He also recently said it's "a cross between a Concorde and a rail gun". That would at least enforce the maglev principle Jacques envisioned. It wouldn't be quite a Concorde in the pressurized tube though. But it's not impossibly far away from that concept, maybe Musk deliberately described it in a bit mysterious fashion. Time will tell.
Or a continuous maglev force (as the OP wrote) for the entire track, augmented with air pressure to store acceleration energy in the system for the other trains.
How much air pressure and track length would you need to accelerate a craft like this to supersonic speeds? ponders. Come to think of it, would that even be physically possible? My understanding of the "sonic boom" phenomenon is that it involves the craft breaking through a zone of high air pressure that has accumulated in front of it... Surely this wouldn't be possible if the pressure itself were propelling the craft. My (uninformed) guess would be that supersonic speeds are attainable with this kind of system, but probably unfeasible, and crafts probably wouldn't experience the sonic boom phenomenon.
He also said that there aren't any rails and it runs on the ground. At the moment, we have a Concorde without wings[0] (a lifting body Concorde, perhaps?) crossed with a railgun without rails. Sounds like vaporware.
[0]: It could still have wings but operate under ground effect, though it seems that it would be difficult to keep your leading edge intact travelling just above a hard surface "twice as fast as an airliner". "Twice as fast as an airliner" is Mach 0.85 * 2 = Mach 1.7 at FL360, which translates into Mach 1.5 at sea level. One useful thing we learn from this is that this system will basically have to be propelled by compressed air or electromagnetic force, since props don't work over Mach 1 and we don't have electric turbines.
Hmm, well I guess roads are cheaper than rails (i.e. rails along the entire route of the trip, not speed up rails like in a rail gun). And powering something from fixed locations (guns) is cheaper than bringing your engine with you.
So maybe it is like a train, one person per, but it runs on cheap road like track, and it's propulsion is provided by fixed stations. If each track was a straight run from station to station you could just ditch the wheels and whatnot and fire the thing between stations along the ground.
There's no way it could move so fast and still use car roads, unfortunately, so it will still have problems buying track space or building tunnels or building elevated paths. Too bad it runs on the ground.
> Hmm, well I guess roads are cheaper than rails [...]
We could look that up. But considering that roads and rails the world over are often build by governments or government owned corporations, I expect Elon Musk to have found a much cheaper way to build his infrastructure.
...the first bit of Hyperloop speculation that actually makes sense and seems plausible ...though the price will this will likely go up because it's new and untested technology and it has to be SAFE: the price difference between "doing something" and "doing something safely" can be orders of magnitude (think airplane safety) so I wouldn't rush to invest in it though...
The good thing is, this kind of system can be well tested before entering the market, because it does not rely on human intervention. Meaning, you test exactly the conditions you will always have.
Just like everything else in life the system would be subject to the laws of thermodynamics. The act of pressurising air would heat it up, and heat loss would mean that it wouldn't be fully reversible.
I suspect that a fully evacuated system using magnetic propulsion and energy recovery would be more efficient - the turbulent nature of air and the low-quality nature of heat energy would probably work against you to make a pneumatic spring fairly inefficient.
I don't think there's much doubt that an evacuated tube would be very efficient. Not only that, but you could go much faster. Jacques has rejected that hypothesis for other reasons.
sorry for being kind of a buzz kill - but I'd rather see elon musk venture away from traditional engineering ventures and going into life sciences. the hyperloop seems like an interesting concept, but I don't really see where it fits in, given that his electrical revolution of individual transportation succeeds. Very densely populated areas like new york are already reasonably served by a metro - scaling that system might be cheaper and equally effective as the hyperloop described by jacques mattheij. building new tunnels is very expensive and would probably account for most of the costs in this endeavor. additionally finding spare space in dense cities to construct such a hyperloop might be very difficult besides existing sewer systems and electrical lines, offsetting the benefits of the hyperloop (after all this would require massive public funding)
expanding this system to long distances would be really interesting, however even more expensive, given the need to construct long tunnels or tubes.
Musk has said that he doesn't want to be involved in Hyperloop, and after publishing it next month will just leave it up to others to build/test/commercialise/etc. I guess he doesn't have much time being two CEOs and a CTO.
The purpose of new innovations is to improve something. It's possible that in the very short term something like wouldn't be the most cost effective thing, however it's not about the very short term, but rather about the potential. In most existing transportation systems, the potential of the system without large changes has probably mostly been realized. The potential of something like this may be much larger, which is why it would be worthwhile.
my overall point is that I would rather see musk devoting his time to more promising and (in my opinion) more valuable projects (which danpalmer just said he would)
Re: "no rails" - perhaps it reduces friction by not touching the ground, via a combination of a railgun propulsion + airfoil. Thus, not needing continuous maglev for levitation. Also explains the "concord" comparison.
I'm thinking:
- Air based, but near the ground
- The vehicle is concord shaped
- Vehicle is launched into the air via rail gun (like a fighter jet on a ship: http://en.wikipedia.org/wiki/Electromagnetic_Aircraft_Launch...)
- Lots of boosting strips a few KMs apart.
- Based on the rail gun concept, the same "boosting" strip could also slow down or speed up a vehicle
- It removes the need for anything between the stations except open space.
