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An 89-year-old Reinventing the Train in His Backyard (wired.com)
154 points by cdvonstinkpot 7 days ago | hide | past | web | 60 comments | favorite





The idea of a magnetic coupling between the engine and the passenger compartment is very interesting. This could be adapted to use with self-driving automobiles on highways. They could run on their own electric power train for local journeys, then pick up a "thrust carriage" when joining a highway. This pulls them along until their exit, when they decouple and return to using their battery and on-board motors. The on-board motors could also take over for short sections for example between different thrust carriage runs.

Perhaps the thrust carriage control systems could be made smart so they automatically maintain safe spacing between vehicles and adapt their speed to the volume of traffic. They'd communicate with the vehicle to tell them when the coupling was about to end so that the vehicle can engage its own drive train to take over smoothly. Or the vehicle's self-driving systems tell the thrust carriage how fast to go depending on the traffic conditions.

This could massively extend the range of electric cars. Burying the pipes in the road network would obviously be very expensive, but the size mentioned in the article (12 inch diameter) is not prohibitive.


You wouldn't need a thrust carriage to get big fuel gains. It's enough that the cars form a tightly packed line as racing cyclists do to minimize drag to get major gains is fuel economy:

https://www.quora.com/How-much-does-aerodynamics-affect-fuel...


The changes in fuel economy mentioned in that article don't seem that big. On the other hand, if an electric car only needed batteries for a range of say 50km, that would be a large saving in cost and weight. The batteries are only needed for local journeys, and the thrust carriage mechanism provides almost all of the energy for long journeys.

It would probably require electrically driven thrust carriages rather than pneumatic - you would need one for every car using the system. Trucks might need 2 or 3 or more to provide enough thrust. If a magnetic coupling really works, it would be possible to attach and detach from the thrust carriage at motorway intersections without slowing down any more than cars do at the moment.


> It would probably require electrically driven thrust carriages rather than pneumatic - you would need one for every car using the system.

Not necessarily one per car. You'd probably have a chain of thrust carriages, with maybe some spacing in between each individual carriage. One or several cars would clump onto a thrust carriage -- there's nothing to prevent them from being quite long.

When it's time to get off the highway there might be a hole in the clump for a bit until someone getting onto the highway fills it in.

The one issue I see is that, in order to disconnect from the thrust carriage, you have to have a way to do so. The logical method is to use an electromagnet that can be powered on/off to connect/disconnect but then the car has to power that -- and that might sap it's range a bit.


A pilot line using similar technology was built in 1983 in Porto Alegre, south of Brazil (I used to live there). It was deactivated shortly after, but the elevated track still exists [1]. A new 600m stretch was built in 2013 at the airport using updated technology and still runs today.

The same company also installed a line in Jakarta, Indonesia which has been in operation for 28 years.

https://en.wikipedia.org/wiki/Atmospheric_railway#Aeromovel

[1] https://www.flickr.com/photos/ruriak/3270276680/in/photolist... [2] more pictures including the new one: https://www.flickr.com/search/?text=aeromovel%20porto%20aleg...


This YouTube video gives a pretty good overview of Jakarta's Aeromovel: https://www.youtube.com/watch?v=GM2Zxn7ybNQ. It's pretty primitive compared to VECTORR, but it is still operational (it just runs in a theme park, though).

When they ask 'why has it not been this way" isn't the obvious answer 1) Infrastructure cost. Building this vs tracks on the ground would be a significantly higher investment. And 2) if something goes wrong with the engine, the entire line is shut down, vs pushing a train off the track and other trains continuing.

And I missing something but aside form the gradient capability I didn't see much advantage presented here. And if you are going to build these atmospheric pipes why not put the carriages inside them? I wonder if you could combine the 2. Have express trains shooting through the pipes and local/scenic trains riding that energy on-top. Workable or not, great to see people developing ideas!


> if you are going to build these atmospheric pipes why not put the carriages inside them

Because when the vacuum breaks then people die if they are inside. This happens to be one of the biggest weaknesses of Hyperloop. It's not a good system when a failure _anywhere_ in the pipes causes a massive loss of life. If this guy's propulsion fails then, well, the train stops gradually, not a biggie. If air enters into a vacuum tube where the Hyperloop carriage is, the shockwave will do something to the carriage people ride in and it won't be pretty.


>If air enters into a vacuum tube where the Hyperloop carriage is, the shockwave will do something to the carriage people ride in

This is Thunderf00t's "shock wave" argument, and it has survived frequent debunkings. Are we really so easily misled that slapping sciencey branding behind any poorly thought out claim will cause people to repeat it as truth?

