Elon Musk Unveils Boring Co's First Tunnel
latimes.com
latimes.com
LA Times version says: "Not available in your region"
Umm, and the capacity of these tunnels is also orders of magnitude lower than a subway. It would also be a lot harder to use and available to far fewer people. This entire idea should be laughed out of existence, but despite everything, Musk still gets fawning coverage for any crazy idea he spouts.
Maintenance will be impossible. Breakdowns of any sort would go from being annoyances to a few to being catastrophic failures for the system. Even if the tunnels never degraded, even if no car ever had a flat tire in the middle of the tunnel, and even if you could actually achieve 150mph (which would be extremely unpleasant for the passengers anyway), you couldn't physically fit enough cars through the tunnel to compare to real transit system. Given that this thing requires rigging something up to your vehicle, the onload and offload points would immediately become major bottlenecks to any serious throughput even if you could cram them in bumper to bumper.
How so? Maintenance happens all the times in subways. In Montreal they do it during 4 hours each nights. In ours, they close everything down, thus we can no longer use it, but if we had multiple smaller one, we certainly could close one at a time and lower the perturbation. They could still close them all, theses tunnels aren't meant to be the only ways to drive either, even the biggest highways are closed from time to time to maintains them.
> you couldn't physically fit enough cars through the tunnel to compare to real transit system
That's seriously so weird to see that kind of comment on Hacker News. Never heard of horizontal scaling? There's more than a ways to increase capacity and the size of the unit sure is one, but the number of units is another one. It's like saying Google is impossible because you could never fit that many website on a single core, yeah luckily we can just add cores.
> Given that this thing requires rigging something up to your vehicle, the onload and offload points would immediately become major bottlenecks to any serious throughput even if you could cram them in bumper to bumper.
Then they'll come back to the skate system, which would fix the tire issue at the same time (and many others).
My SO is a soils engineer/geo-physicist, so I know a bit about the issues at play, mostly over dinner conversations. When it comes to large infrastructure projects like these, the problems are multitude and all very individual, especially in such a geologically active zone as the LA Basin [0]. Though Musk et al. should be congratulated for the incredible achievement of even trying to pursue this idea, proper study is always required. Honestly, I've no idea about the studies that they have undertaken. But in such a place like the LA basin, I'd imagine that they have taken such measures; it would be insane to do so otherwise.
When it comes to horizontal scaling, without a proper geologic survey of the bedrock, water table, oil-wells, soil dynamics, and all the many other factors, simply multiplying the structures on top of each other can only be described as a deliberate attempt to endanger the lives of all people concerned (riders, construction crew, etc). The surveys must be made with deep consideration and respect to the laws of physics and the local environment. Brady, of Practical Engineering on YouTube has a wonderful channel that goes into some depth about large scale civil engineering [1] that is well worth a binge.
That said, with proper study of the effects and dynamics of increased removal of soil and bedrock, horizontal scaling is of course a perfectly good solution to increasing ridership.
what's this? PhD by association?
I came to Bay Area from Japan, I was surprised to hear that high buildings are not a thing here because of earthquakes. For comparison, in Japan there are about 2000 earthquakes that person can feel every year. And somehow monorail/high-speed trains/tunnels/skyscrapers are everywhere. Lazy engineering and crumbling infrastructure which stayed same for decades.
>what's this? PhD by association?
I mean, I did day that I only know a bit about it.
That said, there are differences in the dynamics of the soil between Japan and California; each situation is unique. When it comes to earthquakes, Japan typically has deeper earthquakes due to the subduction zone that it sits above and the earthquakes are compressional(very roughly), while in CA, the earthquakes tend to be shallower along the San Andreas and more strike-slip (again, very roughly) up to 30km down involving mostly the crust. In general, one should not expect that buildings in two different seismic zones should be similar.
> can only be described as a deliberate attempt to endanger the lives of all people concerned
I can’t fathom how one statement follows the other.