- Minimal on-vehicle propulsion - otherwise I imagine the constant accelerate/decelerate would be a little unbearable for human flight
- Failure mode of the vehicle is to glide to a landing (though could magnetic eddy currents be used for breaking in a rail gun with minimal/no current?)
- The loop could refer to the idea of a continual loop of boosters, in opposite directions, removing the need for large "turn around" stations at either end
to go between LA and SF in 30 minutes you'll need to approach the speed of sound. Certainly self driving cars don't fit that category. Also Musk talked about it as a 5th mode of transportation, not sure if cars would cut it.
“Cheaper than high speed rail” - why is high speed rail expensive? I believe because precision contact between rail and wheel is required. How would this be done cheaper in a tunnel?
One issue with a tunnel is that even if the air and carriages are moving at the same speed, there is still drag or friction between the air and the wall of the tunnel by Poissiulle's law. At the proposed speeds (~300km/h) and distances (600km), this becomes a lot, and higher pressures (if my quick calculations are right) lead to higher energy requirements through higher air density.
In a vacuum, this friction would not exist. I can post my calcs if there is interest - I used a Moody chart and Darcy's friction equation, and ended up with an energy requirement that there would have to be ~80 million carriages going each way to be as efficient as a Telsa roadster, and neglecting any other losses.
600 kilometers / 80 million carriages gives me 7.5 mm per carriage length so I think there is a bit of a problem with that calculation.
The limiting case is when the whole tube is full of carriages, say they're 4 meters long that would mean there are a maximum of 150,000 carriages in that 600 Km long tube at absolute maximum capacity, something that you probably should not want to get close to.
More realistically, a regular roadway has a spacing of about 30 meters per vehicle at 60 Mph, you might be able to pack them in that tight in a tube like this but that's still pretty tight and leaves very little room for error when shifting carriages in and out of the loop.
At that spacing you could stuff (600,000 / 34) = 17650 carriages in (none of those assembled into impromptu trains, which of course would increase the density).
If we assume train like assemblies of 10 cars with 30 meter spacing you'd be looking at a 40 meter train + spacing is 70 meters, or 8500 trains, so 85000 carriages.
Those would then be pushing a column of of air 30 meters long ahead of them.
I was trying to compare the energy required to overcome friction of the air against the tunnel to driving the route conventionally. 80 million is an excessive number to expect want to travel at one time, which implies that driving is much more efficient from an energy required perspective.
Yes, I got that, but the fact that there isn't room in there for that many carriages means that the friction can't be that high. Unless there is a way in which the friction in a tube is so high that the little bit of air surrounding the vehicle would exert that much drag on the tunnel wall (so one vehicle length + say a few mm distance to the tunnel wall).
I'm not sure what the figure should be but this seems very high.
When fluids flow, there is a `no slip` condition at surfaces - that is the velocity of fluid at a surface is the same as the surface`s velocity. So in a stationary tunnel, the fluid may be moving at an average of 300 meters per second, but will be stationary at the wall. This makes a shear stress in the fluid and is what causes drag. In fact, making the air gap between the carraige and wall smaller will increase this drag since there is less distance for this transition to happen between stopped and fully moving air.
Consider if each carriage is pulling 30m of air a long distance at great speed. Consider if instead of the air moving against a stationary tunnel, a 30 meter section of tunnel was moving at the same distance and speed through stationary air. The drag on this would be high, much higher than a car at highway speeds.
What if it isn't air, but an actual fluid, e.g. water? It cannot be compressed, so it's "crash proof" (carriages cannot hit other carriages with water in between). It also has plenty of mass, so once it has started moving, it will push carriages around easily. A torus with permanently moving water (probably a more high-tech fluid), where carriages are injected / removed after acceleration / before deceleration?
Both liquids and gasses are fluids and drag is worse in water than air, so the energy required would only be higher. Consider: is it harder to push your hand through the air or a tub of water?
Rail is also expensive because it needs track the entire length of the trip. Huge problems on the west coast right now running rail where it is wanted because you need the land...
What if we fill the whole tube with carriages, without any space between them and very little space between the carriage wall and the tunnel wall? That would leave much less room for turbulence and perhaps reduce friction.
If that works, you could then have "station" sections where you could place/remove "inner" carriages to/from the carriages running inside the loop and thus you'd never have to disconnect the main carriage loop.
That's what I meant by using the carriages as the impellers, so effectively they push against the air in front of them up to the next carriage, which pulls on this air because it leaves a partial vacuum behind it. So there is no external source of pressure, it's just the carriages moving and 'drafting' in each others wake.
There will still be resistance though, both from the walls as well as leakage between the carriage and the walls (there can't be a really good seal there or the friction between the carriage and the wall would become too large, and since the wall is stationary and the carriage is moving very fast this friction is likely sizeable).
However, somehow using pressurized tubes for mail failed in the long run. I find those very fascinating, and apparently once upon a time some big cities were actually connected with a lot of such pressure tubes for sending mail. But apparently they were too unreliable and ended up going into oblivion.
Would be interesting if some of them could be resurrected somehow.
Another idea for improving transport: with modern technology better routing should be possible. Instead of all people boarding the same train that stops at every station, why not only board a carriage that goes directly to your destination? That could save a lot of time, I think.
