Hyperloop

[VolkerP]

@Norbert good points. Power usage can only be kept in sensible range when the acceleration pads have limited extend.

OTOH Don't bring your laptop with (conventional) hard drive, or pacemaker near magnetic field created by 1m Amps. I once stood near a physics experiment with 1 Tesla magnetic field inside. The stray fields outside the superconducting coil made the keys in my pocket turn - in 5ft distance.

 

[Johan]

I'm an MD, normally GP but currently doing a one year rotation at the hospital working as a neurologist. We do a lot of MRI. Our best machines have fields of 3 Tesla. Those machines will literally suck your keys out of your pocket! Needless to say you can't have an MRI if you have a pacemaker. And not if you have magnetic metal shrapnels or the like in your body.

Here's an image of a woman with some keys on a chain close to an MRI scanner:

.

 

[Norbert]

Now that the discussion took this turn, Elon might have to assure us it is laptop-compatble... :wink:

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@Norbert good points. Power usage can only be kept in sensible range when the acceleration pads have limited extend.

I'm more expecting that the application of power will be continuous and therefore smaller, however that will be accomplished.

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We do a lot of MRI.

How much power do they consume?

 

[TEG]

A "loop"?

Looks like he got stuck in the loop: :tongue:

 

[Johan]

How much power do they consume?

I had to look it up and ask a radiologist. Basically they say it uses about 1-3 kWh per scan, depending on protocol and which area you're scanning. However, this is in a very short time period so the power is very large. I know for a fact they they are hooked up to a 400V/150A/3-phase system (let's say it draws 100Amps during scan, at 400V, 3 phase, that's 70kW). Almost like a SuperCharger

One thing though is you don't ever (almost) shut an MRI machine off, since it takes a lot of time and energy to worm it up and to generate the magnetic field. If I go to the floor below the MRI's you can hear the humming 24 hours a day. Also, they wan't to use them as much as possible since they draw a lot of energy jus sitting idle. I think once they had to power it off for some reason and we couldn't use that machine until next day, so it takes quite some time to "worm up". Maybe someone here with better detailed knowledge than me can chime in?

Here's an image about yearly power usage of a regular (1.5 Tesla) machine I found on Siemens site (note this takes in to account production of the machine and 10 years of usage):

 

[dpeilow]

So a magnetically propelled vehicle that goes very fast and can't crash?

(Except this one did, but only due to extreme negligence and stupidity)

 

[Norbert]

So a magnetically propelled vehicle that goes very fast and can't crash?

I guess it means "faster than an airplane, but can't crash like an airplane can". (Only like a train.)

 

[VolkerP]

It's silly to say something moving can't crash. Like saying a ocean going ship is unsinkable.

Definition of crash = two objects, at least one of them moveable, trying to occupy the same spot at the same time :smile:

 

[drinkerofkoolaid]

Could it be something like the below picture?

I'm visualizing this kind of image and assuming it runs on command based interface where you input your destination, press go, and it handles the rest. You pay when you leave, based on how far you went, or something like this. In theory if a computer is handling the driving, and assuming it is only on one track, it could be virtually impossible to crash. It kind of reminds me of rides at Universal Studios. Making it solar powered should be fairly straight forward. If he's calling it the hyper-loop, one would assume it is a circular rail "loop", that moves very fast "hyper". (Not to state the obvious) I'm imagining a mono-rail that utilizes something like the below picture. In theory, it would be impossible to crash. (Short of computer malfunction). If it operates on one track, and is automated, it could go as fast as they could make it capable of going safely.

 

[vfx]

So basically set up like an amusement park ride or a ski lift. Line up for groups of 5 or six to launch off for wild ride across the state.

 

[jcstp]

sounds a lot like PRT (Personal Rapid Transit)
Personal Rapid Transit (PRT) Information


home | Ultra Global PRT

 

[TEG]

From 1992: Popular Science - Google Books

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From 2004: Popular Science 4000 MPH vac train.

(I know, Hyperloop is "not a vac train"...)

 

[Yggdrasill]

I have one idea about what it could be.