Even assuming that capacity/dollar is actually worse than subways, they can still be economically superior, for the same reason solar+battery is beating nuclear. The ability to incrementally build capacity relatively quickly and with relatively low, incremental costs beats any system that requires billions of initial investment and only comes online in the timescale of decades.
And I really don't think that capacity/dollar will be worse than subways, assuming that he intends to build off-ramps for leaving the system, as alluded to in the stream. Simply removing the need to stop at every exit greatly improves capacity, and while the capacity of an individual tunnel is still much worse than a single subway tunnel, they can just build more.
> Maintenance will be impossible. Breakdowns of any sort would go from being annoyances to a few to being catastrophic failures for the system. Even if the tunnels never degraded, even if no car ever had a flat tire in the middle of the tunnel, and even if you could actually achieve 150mph (which would be extremely unpleasant for the passengers anyway), you couldn't physically fit enough cars through the tunnel to compare to real transit system.
You seem to be assuming a single tunnel per direction. Assume 20 instead. Suddenly a car failing in the tunnel turns from a catastrophic failure into one that causes some traffic to have to take a little extra time as they back their way to the closest cross-tunnel, and a relatively minor loss of capacity until a recovery vehicle can come pull the broken one out.
And as Musk said like a dozen times in the stream, he intends to match a real transit system not by increasing capacity per tunnel, but by starting building tunnels and then not stopping until there are no more traffic issues. Since he gets to expand in three dimensions, he can just stack them on top of each other.
> Given that this thing requires rigging something up to your vehicle, the onload and offload points would immediately become major bottlenecks to any serious throughput even if you could cram them in bumper to bumper.
Their demo had the "subway wheels" deploy automatically, while in the elevator. For high-throughput exits, they probably need to bite the bullet and just build off-ramps.
I think this is the really important part. Think of it like a computer bus - do you want a single channel able to move a lot of data at once but with potential bottlenecks as various systems fight to talk to each other, or lots of channels able to move medium amounts of data without bottlenecking one component while favouring another?
When one channel is at capacity you move to the next, with further redundancy to spare.
But all this discussion of what to put in the tunnel seems very silly to me. Are they just re-discovering subways? Do they know that there are subways in the world (e.g. Paris) that run out rubber tires?
Also note that if you get an increased amount of people commuting in these tunnels without their own cars, new public transportation built by the city becomes a lot more valuable as well, since there's already a lot of people getting around without cars.
That said it is funny how private companies seem to rediscover public transport. Looking forward to Uber Train.
For example, expanding subway systems is currently in the hands of very badly run semi government institutions who are arguably quite bad at even utilizing the tunnels they have. E.g. the new york subway system is famously less efficient than ever due to the fact that they keep reducing the speed at which trains travel through it. Digging new tunnels is relatively rare for them; and when they do dig new tunnels, they tend to just use them exactly the same way as their existing tunnels, which is not very efficiently. Also, like most government infrastructure projects, progress is slow and things tend to go way over budget.
Musk's approach is twofold: 1) turn tunnel digging into a scaleable business. 2) provide concrete things to do with these tunnels that are not backwards and stupid that he can sell. For example, if you have autonomous vehicles, you don't need a lot of expensive infrastructure inside the tunnels to get from A to B. Infrastructure like rails, signaling equipment, power lines for the trains, etc. It so happens he has a business for autonomous vehicles already. He sells the whole package. That's why he's emphasizing the use cases.
This is classic Musk, he thinks end to end an he might actually pull it off.
Things always are wonderful when they're research projects that don't need to conform to real-world limitations.
My point here is that there's still a lot of room for improvement, even if you limit yourself to trains. It doesn't seem like such a stretch to extend it a bit further to this new emerging system.
His first argument is that it's currently too expensive to have any innovation. This tunnel cost 10 millions $. Sure it's usage is still hypothetical, but you can't say this won't be much more accessible to innovate.