I think your second idea is closer to what I think matches the things known about Hyperloop. I am convinced that electric (or hybrid) cars that self drive along beacons is the obvious next step in human urban transportation. These follow loops, like bus routes, that will pick you up when you get to a location along the loop since you have requested it (e.g. phone app) and drop you off at say a station, or another loop intersection where you can get into another loop vehicle, a loop bus or train at a scheduled and managed time. It can send the right size and amount of vehicles out of the depot into loop depending on how many people want to get on during a cycle, it can park the electric vehicles to charge at the right time. To the user it's a matter of saying 'I want to get to the conference at 9am' and the system will tell him what time a car will pick him up at his chosen pickup point.
Absolutely, and since Musk has an electric car company, something along those lines might be quite realistic. For electric cars used in that way, charging would not be an issue, as it would not be the burden of private car owners.
I just had another thought, although maybe a bit ridiculous: the main issue with "public cars" to me seems to me hygienic, how to keep them clean. What if in the future instead of owning whole cars, you only own a capsule with seats that can be picked up by transporters? I'd still prefer a world where parked car things are completely gone, but such capsules might still save a lot of space in the meantime.
I have a problem with the quote "no rails required" because I would interpret that in a general sense, i.e. a Car does not need rails. To me, a tube just sounds like a special kind of rail.
However, all the most plausible theories I have heard so far, and my own possibility, all rely on some sort of (although not traditional) rails.
Making the tunnel fit the carrage = no room for emergency
Security (terrorists + bomb = nightmare at speed of sound)
Windows? What would you look at?
If he thinking of just goods (not people) then some of these problems are much simpler - the tunnel could be less than 1m in radius.
My wild idea is that he is going to us a rail gun to fire drones up a couple of KM into the air, these then glide down to mini airports. Replace freight railroads.
People don't like windmills because they are "ugly".
They don't like power-lines in the country side.
They certainly wouldn't like a 2.5M+ diameter tube running around. In London, 56% (IIRC) of the "Underground" is above ground, much of that above road level.
we have a lot of wind turbines where I live. You get a strobe sounds of wuh-wuh-wuh-wuh-wuh if you are down wind of them. They are noisy. Also, if the sunlight catches them you also get a strobe reflection off them. That is also horrible.
There is a farmer who has 2 turbines up, he lives on the far side of a hill about a km away - you can still hear those whoosh-whoosh-whoosh all day long. Painful.
Powerlines also run over a lot of campsites near my house, you can hear them hummmmmm and crackle. In the damp/rain/mist/fog you can hear a lot of crackling and humming from them.
I can understand why people get angry with them. In urban areas where there is a lot of noise, I guess you wouldn't notice it so much.
Off topic, but my sister worked in a place where they put the magnets into wind turbines. There was a loud crash one day, someone had a magnet on a pallet, lifted it with a forklift and drove it out to a van. Half way the magnet got sucked by another magnet (in one of the factories) and burst through the wall and the two clamped together. They never got them apart and had to take the remaining bits of the turbine apart from around them.
> Off topic, but my sister worked in a place where they put the magnets into wind turbines. There was a loud crash one day, someone had a magnet on a pallet, lifted it with a forklift and drove it out to a van. Half way the magnet got sucked by another magnet (in one of the factories) and burst through the wall and the two clamped together. They never got them apart and had to take the remaining bits of the turbine apart from around them.
That's not it. From this article about Musk going to the UK[0], "it also can’t have a right of way issue, where people have to give up their homes." Your idea would be no different from high-speed rail in that regard.
How about underground? Pretty capital intensive and a lot more work than aboveground but it would get around the right-of-way issues. Access at various intervals would be very expensive though. But at least it would be possible (with a space based loop not so much).
Musk also said it would cost less than going by plane. Unless he has some novel approach to creating underground tunnels that's radically cheaper than existing methods, I don't see how this could be possible.
Interesting speculation by Jacques, but I think the combination of rail run and Concorde is a rail gun that fires hypersonic motor-less capsules that glide to destination.
Smaller landing zones, no air pollution, much less noise...
It's also a good combination of Telsa (rail gun) and SpaceX (rockets can be seen as motorized slugs).
Only limit I see with this system is that I'm not sure anyone could withstand the acceleration.
A sling would be much better for this: it's much smaller than a huge gun and also more flexible since the direction and elevation can be changed by altering the release point and axis.
Centripetal acceleration is a = v^2 / r so for 300 m/s (about mach 1) speeds, for 1 gee centripetal acceleration you'd need 9 km radius.
That makes quite a lot of sense. Air resistance could be a problem though. I guess if it was a loop, air could travel inside the tube but then you run into friction problems - it takes a lot of energy to keep the air running.
First time I read it wouldn't be an evacuated tunnel. Next thought of technology it could use then then jumps to maglev-like technology; Imagine a Tesla vehicle (or others) that can hop onto a network that brings the vehicle onto a maglev system, reducing friction (and other elements wouldn't really effect it, especially if you decided to put a canopy over it) ; Anyone else realize he may have dropped a hint in this video (http://video.ft.com/v/1974478965001/Elon-Musk-from-electric-... ) that we might see flying cars?
