The Race To Create a Hyperloop Heats Up (wsj.com)

An anonymous reader writes: When Elon Musk unveiled his idea for the "Hyperloop" transportation system based on capsules zipping through depressurized tubes, much was made about the enormous technical challenges the system would face in development. However, that didn't stop a number of companies and organizations from starting to work on it. Several companies are pushing the development work hard, and it's shaping up like a race to a workable prototype. University teams are only increasing their efforts as well. "The Illinois team enters the SpaceX contest with a strong competitive edge. This is its fourth Hyperloop design project, the first dating to fall 2013, and the Hyperloop is now a part of the MechSE curriculum. The team has assembled an interdisciplinary network of faculty from aeronautical engineering, thermal dynamics, mechanical engineering, electronic engineering and software, and two of the team members have interned at SpaceX."

Comments

The pod has been pressurized to minimize the G

[trout007]

"The pod has been pressurized to minimize the G forces effects on a passenger."

Really? How is that little trick performed?

Re:The pod has been pressurized to minimize the G

[hey!]

"The pod has been pressurized to minimize the G forces effects on a passenger."

Really? How is that little trick performed?

Simple: they depolarize the tachyon flow to the defector dish. It's almost like you've never even seen an episode.

An even better design?

[goombah99]

they should bury it so it can be a straight line tube cutting into the earth's curvature. Then you can just "fall" from Los Angeles to SF with no propulsion needed. The theoretical transit time, ignoring the friction, is 43 minutes. the energy you need to supply is to overcome the friction. Since gravity will be both accelerating this and decelerating this there's no need for a complex propulsion system, decelleration system with energy reclamation. Less to go wrong, and less abrupt acceleration of the passengers, and probably greater safety.
Of course the hard part of this is you have to tunnel underground to make a straight line cutting in to the earth. Since LA to SF is about 400 miles along the surface and the earth's circumference is about 25000 miles this means arc length is about 0.016 radians. thus 25000/2/pi*(1-cos(0.016/2)) = 0.127 miles.
so the center of this would be roughly 1/8th of a mile buried or 672 feet at the deepest point (ignoring the mountains). This doesn't seem radically crazy as a depth for boring a hole.

Re:An even better design?

[Scottingham]

Then you can just "fall" from Los Angeles to SF with no propulsion needed.

I've found that if you use the word 'just' when describing anything related to engineering it's WAY more complex than you think it is, and usually impossible.

Huckleberry Musk

[Thud457]

boy, painting this fence is really fun.

I wonder if it can aid in space launches.

[SharpFang]

Imagine a section of tube going splitting away from the main network. It has an airlock shortly after the split, then gently curves up a tunnel through a mountain, and exits at a rather steep angle upwards. Then there's a quick-acting airlock at the opening.

A special train is loaded - a rocket adapted to travel through these tubes. It speeds up to the regular Mach 1 in the "civilian" section of the tunnel, then goes down the branch and gains another 2-3 Mach. The airlock at the end opens right before the rocket reaches it, then the hyperloop propulsion module drops on a parachute while the rocket ignites its engines. We've just shaved off first 1.5km/s out of the required 9 or so needed to reach orbit - and with the tyranny of rocket equation, that's quite a bit of savings!

Re:other enormous challenges not considered.

[SharpFang]

What percentage of Americans consider flying with commercial airlines to be the mark of poverty?

Hyperloop isn't a replacement for buses or city cars. It's a replacement for airplanes. Supersonic travel with high initial but low unit cost - airplanes are very wasteful because they need to use a lot of energy just to prevent falling. Hyperloop train, once running, keeps running with only minimal friction losses and can recuperate most of energy used on acceleration during braking.

It actually drives a lot of funds towards science/education. But yeah, the initial investment is huge. I mean, something like, 6% the amount any of the wars USA started!

Literally

[bravecanadian]

a pipe dream..

Re:.. pressurized to minimize the G forces effects

[Rei]

The author doesn't know what G-forces are, that's all. They were trying to say that the person isn't exposed to a vacuum.