I'm in Montreal, our subway barely changed in the past 30 years. I was lucky, I was affected by one of the only change they did in theses 30 years, 3 more stations on an already completely full line. That came with a 745m$ price for 3 stations that sure allowed people further to take it, but it didn't increase at all the actual capacity. It's hard for any of our administration to even consider any major expansion because of that.
If making smaller projects now make sense, maybe we will see more innovation in the technology, in how they are handled, etc...
Montreal's metro throughput is not gated by the tunnel capacity. It is gated by the amount of trains in operation. Adding additional cars on the 'already full line' would increase the line's capacity. Neither the orange nor the green line are close to full.
The issue with the orange line extension isn't that the lines are full. It's that 1) subway costs are heavily subsidized at the municipal and provicial level, 2) they were extended to Laval which funds the STL, not the STM, and 3) there was no revenue or cost sharing agreement between Laval and Montreal to subsidize the STM in proportion to the burden placed on the STM by Laval riders.
This issue with cross-subsidization also lies at the core of the municipal agglomeration which occurred in Quebec metropolitan regions.
Montreal won't consider additional subway expansion not because of financial and infrastructure cost reasons, but because of political ones, much in the same way that internal negotiations regarding the dual super-hospital projects were intentionally sabotaged for political reasons.
China is indeed digging at huge speed.
My understanding with the Boring company is not that they are doing anything particularly special but merely doing things in a way that facilitates economies of scale. So, they standardize designs, equipment, logistics, etc. and they use automation. If you do a one off tunnel with a machine that will only be used for that tunnel, that doesn't make sense. If you are planning to do many tunnels that makes a lot of sense.
2 lanes of 3 rails that are grade leveled should be relatively less expensive than paved, with rebar grade leveled; especially over time, with the increased wear that liquid has.
Electric trains are considered quite safe yet tunnels have a lot of escape paths and service tunnels built parallel to the main one.
This looks the size of a emergency tunnel. Still, the cost of building it seems pretty low. Boring Co could build two side by side, (one for each direction) and have emergency hatches between them.
As safe as any cave open to the public, which there are many of in state and federal parks often with only 1 or 2 exits.
Also, barring an act of terrorism, it's probably as safe as driving a car, safer than skiing (water or snow), exponentially safer than sky-diving etc.
>What happens if there is a fire and you are in the sixth tube down?
Compared to the feat of actually tunneling the machine, boring small escape tubes would be relatively trivial. Employ magnetic-electric security doors that can be remotely released or unlock in the event of a power failure and anyone able bodied could climb a ladder out, make them wide enough to get a rescue harness down and fabricate in an anchor point for a safety line and anyone not capable could be lifted out not unlike how rescue helicopters lift people with a winch. And really, the operator could install the harnesses and winches too and have them be both electric with a way to easily connect them to an external power source and/or manual for redundancy. All you'd have to do is test them once or twice a year and lubricate as necessary.
I'm pretty risk-averse but I wouldn't hesitate to use one, even without escape shafts.
Actually, really, laughed out loud.
https://twitter.com/Model_4_/status/1075270290978963458?s=19
Note that air resistance is a much bigger problem in a cheap, narrow tunnel.
Challenge with Elon's tunnel is you're stuck underground with no escape options, and maybe nowhere for the smoke to go
As well as escape options most tunnels in EU, also have smoke extraction, fresh air insertion options which help make it easier for passengers to evacuate.
Tunnel fires (even miles from anywhere) are survivable with the right design - https://en.wikipedia.org/wiki/1996_Channel_Tunnel_fire
High speed automotive tires are expensive because they need to withstand all the flexing that comes from running at high speed with the kind of inflation pressures that deliver what the owners of the high dollar cars they go on consider a reasonable ride. They have to be fairly soft/flexible tires for the same reason. A hard, stiff tire would not deliver the kind of traction people expect from a German driving machine.
Basically you have speed, weight capacity and ride quality and you only get to pick two. So long as you can compromise somewhere everything is easy and cheap. A boring old light truck tire will live a long life at 150mph so long as you run it at a very high pressure and light load.