You'd need on-ramps, where a minimum speed is required before merging with the main line, and of course you'd only build on/off ramps at major hubs. The only issue I see being you're not using tar then, and therefore costs of raw materials would be higher, at least initially, and would likely last longer than tar.
Being cheaper than highspeed rail could fit into this equation because its the vehicle owners paying for the vehicle, and no trains are being build for it - so actual money going into the system, the synergies that would exist, might be greater - though putting it how he does is creating lots of attention. :)
Maybe the hyperloop refers to a an on/off ramping system, where you get accelerated to a certain speed... Fun speculating. And time for tea and breakfast.
All great points, but I will point out that the major cost item on high speed (or any rail for that matter) is the rail itself. The cars and locomotive are relatively cheap, but you're looking at figures of $1M+ USD per mile of track.
If/when self-driving cars succeed in being ready for public consumption, I think a huge opening for revolutions in transportation gets opened up.
- If you can call your car, it can park farther away. Parking is one of the biggest problems with cars in urban areas.
- Instead of calling of your car, you could just call a car. A self driving car and a self driving taxi are pretty similar, but one can run 24hrs and reduce the parking problem more.
- Computers can do things people can't do. Once enough auto-automobiles are out there, there can be autoauto only "features". The same square footage of tarmac might be able to move cars much quicker. Maybe autoautos can handle 200km speeds. Maybe they can cooperate to make traffic smoother. Maybe they can link together like trains to overcome congestion.
There is nothing quite as good as having a car to take you exactly to and from where you want to go. If self driving cars can really mix with human drivers everywhere they may have a nice smooth path to innovate on gradually. Big vision plans for revolutionizing transport are so centralized, so premeditated.
edit: one more thing. self driving cars interact in an interesting way with public/mass trasport, especially if people dont own their own. It may reduce the demand by competing more directly on one hand. OTOH, it will compliment by providing the last-mile component.
I honestly don't think delivery drones are going to be a widespread thing. Too many problems that you can encounter that lose you an expensive drone that wouldn't lose you a simple high school age delivery driver.
Yeah. They would probably have to be cleaned pretty regularly.
It's terrible to think that people invent cars, then make them driverless, then make them come pick you up from anywhere when you whistle (or press a button on your phone) but the bottleneck that we can't solve is inconsiderate assholes leaving fish and chip rubbish in the back seat.
OK, we are in agreement then. For some reason I thought you meant charging more for wanting a clean vehicle. I'd rather charge more for people who leave the car in a messy state (because they are in a hurry or something)
In almost two years of being a ZipCar client, I've never had any issues. Yes, the occasional coke can or candy wrapper left behind, but never a mess that I thought to be unreasonable.
If it turns out to be a bigger problem, install a camera that takes a shot when you take possession of the car, and when you relinquish it. Charge the renters credit card for messiness.
> install a camera that takes a shot when you take possession of the car, and when you relinquish it.
Such a system would be good to have anyway as part of a dashcam. One facing forward, and a fish-eye facing the rear window and also capturing the interior of the car. I am hoping that car insurance companies will start offering discounts for cars with installed dashcams.
A tangent of a tangent now, this would be great (though creepy) for public restrooms. Given that there's a physical method, like positioning on the door, that prohibits it from seeing anything while the stall door is closed or locked, I think it would cut down on the seriously depraved messes people leave behind when they know they can get away with it.
Maybe they can dent the number of fatalities from human error. There is a hurdle in overcoming public perception. People say they wouldn't want to put their life in control of some automated computer, yet they put their life in the hands of thousands of other drivers every single day they drive.
In the US we accept 10000 fatalities annually from drunk drivers alone. Vietnam killed nearly 60000 and wounded countless others over the course of 20 years. In just the last 20 we've accepted more than 200,000 alcohol related deaths just getting from point A to point B.
So when people are afraid of a glitch in the system causing a pile up it is worth remembering such tragedies are possible, but it would still be something that could be corrected.
No matter how closely together the cars can drive, as long as you have an engine and a crash-resistant shell around each passenger, it will never be as space-efficient was the 35' Gillig Advantage I am sitting in right now.
IMO the best application of self-driving cars in an urban landscape is last-mile demand for people who live outside the city, where it's not economical to run buses or trains. But inside a city proper, or even on a busy freeway, having one car per passenger takes up a lot of space that could be better used elsewhere, both while moving and while parked.
(Also, self-driving technology could be applied to buses and streetcars to reduce operating costs and expand frequency and range of service.)
Public transport minibuses might actually be a good place to exercise self driving vehicles.
Minibuses don't need the same versatility as consumer cars have. They "only" need to be able to handle anything they can encounter on a predefined route. The route itself could even be optimized for them (eg pedestrian barriers).
Preface: my primary modes of transportation (in my city) are walking, biking, and subway.
God, I cannot wait for either hyper loop or self driving cars (I'm sure we'll see the latter first). I live in Northern California and have family in Southern California. We're starting to flip the holidays this year (wife's family for thanksgiving, mine for Xmas). Just went down to LA for a friends wedding and the drive was horrendous.
A lot of factors come into play:
1, as much as I've hated them in the past, a big suv (especially with a kid) is the way to go. We have a VW Passat (wife's) and it was so crammed it was ridiculous. Very uncomfortable and it's not even a compact.