The huge thing he forgot is... pipes are not lossless! A tube break would initially cause the air to rush in at the speed of sound, but after a few kilometers the backpressure from friction with the tube walls will slow the air to highway speed and spread out the pressure rise. The way it works out, if you're close enough to the breach to be killed by the pressure wave, you're close enough that you can't stop in time before derailing.


> The way it works out, if you're close enough to the breach to be killed by the pressure wave, you're close enough that you can't stop in time before derailing.

Huh? Who's derailing here? The problem is, again, that if just a seal breaks close enough to a carriage, you are dead. This is not comparable to a derailing which requires quite a bit of things go wrong on a normal train or the propulsion dying in this elderly chap's magnetic train.


I think he meant in comparison to a train track breaking up with a high-speed train on it. Read the sentence more carefully as a comparison against existing train technology.

Really? How? Couldn't the train stop if the pressure starts to go up too high? It sounds a bit like saying, a broken rail _anywhere_ in a train network causes a derailment and massive loss of life. Train drivers can't see broken tracks until it's too late to stop.

1. Pressure.

2. Speed. 1600 km/s is pretty snappy.

Thunderf00t tends to wibble on a bit and repeat repeat himself, but he does make his point.

Relevant bits start about 6m22s.

https://m.youtube.com/watch?v=Z48pSwiDLIM

Or at 10m28s in this video:

https://m.youtube.com/watch?v=RNFesa01llk


> 2. Speed. 1600 km/s is pretty snappy

Way too snappy. Surely you meant /h not /s


Wups, yes. My error.

I'm sorry isn't this the guy that has a creepy obsession with Anita Sarkessian and that associates with ~Nazis~ anti-semitic misogynistic racists.

He definitely has commented on Sarkeesian, and critiques some elements of feminism, a few of whom richly deserve it. That's not an area I'm particularly interested in, and I've not followed his videos there.

His critiques of poorly-conceived technological concepts, in particular the "Solar Freakin' Roadways" scam, and Hyperloop, strike me as largely on-mark (if repetitious and self-rightous).

I'm not familiar with any Nazi or other associations, though that would be most unfortunate.

RationalWiki addresses some of this:

http://rationalwiki.org/wiki/Thunderf00t

It has no bearing on the technical criticisms addressed above, however.


His comments on Anita Sarkeesian are creepy and obsessive. Let alone the fact he blatantly and deceptively edits her videos to make his point. https://www.youtube.com/watch?v=7bVqfQvXP2o .

If he's dishonest (not that he's wrong, but that he's dishonest) about basic social studies why should I trust his science? Let alone his experimental results? To be fair he recently disassociated himself from the alt-right ("not") nazis. So there is that at least.


> ...if something goes wrong with the engine, the entire line is shut down, vs pushing a train off the track and other trains continuing.

The train is propelled by being magnetically coupled to a shuttle running underneath it. You could have more than one such shuttle; and the shuttles wouldn't have to run the whole length of the trip (potentially hundreds of kilometers in Germany, for example). There could be a new engine every few kilometers, with a backup. These engine units would be easy to replace; even easier than trying push a train off the track (which is not easy).

> ...if you are going to build these atmospheric pipes why not put the carriages inside them?

The pipe has to be much bigger to do that, and the pipe has to have an airlock to let people in and out of the train car. The airlock especially is apt to be a source of maintenance problems and safety incidents.


There are certainly operational issues around centralized power vs decentralized engines attached to the train itself. If successful, the additional construction cost could easily balance the fuel cost of moving engines around with each train, and maybe additional maintenance required for a moving engine vs a stationary engine. It's probably worth comparing to electrified rail service, which shares the benefit of not shipping fuel with passengers.

In addition to all the safety constraints mentioned, it's just simpler to build a 12-inch diameter vacuum pipe than a 12-foot diameter pipe. It might be possible to constrain the rolling stock on a line so it all clears the pipe, with some trains propelled by the vacuum pipe, and others propelled by an attached locomotive (such as maintenance vehicles, or conventional trains when the vacuum system is under maintenance, etc)


Isn't the initial track-laying cost the #1 obstacle to rail transport? IIRC it takes decades at least to break even with normal profits. I can't see any new train technology being successful unless it either fixes that problem or does something really impressive (e.g. supersonic speeds a la Hyperloop).

Decades to break even means like 5% ROI. Given how nobody seems to know where to stuff money these days (especially pension funds), the main concern is increasing the probability of success (i.e. make the risk profile match the returns).