If you want to see this principal in action look at small trailer tires (like snowmobile and jet ski trailers). They carry a ton of weight (for their size) and run at very high speeds (a sub 20" tire is really spinning fast at highway speed) by running very high pressure with a stiff sidewall and the kind of rubber that makes butter look like a high friction surface.
So yeah, tires are the least of their technical issues.
I guess that depends a lot on the density of cars and topology of the tunnels (a simple loop would be ideal, I think).
I took 2 tunnels to and from the airport today. Each way, over $10. But I'm damn glad I took them because they go all the way from north of the city, to south of the city, including under the river, where our bridges are massive bottleneck.
I saved at least 30' and a lot of sanity, and this was before work. I'd be dead tired if I had to deal with traffic jams for 45'.
Heck I'd even chose a bumpy tunnel over the surface.
Buying a competitors device is a really smart move as a first step, since much of the low hanging fruit gains are in the activities around the machine to save that 4/5s of time when it’s idle. As a startup it’s almost always best to bootstrap with the competition’s product if you can, makes rate of learning so much faster.
Was certainly how the CrossRail and Channel tunnel machines worked
See diagram on https://www.bbc.co.uk/news/uk-17365934
Musk keeps showing this comparatively tiny machine, whereas in reality they're 150m long
- internet payment platform, check
- first privately founded company to do orbital launch, check
- reusable cheap rockets, check
- biggest rocket available + it's reusable, check
- Dragon spacecraft, check
- crew spacecraft, check (still needs testing, starting early next year)
- Model S, check
- Model X, check
- Model 3, check (work in progress on 35 000$ version)
- Boring Tunnel, check (work in progress on scaling up)
- Starlink, check (test satellites are flying over your head, work in progress on full deploy)
- Big Falcon Rocket, work in progress
People emotions simply get the better of them in situation that are so public, every little detail gets blown out of proportion in either direction.
The plain fact that he controls and builds multiple US based billion dollar companies seems to get lots AT THE VERY MOMENT when US based manufacturing has been on of the prime political debates is astonishing for me as an outsider.
I suspect one of the reasons journalists are so unfairly critical of him is that the story keeps changing. As an engineer I know this is because he is adapting to circumstance and the reality is that we ought be thankful that he is showing us early glimpses at all. But a journalist looks at that and says "wtf? if I report on this then it's my credibility on the line when next year it's morphed into something else."
Musk is interesting in the first place because he is not a typical boring CEO. So they want to use him as clickbait, but then they get shitty if its not 'polished' like what they get sent from the PR departments of other companies.
To be fair, if you gave me ~$6bn from the Government, I could probably have a bloody good go at it too.
> - internet payment platform, check
Sure, he created x.com but who ever heard of that?
Other things:
Battery swap - https://www.tesla.com/videos/battery-swap-event (interestingly, NIO in China has this approach working).
Coast to coast autonomous drive by 2018: https://futurism.com/elon-musk-teslas-autonomous-car-will-dr...
FSD (Full Self Driving) option in general is looking like vaporware. I'm wondering if Tesla is going to need to refund the money people paid for that option. It's no longer offered.
Here's the latest promise, about Summon mode with Tesla: https://twitter.com/elonmusk/status/1057871356367269888
It was promised for ~6 weeks, ~6 weeks ago. So that should be out any day now, right?
He was also going to fix Flint's drinking water. To his credit, he recently made a charitable donation instead, but it was originally phrased as engineering help.
https://www.theguardian.com/us-news/2018/jul/12/elon-musk-fl...
And of course there's the whole Thai cave torpedo thing which was just... weird.
Edit: oh can't believe I forgot the solar roof. That one is perhaps the closest to outright fraud, since it was unveiled on a Hollywood set with FAKE shingles! https://mansionengineer.com/2018/08/10/elon-musk-tesla-and-t...