2, I'm over 40 now and it just physically hurts to drive for 7 hours. I was totally sore the next day. Frickin sucked.
3, Directions. I totally need navigation now. Even with the turn by turn on my phone, I still made wrong turns.
4, I hate driving. Hate it. I see it as such a waste of time. I can't imagine needing to drive to make a living. In my late teens and early 20's when I lived in Southern California, I hade to do just that. After I moved to the city I vowed I never would again.
5, Other drivers. I was pretty appalled by some of the drivers on the road. I kept thinking, I can't wait for computers to handle this so that guy driving down the emergency lane wouldn't be able to.
If I could just hop in a driverless car for that drive, it would be great. I could nap, read, compute, converse, etc. Things I can't do now. I'm sure there's going to be some resistance at first by those with a 'god given right' to drive. But after a while, I see common sense prevailing.
I listened to a great talk at The Long Now Foundation by Tim O'Reilly. He was talking about driverless cars and how the DARPA car challenge when it started could only do around 7 miles. It wasn't the algorithms that got that much better (although I'm sure they did) for the Google cars, it was the data set. Google Maps was a huge advantage and the 'killer app' for the latest generation of their cars.
So a lot to look forward to in this arena. I think my kid will grow up with the internal combustion car for him being like the 8-track for me.
Though a rarely brought up fact when discussing self-driving vehicles, planes have been on the right track for the last few decades with autopilot. The automotive industry should take some lessons learned from the government regulatory structure, and avionic makers, and build a system capable of high capacity traffic with extremely low fatality rates.
Issues that we deal with when driving an automobile are amplified 100x when in the cockpit of an aircraft. Traffic is nearly impossible to spot during the day time without someone like an air traffic controller (ATC) telling you about it. Managing a plane in inclement weather is an effort in bravery and extraordinary situational decision making. Crashes, though statistically unlikely to be fatal, can have extreme consequences for both passengers an innocent by-standers. All-in-all, the experience of flying is just plain difficult. There are dozens of controls to handle at any given moment, and even the distractions are amplified (ever tried writing something down while driving? It happens in planes all the time)
So how did we overcome these issues? Regulations and technology. Just looking at the traffic issue, there are rules for which alititude to fly at for which direction and type of flight you are, rules for entering high traffic areas by verifying you have communicated intentions first, rules for what equipment your plane has to have before entering specific high traffic areas, and strict expectations that pilots will be able to control their aircraft to the best of their ability. There is plenty of redundancy in the system as well.
I would venture to say that landing a plane is much more demanding than driving a car, even in the most severe driving conditions, yet we trust autopilots to set the plane down in even the most severe 0 visibility scenarios (http://www.youtube.com/watch?v=7BUA3EwKpVM). The technology in vehicles is beginning to make sense to implement in the same way we have it present in airplanes right now, but I would love to see the regulatory structure begin to step up and build a reasonable, redundant, and safe system for driving an driver-less car. Then I can see the world you are describing.
Rather than self-driving cars, I see hype-loop kind of system being more effective overall(reliable, cheaper). Obviously a lot more work has been done(Google) on self-driving cars but I would secretly hope/wish that Elon really gets cracking on this thing(especially since he has to regular suffer one of the worst commutes in the world - 405 freeway in LA - especially that particular section).
Sorry to be the pernickety one, Jacque but inyour opening sentence: "For a while now there are tantalizing hints that Elon Musk is at it again." isn't correct English since "are" is the wrong tense.
Try "For a while now there have been tantalizing hints that Elon Musk is at it again"
Or perhaps better: "There have been tantalizing hints that Elon Musk is at it again for a while now"
If your sorry to be that guy, perhaps send Jacques an email instead of posting on a public forum. Unless your not so sorry that you had to be 'that' guy.
Looking to me like router/hub concept in the real world called Hyperloop. You have network (pressured tunnels) with packets (packets which carry me around Hyperloop) controlled via nodes aka router/hub (locations where people could board). Brilliant.
Sorry Jacques, I'm sticking to the suborbital maglev thing.
Yeah, I know it's a long-shot, but it fits into my idea of Musk better than a giant mail tube. I'm just seeing pressurized tubes scaling. There's the same problem with the orbital sub-loop, but I'm betting Musk spent a lot of time looking at this idea as part of his Mars dream.
One thing's for sure -- it's going to be a blast seeing how it all turns out!
Didn't he say in the Ariane 5 is dead interview that it's a cross between a Concorde and a rail gun, so think super streamlined glider, launched by maglev, captured by maglev (recovering some energy energy on capture). High speed rail without most of the rail.
The big issue would be air traffic control at launch and landing. 600 m/s (Mach 2) at 0.5g acceleration would require 36km of launch rail which is kind of a lot. But you could loop the track and reduce the acceleration to make up for centripetal forces — a 200m radius loop might be about right, and once you use a loop you can go a lot faster (and this explains the name: hypersonic loop).
I suppose it might skip short distances requiring pylons or something for speed top ups and travel at lower speed.
I figure it is a side by side maglev with a bunch of mass going around one of the tracks to store energy.