> pushing a train off the track

How do you mean? You can push failed trains along the track with another locomotive, or you can crane them off (if you can get a crane nearby!), but you can't just push them to the side?


Its worth pointing out that for aerodynamic reasons it might take over 10000 HP to push a train at 300 MPH but if you just want to get it out of the way a farm tractor could easily push a train at perhaps 10 MPH. Even if you only go up a hill at 2 MPH its still faster than sitting there.

There's no physical connection with the piston in the pipe, just a big magnetic field. Without air pressure differential to make an air-bearing the friction between the magnet and the pipe wall might make it impossible to drag the train along. In a way, having a built in emergency brake might not be that much of a bug...

Another difference between humans and bulk cargo WRT transport systems is humans will self unload and self load into slower and less ecological and less efficient more expensive transport when and if necessary. Surely in the event of a breakdown a fleet of smokey diesel charter buses and taxis would appear to transport the people. On the other hand, the railroad has a real problem if a thousand tons of coal cars breaks down in the middle of a route, that coal isn't going to walk itself into an adjacent pickup truck or something.


> There's no physical connection with the piston in the pipe, just a big magnetic field. Without air pressure differential to make an air-bearing the friction between the magnet and the pipe wall might make it impossible to drag the train along. In a way, having a built in emergency brake might not be that much of a bug...

I'm not sure I follow. There has to be some way to start moving from a dead stop, so the plug will probably already have some kind of wheels or bearings to allow it to get moving until there's enough velocity to make the air-bearing work.


In my experience single line routes that terminate always have short passing lanes (terminology?) so that trains heading in opposite directions can get passed each other.

You'd only need to move the disabled carriage / section to one of those to enable at least some capacity for the line to continue operating.

That was my interpretation of the comment.


. . . short passing lanes (terminology?) . . .

I believe "siding" is the word you are looking for.


> I missing something but aside form the gradient capability I didn't see much advantage presented here.

* You can re-use existing carriages without having to seal them hermetically.

* You don't have to build a sealed tube for humans: No emergency exits every mile or so, no airlocks at stations except for maintenance access.

* Because the system seems to be just as wide as the tracks, existing tracks could step-by-step be retrofitted.

* Give the construction crew a few extra bucks to put some fibres in there ;)


> Give the construction crew a few extra bucks to put some fibres in there ;)

Isn't that what has already been done (at least in North America?) Weren't most fiber lines run in existing railway right-of-ways?


> * Give the construction crew a few extra bucks to put some fibres in there ;)

I don't you want your fibre getting smashed by magnets all day :P


There is a lot of fiber running in railroad right of way.

Southern Pacific Railroad Internal Network Telecommunications, or SPRINT. The telecommunications name survives. The railroad is now part of Union Pacific.

I suspect that the folks putting fiber in railroad right of way know how to avoid crushing failure.


How is an _optical fiber_ affected by _magnets_ ?

When it gets crushed by the passing bolts of magnets which consume the entire tube diameter because they are propelled by air and need to fill the entire tube in order to work.

If you want to run fibre along, and it's a good idea while you're digging away, do it in a parallel but separate tube.


I think that was the idea of the parent comment, just put anything else in the hole in the ground. Fiber is welcome :)

The article doesn't do a great job of actually explaining how the system works. If it's just this high pressure pipe with a carriage in it, then wouldn't you be able to retrofit existing rail lines? Regardless, another advantage is the centralization of the energy source.

Since the train has no motors, a lot of weight can be saved.

Reduced noise was another advantage as well as potential for powering with solar.

Good point about it breaking down.


There's a working modern atmospheric railway, from Aeromovel, with two installations.[1] It's a reasonable low-speed system, but hasn't sold elsewhere.

[1] https://www.youtube.com/watch?v=GM2Zxn7ybNQ


What is the advantage of this over a classic electric train? Weight of the locomotive? I think it is more than compensated by the ease of having more than one train on a line at a given time.

An electric cable seems way easier to maintain (and repair) than an atmospheric sealed tube.

And this has absolutely no relation with hyperloop, that solves a completely different problem (air drag at high speed)


> more than one train on a line at a given time.

Seems like the system is capable running different trains in different sections; the pressure/vacuum system is distributed and segmented down the length of the line.


One of the few existing projects that used a similar concept have..

> a ratio of payload to dead-weight of about 1:1, which is up to three times better than conventional alternatives.

https://en.wikipedia.org/wiki/Atmospheric_railway#Aeromovel


Cool idea. The main drawback is that the train still has to push the air in front of it so it's no better than a regular train. I think this is the main advantage of hyperloop. Air drag is significant over 40km/h.