I get that we want people like Musk to push boundaries, but I think it's a fine line between what Musk does versus The Simpsons monorail guy.
https://twitter.com/elonmusk/status/999374720368689153
Earlier this year, the media put out hit piece after hit piece on musk after musk criticized them. Seems like years ago though.
See all the negative comments in this thread, for example.
Instead saying "Jeez, this looks interesting. I'm happy some billionaire is trying to fix the horrible traffic problem instead of just buying more McMansions and yatchs. It seems complicated and I'm not sure it will work because of reason x, y and z, but it will be cool to watch!"
The collective American voice is now: "Stupid! Will never work! Waste of time!". (And angrily at that)
It's a real shame, because people who genuinely try to make life better for others are rare, and America needs all of them they can get!
5/95?
1/99?
Watching science newsreels from the 40s-60s you notice that they're the epitome of boundless optimism.
Automation allows for all sorts of new options in vehicles. This is a platform and many services can sit atop it. No reason why people can’t develop a carpooling service for 6-12 person vans and run those on this. Or services that travel to clients rather than visa versa.
Also, and very important to the cost argument, is that system cost is offset by individuals and external services purchasing fleets. This makes it a lot more practical a transit option to build than typical public transit or freeway fixes which require multi-year, multi-billion dollar outlays and consequent decision making apparatus. Consider what properties an ideal transit option has:
a) easy to add very incremental capacity (vs big long projects)
b) doesn’t have to deal with right of way
c) shares costs with private market & individuals
d) can reach any location point-to-point
e) offers broad access to citizens
Seems this + autonomous fleets serving different market segments and needs has these properties. If it works.
Also not everyone can afford a luxury car.
Just imagine lyft, lyft line, and a bigger lyft line. They can all coexist.
Ok fine. Why would I take a van if I can take my own car, period?
And ideally these systems mean less cars on the road / less car ownership, with higher utilization (cars sit idle 96% of the time, they’re the worlds most underutilized asset)
So here's an idea - how about they run subway trains in these tunnels instead like they do in the rest of the world?
So here's an idea, why is there no subway trains there? Easy answers, not enough money/value into them.
He suggest a way to add value to the system, by allowing luxury cars to go through them and save traffic time. It's also a way to keep your car before and after the path, which can't happen in a subway. Theses add values.
Smaller tunnels can also be much more cost effective and can be done in an iterative way, based on the actual needs of the system. In Montreal (my city) that's a big issue where we just can't get the funds to improve our subway system because it's just so much money which is hard to justify. Our government pension program is currently funding a pretty big improvement in our transit system because THEY have the funds to do it and it's going to be profitable to them. They made it profitable to invest into our infrastructure and yet the freaking government can't do it.
So basically this only works with Tesla vehicles at the moment. I'm wondering how that's going to expand in the future--if at all.
Do they have a standard which other vehicle manufacturers are expected to include in their car designs to be compatible with these tunnels?
This is making me question the viability of it, because without buy-in from manufacturers, it seems seriously unlikely that any government is going to approve a sprawling Tesla Guide Wheel Tunnel™ network.
Makes sense to add these to the vehicles so the tunnel can be as ‘dumb’ as possible, since we’ll need a lot of tunnels to make a dent in traffic.
Note also Tesla’s prior commitment to opening their patent portfolio for OEMs to use. Seems similar approach (platform play).
But then my original question remains: why do they need guide wheels for this, when they can do 90 mph without them on normal roads?
The tunnel in the article is very narrow. Imagine trying to drive at 90mph through a car wash without touching the sides.
I can see some interesting failure modes where the wheels fold up in normal driving. Yeh I know its not supposed to happen but one Uk maker had steering wheels that could come off whilst driving - this was used in my mech eng course as a cautionary example.
Steering wheels come off in MANY race cars, IndyCar it's basically a necessity so you can get in and out of the cockpit.
In the case you mention it just sounds like design incompetence.
So the o-Bahn Busways in Aus, just underground....
What if we use special cars only for the tunnel with some kind of ride sharing system? and then we put the cars on rails? This keeps them on track and also the rolling friction is much lower.