That's assuming the mass needs to be on a second track to maintain a schedule. I guess it's probably possible to do something clever at the stations to avoid a second track.
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[ 26.9 ms ] story [ 5453 ms ] threadhttp://en.wikipedia.org/wiki/Railgun
Its just maglev trains with some novel enclosed design with carriage dissociation?
A bit like this chinese train concept that has drop off/pick up of carriages:*
*http://www.google.co.uk/url?sa=t&rct=j&q=&esrc=s...
[0]: It could still have wings but operate under ground effect, though it seems that it would be difficult to keep your leading edge intact travelling just above a hard surface "twice as fast as an airliner". "Twice as fast as an airliner" is Mach 0.85 * 2 = Mach 1.7 at FL360, which translates into Mach 1.5 at sea level. One useful thing we learn from this is that this system will basically have to be propelled by compressed air or electromagnetic force, since props don't work over Mach 1 and we don't have electric turbines.
So maybe it is like a train, one person per, but it runs on cheap road like track, and it's propulsion is provided by fixed stations. If each track was a straight run from station to station you could just ditch the wheels and whatnot and fire the thing between stations along the ground.
There's no way it could move so fast and still use car roads, unfortunately, so it will still have problems buying track space or building tunnels or building elevated paths. Too bad it runs on the ground.
We could look that up. But considering that roads and rails the world over are often build by governments or government owned corporations, I expect Elon Musk to have found a much cheaper way to build his infrastructure.
I always imagined Hyperloop as carriages pushed by a plasma armature, in a rail gun loop. just like a plasma-rail gun.
I suspect that a fully evacuated system using magnetic propulsion and energy recovery would be more efficient - the turbulent nature of air and the low-quality nature of heat energy would probably work against you to make a pneumatic spring fairly inefficient.
Specifically, due to a specific statement that it is not an evacuated tube.
I'm not really sure how it "can't crash", nor how there aren't any "rails" (or things that look suspiciously like rails).
expanding this system to long distances would be really interesting, however even more expensive, given the need to construct long tunnels or tubes.
Techwise, I still think the Lofstrom loop theory sounds the most likely: http://en.wikipedia.org/wiki/Launch_loop
The purpose of new innovations is to improve something. It's possible that in the very short term something like wouldn't be the most cost effective thing, however it's not about the very short term, but rather about the potential. In most existing transportation systems, the potential of the system without large changes has probably mostly been realized. The potential of something like this may be much larger, which is why it would be worthwhile.
One issue with a tunnel is that even if the air and carriages are moving at the same speed, there is still drag or friction between the air and the wall of the tunnel by Poissiulle's law. At the proposed speeds (~300km/h) and distances (600km), this becomes a lot, and higher pressures (if my quick calculations are right) lead to higher energy requirements through higher air density.
In a vacuum, this friction would not exist. I can post my calcs if there is interest - I used a Moody chart and Darcy's friction equation, and ended up with an energy requirement that there would have to be ~80 million carriages going each way to be as efficient as a Telsa roadster, and neglecting any other losses.
The limiting case is when the whole tube is full of carriages, say they're 4 meters long that would mean there are a maximum of 150,000 carriages in that 600 Km long tube at absolute maximum capacity, something that you probably should not want to get close to.
More realistically, a regular roadway has a spacing of about 30 meters per vehicle at 60 Mph, you might be able to pack them in that tight in a tube like this but that's still pretty tight and leaves very little room for error when shifting carriages in and out of the loop.
At that spacing you could stuff (600,000 / 34) = 17650 carriages in (none of those assembled into impromptu trains, which of course would increase the density).
If we assume train like assemblies of 10 cars with 30 meter spacing you'd be looking at a 40 meter train + spacing is 70 meters, or 8500 trains, so 85000 carriages.
Those would then be pushing a column of of air 30 meters long ahead of them.
I'm not sure what the figure should be but this seems very high.
Consider if each carriage is pulling 30m of air a long distance at great speed. Consider if instead of the air moving against a stationary tunnel, a 30 meter section of tunnel was moving at the same distance and speed through stationary air. The drag on this would be high, much higher than a car at highway speeds.
Consider a tub of water moving at the desired speed...
If that works, you could then have "station" sections where you could place/remove "inner" carriages to/from the carriages running inside the loop and thus you'd never have to disconnect the main carriage loop.
There will still be resistance though, both from the walls as well as leakage between the carriage and the walls (there can't be a really good seal there or the friction between the carriage and the wall would become too large, and since the wall is stationary and the carriage is moving very fast this friction is likely sizeable).
Would be interesting if some of them could be resurrected somehow.
Another idea for improving transport: with modern technology better routing should be possible. Instead of all people boarding the same train that stops at every station, why not only board a carriage that goes directly to your destination? That could save a lot of time, I think.
I just had another thought, although maybe a bit ridiculous: the main issue with "public cars" to me seems to me hygienic, how to keep them clean. What if in the future instead of owning whole cars, you only own a capsule with seats that can be picked up by transporters? I'd still prefer a world where parked car things are completely gone, but such capsules might still save a lot of space in the meantime.
http://en.wikipedia.org/wiki/Pneumatic_tube
However, all the most plausible theories I have heard so far, and my own possibility, all rely on some sort of (although not traditional) rails.