If you have a row of towers, where there's a "railgun" at the top of each tower, you could be able to fire a capsule from tower to tower. The towers could be spaced at just the right distances, so that the capsule doesn't have time to veer off course before the next tower corrects the trajectory. And the faster the capsule goes, the more momentum, and the further apart the towers can be. This reduces land usage, so it could potentially be cheaper than rail in populated areas, and it should be able to achieve fairly high speeds.

I'm not sure why it wouldn't be able to crash, though.

 

[TEG]

...Aircraft are discouraged from flying between the towers because a human filled projectile could be speeding past at supersonic speeds...

 

[Yggdrasill]

I have one idea about what it could be.

If you have a row of towers, where there's a "railgun" at the top of each tower, you could be able to fire a capsule from tower to tower. The towers could be spaced at just the right distances, so that the capsule doesn't have time to veer off course before the next tower corrects the trajectory. And the faster the capsule goes, the more momentum, and the further apart the towers can be. This reduces land usage, so it could potentially be cheaper than rail in populated areas, and it should be able to achieve fairly high speeds.

Or another idea:

If you remove the railguns, string a cable between the towers, use magnetic bearings to levitate the cable, and accelerate the cable to supersonic speeds, you get a system that is less prone to crash, can store energy in the cable, and pods could be able to magnetically attach to the cable to whizz from one station to the next. This should also allow towers to be further apart, at least at slower speeds near stations. As the cable itself has oodles of momentum, the centripetal force would want to push the cable into a perfect circle, so it might be necessary to built the towers in an approximately circular shape. Two loops of cable would be good, one in each direction.

 

[WhiteKnight]

Two loops of cable would be good, one in each direction.

Maybe that's why it would be called hyperLOOP.

 

[RDoc]

Or another idea:

If you remove the railguns, string a cable between the towers, use magnetic bearings to levitate the cable, and accelerate the cable to supersonic speeds, you get a system that is less prone to crash, can store energy in the cable, and pods could be able to magnetically attach to the cable to whizz from one station to the next. This should also allow towers to be further apart, at least at slower speeds near stations. As the cable itself has oodles of momentum, the centripetal force would want to push the cable into a perfect circle, so it might be necessary to built the towers in an approximately circular shape. Two loops of cable would be good, one in each direction.

To do that though, the cables would have to be moving at orbital speed, that is around mach 22, which would be tough in the atmosphere. There' a proposal for a space launch system like that: Lofstrom Loop

 

[Yggdrasill]

To do that though, the cables would have to be moving at orbital speed, that is around mach 22, which would be tough in the atmosphere. There' a proposal for a space launch system like that: Lofstrom Loop

No, you wouldn't need it to go that fast. Its purpose wouldn't be to launch anything into orbit, the purpose would merely be to move stuff from one place to the next at high speeds. It would basically be a suped-up gondola lift, with cables moving at supersonic speeds (or more realistically, high sub-sonic).

 

[keys]

I'm still a skeptic about any existing alternative (vac tunnel, maglev, tube transport etc).. Main concern is amount of raw material and therewith costs. Also, you probably don't want to elevate the system since this causes major alignment issues (specifically at mach 1~2).

The ground-based concorde is interesting. I think you could dig a long ditch in the ground and reinforce & cover it with some prefab sections. This way you could solve or at least alleviate concerns regarding the sonic boom. Next you would have this some sort of cart that 'floats' through the tunnel. Propulsion could be done using a supersonic electric turbine powered from the structure itself. The knowledge gathered from creating this propulsion system could also be used inside an electric supersonic plane (which would use similar turbines). Not sure about the way to store massive amounts of energy without batteries.

 

[jeff_adams]

If I were Elon, I would think seriously about leveraging the DOE loan pay off for Hyperloop right now. He's going to be the darling of Washington. Here's what I would recommend:

Approach Obama Administration and offer to develop Hyperloop. Pledge 250 million if the government will match funds (he could easily sell some Tesla and Solar City shares to raise his portion right now). Hyperloop will need government assistance with Eminent Domain issues and approvals. 500m would be a great start. Elon can form a "think tank" and guide them in the direction he thinks is best. His star is as bright as it's ever been. Now is the time to leverage that star power