Also, we could continuously charge the battery of the car if we have some kind of wire going alongside the tunnel and a slip contact.
Actually we could make the cars much bigger as well, so they can hold more people.
Get me patent lawyer.
Also, the skate was supposed to provide the automation. How does <random EV> autonomously navigate the tunnel network?
Then inside it looks like a safety and escape hazard nightmare. What happens when someone gets a flat tire?
Flat tire seems easy, probably a limp home mode to nearest exit + slow down nearby fleet. There should be many exits and relatively close to each other since they’re so low cost.
I’m more concerned about fire & earthquake.
Maybe it’d just be a big thud and the car goes into limp mode. Worth modeling and having risk assessment on either way.
As to the notion that there's lithium metal in the batteries that could react with the water, you're thinking of non-rechargeable lithium batteries. Lithium ion cells use a lithium compound, not just pure elemental lithium. The formulation might be something like LiFePO4 but the point here is that it's not just lithium metal sitting around inside of it.
Also Tesla has an emergency response guide that includes instructions on fighting a battery fire. It's on page 22 (23 of the PDF) and it makes it clear that you want to douse the thing in as much water as possible and keep dousing it until it's totally gone. Tons of water is exactly what's called for when fighting these kind of fires.
https://www.tesla.com/sites/default/files/downloads/2016_Mod...
You can whizz a car along at 150mph but sooner or later its's got to leave the tunnel, the external traffic will undoubtedly be flowing more slowly so ultimately traffic is going to backup in to the tunnel
Chicago has got an elevated train [0] and even double decker streets [1] and those don't have lots of the problems that tunnels do like ventilation, escape tunnels, and moving all the dirt.
There might already be a standard of some kind that could be used either directly or as a sub-multiple the same way that European kitchen fitments are generally 600 mm wide modules.
There is nothing magical about units of measurement, neither SI nor what Americans persist in calling Imperial (when they mean US Customary or even worse US Survey Foot).
https://twitter.com/elonmusk/status/1075230308545454080
How can this man honestly think this sort of system could be higher capacity than a subway?
The point is to make tunnel boring cheap and to build an system of dynamic individual or group transport.
Rejecting the system because rich people use it first is socialist logic and has no place specially if its not done with government money.
Lowering cost is Elon’s demonstrated strength (SpaceX rockets and Tesla batteries), so gotta factor that in. Small tunnels cost way less than subway tunnels, not factoring in improvements in boring ops. It’s all about shaving off 2x here and 5x there across the whole system to make it cheap enough to get benefits.
Lower cost let’s you open up new routes to lower density areas. Means cars can get off the road from those areas which would otherwise contribute to traffic.
This is like going from mainframes to personal computers - enabled by lower cost, more people can have access.
LA metro has a tough job in their hands with handling their traffic and is likely behind this. It’s not trying to be or marketed as a direct substitution for subway, it’s another option that happens to compare favorably but be implemented in a different way and by different parties.
Alternative comparison is to freeway which has 1 car every 2 seconds, and this claims 1 car a second on main path.
There are lots of constraints building underground. Because on ground level the buildings have been built with certain assumptions about the ground regarding the construction structure. When the underground now changes, then either the ground will collapse or the underground tunnels have to been build statically according to those requirements. That is the hard work of tunneling.
Also maintaining the tunnels regarding ground water levels is hard. Changing ground water levels also has impact in the statics of the building on the ground.
There are much more things to consider building and maintaining underground.
Trying new ideas isn't a waste of everyone's time, it's research.
it might not even need regular rails. there are trains that work with rubber wheels (paris subway had that for decades already), so it would really just be fancy busses with guide-rails.
