wrote: post #17

The focus from people on bathrooms is puzzling to me. I've been on buses, without facilities, that go for hours without stopping. This is a 35 minute ride with restricted movement, if you greatly fear being able to hold it for that long, there are other, less efficient methods of transport to accommodate you.

I would point people towards the Stadium Pal, described by David Sedaris. Essentially, it is a urine bag strapped to your leg attached to an external catheter. I am not sure if it works for women, but I am sure Musk could figure that out.

Re: Hyperloop Alpha [pdf]

#82

Post by erikpukinskis »

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?

I don't know how to do the math, but couldn't it be absorbed by the horizontal play at each plyon? Imagine the tube "zig-zagging" a tiny bit at each column.

Re: Hyperloop Alpha [pdf]

#83

Post by orofino »

hackula1 wrote: post #81
orofino wrote: post #17

The focus from people on bathrooms is puzzling to me. I've been on buses, without facilities, that go for hours without stopping. This is a 35 minute ride with restricted movement, if you greatly fear being able to hold it for that long, there are other, less efficient methods of transport to accommodate you.

I would point people towards the Stadium Pal, described by David Sedaris. Essentially, it is a urine bag strapped to your leg attached to an external catheter. I am not sure if it works for women, but I am sure Musk could figure that out.

Similar, though less invasive, solutions exist for 'emergencies' on private planes and such. They come with support for both male and female genitalia.

Re: Hyperloop Alpha [pdf]

#84

Post by TomGullen »

toomuchtodo wrote: post #68
alex-g wrote: post #11

It's interesting that the biggest line item in the costing is not the tube, nor the capsules, nor the vacuum pumps, nor the solar panels, nor the land, but the concrete pylons that support the tube - about two-fifths of the total. The pylons are planned to be 30m apart, making for about 25000 of them.

But that's the beauty of it! You can make those pylons anywhere, truck them in, and install them in whatever order you want. It's construction....that scales up almost effortlessly.

Also much easier to maintain and replace

Re: Hyperloop Alpha [pdf]

#85

Post by erikpukinskis »

nsxwolf wrote: post #30

It's too bad the tubes and trains can't be made transparent. Imagine the view!

They should fly a helicopter down the California coast with a 4k camera pointed out towards the ocean and then mount 30" LCD screens next to each seat and play back the video at high speed, with image stabilization, correlated with the position of the train.

Re: Hyperloop Alpha [pdf]

#86

Post by tlb »

erikpukinskis wrote: post #82
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?

I don't know how to do the math, but couldn't it be absorbed by the horizontal play at each plyon? Imagine the tube "zig-zagging" a tiny bit at each column.

To absorb the 15mm expansion over each 30M long tube, you'd need to zig-zag nearly a meter. At full speed you're passing through 10 tubes per second. It would literally shake your head off.

Re: Hyperloop Alpha [pdf]

#87

Post by thrill »

erikpukinskis wrote: post #85
nsxwolf wrote: post #30

It's too bad the tubes and trains can't be made transparent. Imagine the view!

They should fly a helicopter down the California coast with a 4k camera pointed out towards the ocean and then mount 30" LCD screens next to each seat and play back the video at high speed, with image stabilization, correlated with the position of the train.

Each passenger gets an Oculus Rift headset and can choose their virtual route.

Re: Hyperloop Alpha [pdf]

#90

Post by Someone »

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?

"By building a system on pylons, _where_the_tube_is_not_rigidly_fixed_at_any_point" [...] "A telescoping tube, similar to the boxy ones used to access airplanes at airports would be needed at the end stations to address the cumulative length change of the tube"

So, the tube is lying loose on the pylons, and he assumes it will keep its shape while expanding.

I think that is highly optimistic for a tube that is a straight line, even more so for one that is curved.

If he manages to accomplish that, the end stations will move over 300 meters, in total. Hopefully, when the tube contracts again, the motion will be reversed perfectly. Otherwise, that end station in LA could slowly move north or south over the years.

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