Digging a tunnel takes years and cost billions (see London underground new tunnel http://www.bbc.co.uk/news/business-16320945)
Making the tunnel fit the carrage = no room for emergency
Security (terrorists + bomb = nightmare at speed of sound)
Windows? What would you look at?
If he thinking of just goods (not people) then some of these problems are much simpler - the tunnel could be less than 1m in radius.
My wild idea is that he is going to us a rail gun to fire drones up a couple of KM into the air, these then glide down to mini airports. Replace freight railroads.
By this logic Planes are a bad idea too (no room for emergency, high speed, tiny windows with nothing to look at)...
They don't like power-lines in the country side.
They certainly wouldn't like a 2.5M+ diameter tube running around. In London, 56% (IIRC) of the "Underground" is above ground, much of that above road level.
There is a farmer who has 2 turbines up, he lives on the far side of a hill about a km away - you can still hear those whoosh-whoosh-whoosh all day long. Painful.
Powerlines also run over a lot of campsites near my house, you can hear them hummmmmm and crackle. In the damp/rain/mist/fog you can hear a lot of crackling and humming from them.
I can understand why people get angry with them. In urban areas where there is a lot of noise, I guess you wouldn't notice it so much.
Off topic, but my sister worked in a place where they put the magnets into wind turbines. There was a loud crash one day, someone had a magnet on a pallet, lifted it with a forklift and drove it out to a van. Half way the magnet got sucked by another magnet (in one of the factories) and burst through the wall and the two clamped together. They never got them apart and had to take the remaining bits of the turbine apart from around them.
What city was this in? Which manufacturer?
0: http://techcrunch.com/2012/11/19/elon-musk-with-jobs-gone-go...
Now I'm really curious...
Smaller landing zones, no air pollution, much less noise...
It's also a good combination of Telsa (rail gun) and SpaceX (rockets can be seen as motorized slugs).
Only limit I see with this system is that I'm not sure anyone could withstand the acceleration.
Centripetal acceleration is a = v^2 / r so for 300 m/s (about mach 1) speeds, for 1 gee centripetal acceleration you'd need 9 km radius.
http://dylanized.com/the-hyperloop/
You'd need on-ramps, where a minimum speed is required before merging with the main line, and of course you'd only build on/off ramps at major hubs. The only issue I see being you're not using tar then, and therefore costs of raw materials would be higher, at least initially, and would likely last longer than tar.
Being cheaper than highspeed rail could fit into this equation because its the vehicle owners paying for the vehicle, and no trains are being build for it - so actual money going into the system, the synergies that would exist, might be greater - though putting it how he does is creating lots of attention. :)
Maybe the hyperloop refers to a an on/off ramping system, where you get accelerated to a certain speed... Fun speculating. And time for tea and breakfast.
- If you can call your car, it can park farther away. Parking is one of the biggest problems with cars in urban areas.
- Instead of calling of your car, you could just call a car. A self driving car and a self driving taxi are pretty similar, but one can run 24hrs and reduce the parking problem more.
- Computers can do things people can't do. Once enough auto-automobiles are out there, there can be autoauto only "features". The same square footage of tarmac might be able to move cars much quicker. Maybe autoautos can handle 200km speeds. Maybe they can cooperate to make traffic smoother. Maybe they can link together like trains to overcome congestion.
There is nothing quite as good as having a car to take you exactly to and from where you want to go. If self driving cars can really mix with human drivers everywhere they may have a nice smooth path to innovate on gradually. Big vision plans for revolutionizing transport are so centralized, so premeditated.
edit: one more thing. self driving cars interact in an interesting way with public/mass trasport, especially if people dont own their own. It may reduce the demand by competing more directly on one hand. OTOH, it will compliment by providing the last-mile component.
It's terrible to think that people invent cars, then make them driverless, then make them come pick you up from anywhere when you whistle (or press a button on your phone) but the bottleneck that we can't solve is inconsiderate assholes leaving fish and chip rubbish in the back seat.
- reputation systems
- computer vision / cameras / contract law
- price discrimination based on the required state of the vehicle (i.e., premium pricing for a guarantee that a vehicle has been cleaned)
But yeah, I do think we agree :)
In almost two years of being a ZipCar client, I've never had any issues. Yes, the occasional coke can or candy wrapper left behind, but never a mess that I thought to be unreasonable.
If it turns out to be a bigger problem, install a camera that takes a shot when you take possession of the car, and when you relinquish it. Charge the renters credit card for messiness.
Such a system would be good to have anyway as part of a dashcam. One facing forward, and a fish-eye facing the rear window and also capturing the interior of the car. I am hoping that car insurance companies will start offering discounts for cars with installed dashcams.
A tangent of a tangent now, this would be great (though creepy) for public restrooms. Given that there's a physical method, like positioning on the door, that prohibits it from seeing anything while the stall door is closed or locked, I think it would cut down on the seriously depraved messes people leave behind when they know they can get away with it.
In the US we accept 10000 fatalities annually from drunk drivers alone. Vietnam killed nearly 60000 and wounded countless others over the course of 20 years. In just the last 20 we've accepted more than 200,000 alcohol related deaths just getting from point A to point B.