EDIT: pretty much the same idea is mentioned by several others in this discussion, so it seems not to be to far fetched.
of course, given the popularity of public transportation in LA, it makes sense that they are going for the ability for people to use one vehicle from their home all the way to their destination. i just hope they focus on actually getting the most use out of the tunnels, even if their initial vision doesn't work out the way they intend.
vacuum tunnels would work too,
https://en.wikipedia.org/wiki/Vactrain https://en.wikipedia.org/wiki/Hyperloop
not sure if the hyperloop idea works for short distances.
Or worst case likely office, manufacturing or even residential space, I mean... that's a LOT of square footage that just got created in an area with very expensive real estate.
if we go that route, the worst case would be use as sewers.
or for wiring, or package delivery.
12ft diameter gives you at least 8ft of internal space x a mile. Japan for example has 100sqft apartments. I've worked in an office, in Indianapolis, that wasn't even 8ft across and there were 20ish of us with desks against the wall so little space you had to slide all the way in for someone to walk down the aisle.
You could cut a channel down the center for plumbing and electrical conduit, probably only have a foot of clearance on one side, then have a walkway down the other side and make quite a bit of comparable office space.
Most THOW, tiny homes on wheels, are less than 8.5 feet wide to remain legal trailer width in most states so you've already got people living like that in the US. Here you could cut elevator shafts every eighth of a mile and just make the freight elevators. Say after fire suppression, pumps etc, you only have 4500ft of length to rent/lease/sell you could have 200+ small offices/apartments/artists spaces/climate controlled storage units.
I mean a Type IXC submarine (like U-505 at the Museum of Science and Industry in Chicago) had a pressure hull beam (width) of 14ft 5in and you still had material between the crewed area and that hull. Having been in U-505, and being 6'1 300lbs, even with a full tour I found it had plenty of room to move about and would have happily lived on it. Especially if it didn't have pipes/gauges/equipment/cabinets/cots etc hanging off the walls. Those things ran with crews of 50-60 people for months at a time, small offices or flats for 1-2 people would sell quite well I'm sure. Hell, I've been in escape rooms that weren't wide enough for me to lay down in.
I'd live in the tube.
japan has small apartments out of necessity. not because they like living in small spaces.
add that working or living under artificial light is not exactly healthy. this idea strikes me as something for an emergency shelter, backup workspace, but not for normal operation/living.
Off the top of my head, here are issues train cars face with managing density that autonomous vehicles wouldn't face:
1. Needing to stop at stations where few people are getting on or off, meaning that trains behind you must be at least (MAX_SPEED * STOP_TIME) behind you. With cheap tunnel boring + AVs, you can quickly and cheaply build tunnel branches that skip exits, so individual cars need less space between them (you branch off to exit; no need for extra rails or switching technology, since it's built into the cars).
2. Entrance/exit from the train car: with trains, any jerk can run in as the doors are closing, preventing the train from leaving, backing up the trains behind you and leaving a huge gap with trains in front of you. With AVs, you're already in the car.
3. Trains have fairly long stopping distances, increasing the distance needed between trains for safe operation. Some quick Googling indicated that an 8-car passenger train traveling at 80mph can take over a mile to come to a complete stop — it's hard to imagine a car with such long braking distances. That puts a pretty hard lower bound on how densely you can pack an ordinary subway tunnel.
Maybe I'm totally wrong, but it would be more useful to give actual data and evidence than knee-jerk shutdowns. It's not obvious to me, a non-train-engineer (like many on this site!), that the dismissive tweet is particularly meaningful.
There is no universe where an SUV holding 4 people is more space efficient than a Skytrain car.
And how expensive was it to build the train? If you can build 3x the tunnels for AVs as you can train tunnels and trains for the same price, actual throughput dollar-for-dollar in infra spend would be much better with Boring Co tunnels.
Update with data: it cost $2 billion to build 50 miles of Skytrain. Apparently this prototype Boring Co tunnel cost $10 million per mile. That's a 4x cost advantage for Boring Co mile-for-mile, and I imagine they'll try to strengthen that advantage even further; after all, that's their whole company's purpose: cheap, efficient boring.
..and? A car also doesn't carry 500 people.