I don't understand how you could have many trains on the same track. If one train needs to stop then do they all stop?

I guess you could have sections every half mile or so but that sounds crazy expensive. Putting a pump out in the middle of nowhere.

And how would train yards work? Assuming you used sections how long would they be? 10 feet?

Cool idea though, first time I've seen it.


In train yards you could probably use electric motorized carriages pretty easily, that could be switched to different lines (at slower speeds).

I like trains. Because of different reasons, Europe and China is better suited for trains (e.g. public transport in cities available).

What I would like to see: 1. An inter European Rail network. Possible 4 Tracks (freight and personal.

2. This trains should be able to connect and disconnect wagons automatically. Hence a fast train may ride from Lisbon , 3 wagons get disconnected outside the city in a railroad shunting yard and then continue to Madrid, the rest of the train bypasses the city and heads to the next big center.

3. See this technology widely used for the freight trains: http://www.cargobeamer.eu/

The big advantage of trains is that you can run them nuclear and with Thorium reactors in the future.


(2) already happens, even if it's not automatic. The train that leaves Lisbon gets divided into two when it arrives in Medina del Campo; one part goes to Madrid, the other to Hendaye (France), where it connects up to the TGV.

I know. I have experienced it. But I have experienced it as an very time consuming process. I don't see why this can't be done in an automated way, taking minutes. Not hours.

Hours? Even back with locomotive-pulled trains where you actually had to shunt the cars to a different platform that should be below 15 minutes, and today, it adds less than three minutes to the train that is longer at the platform (Ohlsdorf, Hamburg rapid transit).

Provided that both trains arrive on time.

And doing in in flight is much harder (and not legally possible), but if you would want to join/separate in the outskirts to get one into town and the other on the bypass, just the stopping and reaccelerating will cost some minutes.


It can be done very quickly with multiple units (powered carriages without a separate locomotive).

In the UK this is known as "portion working" and is a routine part of some routes' timetables.

The slight difficulty doesn't come from the separation, which is easy - open the automatic coupling, drive away the front bit and then drive away the rear bit after the front has got clear - but the joining. With an intensive timetable, waiting for a (possibly slightly late) other portion can leave a train missing its booked slot into London, with knock-on delays.


2. was done in britain a long time ago. They just uncoupled cars at the rear end and braked them down to intermediate stops; the rest of the train continues. (Ok, no bypass.)

Unfortunately the inverse operation isn't as easy, and it's an expensive operation, too.


One of the earliest working applications of this in the 19th century was very near to where I live in Dublin: https://en.wikipedia.org/wiki/Dalkey_Atmospheric_Railway. The railway was used to carry stone from the quarry (which was a few hundred feet above sea level) to the shore a couple of kilometres away, to build what is now Dun Laoghaire harbour.

One of the small roads near where the line used to run is still called Atmospheric Road.


So this looks cool, but where's the improvement here over a current electric train car? Genuinely curious. The drag remains the same, and it's still electric.

Hmm, actually, I just thought of a big plus: you're not moving your massively heavy engines with you.


In a 200 car train, what percent of the weight is the engines? My rando guess is 10% max. Building all this for 10% ecceciency seems rough.

ICE 3 weighs 400T, it has 16 motors that probably weigh less than 2T each. Overall the motores are most likely less than 10% of the weight (ICE 3 is a very light train overall, with lots of motors, probably giving it an unfavorable motor/train weight compared to an electric locomotive-pulled freight train).

A bigger concern is the efficiency of transporting energy _to_ the train. That's one of the reasons why long distance routes use overhead electricity, because you can have higher voltage (12kv-25kv) compared to third rail (600v-1.5kv).

This is like third rail on steroids -- lots of construction near the ground, probably lots of energy losses all around.

Plus it's an unproven technology, with a single vendor. It'll be a hard sell.


There's also fuel, but I agree, that can't be much either on a typical trip. And for electric trains it's zero, with comparable infrastructure requirements (overhead power lines vs ground pvc pipe).

This page as some videos showing the VECTORR scale model operating in various modes: http://www.flightrail.com/our-prototype.html.

The Wired article is devoid of media but there are a number of good videos of the Flight Rail on their website:

http://www.flightrail.com/our-prototype.html



Maybe it could be used for those kiddy trains at amusement parks.

As always the reason we do not have such ingenuity in the mainstream is that the mainstream is an industry addicted to the easy profits that is essentially big oil. Think of it what you will.



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