So when people are afraid of a glitch in the system causing a pile up it is worth remembering such tragedies are possible, but it would still be something that could be corrected.
IMO the best application of self-driving cars in an urban landscape is last-mile demand for people who live outside the city, where it's not economical to run buses or trains. But inside a city proper, or even on a busy freeway, having one car per passenger takes up a lot of space that could be better used elsewhere, both while moving and while parked.
(Also, self-driving technology could be applied to buses and streetcars to reduce operating costs and expand frequency and range of service.)
Minibuses don't need the same versatility as consumer cars have. They "only" need to be able to handle anything they can encounter on a predefined route. The route itself could even be optimized for them (eg pedestrian barriers).
And:
- On a long journey, you can read, watch a film, surf the net or sleep. Overnighters become an option.
- Too drunk to drive yourself home? No problem. Too young? Likewise.
- No driver's licence? No problem. A driver's licence may eventually become a niche thing to have, like a pilot's licence.
You can do more with normal cars today, already. (In fact, I've done so.) The economics of those speeds just don't add up for cars.
God, I cannot wait for either hyper loop or self driving cars (I'm sure we'll see the latter first). I live in Northern California and have family in Southern California. We're starting to flip the holidays this year (wife's family for thanksgiving, mine for Xmas). Just went down to LA for a friends wedding and the drive was horrendous.
A lot of factors come into play:
1, as much as I've hated them in the past, a big suv (especially with a kid) is the way to go. We have a VW Passat (wife's) and it was so crammed it was ridiculous. Very uncomfortable and it's not even a compact. 2, I'm over 40 now and it just physically hurts to drive for 7 hours. I was totally sore the next day. Frickin sucked. 3, Directions. I totally need navigation now. Even with the turn by turn on my phone, I still made wrong turns. 4, I hate driving. Hate it. I see it as such a waste of time. I can't imagine needing to drive to make a living. In my late teens and early 20's when I lived in Southern California, I hade to do just that. After I moved to the city I vowed I never would again. 5, Other drivers. I was pretty appalled by some of the drivers on the road. I kept thinking, I can't wait for computers to handle this so that guy driving down the emergency lane wouldn't be able to.
If I could just hop in a driverless car for that drive, it would be great. I could nap, read, compute, converse, etc. Things I can't do now. I'm sure there's going to be some resistance at first by those with a 'god given right' to drive. But after a while, I see common sense prevailing.
I listened to a great talk at The Long Now Foundation by Tim O'Reilly. He was talking about driverless cars and how the DARPA car challenge when it started could only do around 7 miles. It wasn't the algorithms that got that much better (although I'm sure they did) for the Google cars, it was the data set. Google Maps was a huge advantage and the 'killer app' for the latest generation of their cars.
So a lot to look forward to in this arena. I think my kid will grow up with the internal combustion car for him being like the 8-track for me.
Issues that we deal with when driving an automobile are amplified 100x when in the cockpit of an aircraft. Traffic is nearly impossible to spot during the day time without someone like an air traffic controller (ATC) telling you about it. Managing a plane in inclement weather is an effort in bravery and extraordinary situational decision making. Crashes, though statistically unlikely to be fatal, can have extreme consequences for both passengers an innocent by-standers. All-in-all, the experience of flying is just plain difficult. There are dozens of controls to handle at any given moment, and even the distractions are amplified (ever tried writing something down while driving? It happens in planes all the time)
So how did we overcome these issues? Regulations and technology. Just looking at the traffic issue, there are rules for which alititude to fly at for which direction and type of flight you are, rules for entering high traffic areas by verifying you have communicated intentions first, rules for what equipment your plane has to have before entering specific high traffic areas, and strict expectations that pilots will be able to control their aircraft to the best of their ability. There is plenty of redundancy in the system as well.
I would venture to say that landing a plane is much more demanding than driving a car, even in the most severe driving conditions, yet we trust autopilots to set the plane down in even the most severe 0 visibility scenarios (http://www.youtube.com/watch?v=7BUA3EwKpVM). The technology in vehicles is beginning to make sense to implement in the same way we have it present in airplanes right now, but I would love to see the regulatory structure begin to step up and build a reasonable, redundant, and safe system for driving an driver-less car. Then I can see the world you are describing.
Try "For a while now there have been tantalizing hints that Elon Musk is at it again"
Or perhaps better: "There have been tantalizing hints that Elon Musk is at it again for a while now"
Yeah, I know it's a long-shot, but it fits into my idea of Musk better than a giant mail tube. I'm just seeing pressurized tubes scaling. There's the same problem with the orbital sub-loop, but I'm betting Musk spent a lot of time looking at this idea as part of his Mars dream.
One thing's for sure -- it's going to be a blast seeing how it all turns out!
The big issue would be air traffic control at launch and landing. 600 m/s (Mach 2) at 0.5g acceleration would require 36km of launch rail which is kind of a lot. But you could loop the track and reduce the acceleration to make up for centripetal forces — a 200m radius loop might be about right, and once you use a loop you can go a lot faster (and this explains the name: hypersonic loop).
I suppose it might skip short distances requiring pylons or something for speed top ups and travel at lower speed.
That's assuming the mass needs to be on a second track to maintain a schedule. I guess it's probably possible to do something clever at the stations to avoid a second track.