This plan is like when a city widens a highway but doesn't touch other parts of the road network? What happens? It just moves the choke point somewhere else in the network.
Almost all assumtions in the discussion start directly in the tunnel, and sometimes at the elevator. Almost no one thinks about: how will cars get into that thing from the road, how the cars will get out of that thing onto the road.
Factor in cost advantages of the tunnel — 4x cheaper mile-for-mile for the prototype, it seems like? — and the same dollars spent on Boring Co tunnels could actually move a lot more people than Skytrain: you can build 4x the tunnels, moving nearly 1300 people instead of 500.
Even if SUVs can only match the fastest average Skytrain line (50mph), that's still fairly competitive even at the current cost per mile of a Boring Co tunnel. Assuming they can bring cost down further (which is the goal of the company), they could still end up beating trains in terms of people moved per dollar spent.
Listen, I'm not saying it'll happen. But the dismissiveness here reminds me of the "Model 3 will never cost less to build than the price to sell it!!!!!" or "Tesla will never make more than 1000 cars per week!!!" or cash crunch or etc hysteria. I guess Elon attracts that by constantly missing deadlines, but he often still delivers; he just delivers a year or so late.
You're fond of throwing in a lot of utterly implausible figures to support your argument here
The fact is that a 500 capacity train running at 75-100s headways destroys this system capacitywise.
Musk has a long, long way to go before he shows that this idea of his is better than the 1986 era technology at the core of Vancouver's system.
This is like that linked tweet: all assertion, no data. What are you using to estimate the theoretical throughput of a Boring Co tunnel system vs Skytrain? Let's debate that. Right now it's all just thin air.
Assumptions I'm willing to believe, and thus make me interested in this prototype's viability:
1. Cars need less space in between them. 5-10s gaps seem more than reasonable based on highway driving. This seems especially true since these are operated autonomously in highly controlled environments, meaning we might need even less distance between cars than free-wheeling, human-operated highway driving.
2. Most train stops are useless for most people — maybe 3x stops per ride on average? Having only one stop per ride would dramatically improve average speed, since a smaller percentage would be spent slowing down, speeding up, or waiting at a station.
3. Smaller tunnels are cheaper to dig, meaning dollar-for-dollar you can build more of them to make up any remaining capacity difference.
And we also assume that all cars can enter and exit the system with no delays.
It'll be a miracle if it reaches bus capacity, much less train/subway capacity: https://www.thoughtco.com/passenger-capacity-of-transit-2798...
Basic geometry.
While this was demonstrated with a SUV there’s no reason why this can’t be used for a larger van carrying 6-12 people and tied to a carpool service. 12 people hurtling down this each second is pretty decent capacity, especially multiplied by many tunnels that do an even better job at getting people to the last mile.
It’s a platform, not just a Tesla-mover.
Except universes where a train doesn't pick you up at your house, drive you to the front door at work, take you to your kid's school after work, then take you to drop the kid off at karate practice, then take you directly to the grocery, then back to karate practice, then home but allowing you rapidly move your vehicle through a congested city thereby reducing surface congestion making overall travel conditions more efficient and reducing the need for car parks at public transportation stop for people that live in suburbs.
You mention "cheap tunnel boring" - maybe that is the keystone of Musk's plan that will change the paradigm... With a little knowledge of tunnel boring I fail to see how to disrupt its crazy complexity, especially in urban environments whose density extends underground already: in my neighborhood (La Défense business district) a whole new station is being build wholly under existing construction and interconnected to existing subterranean works, without any disruption - insanely good engineering and insanely expensive.
Even the Waterloo & City Line, the most unloved of all lines, manages 3.5k/hr over 260 days (16M/year, 5 day week).
If you could bore 4x the tunnels, you'd need a capacity of 4 people per car to match peak BART. And... hey, that describes pretty much every car in existence. But using the BART comparison: recent estimates [1] put each additional mile of BART track at over $1 billion. So if it really costs $10MM/mile for the Boring Co, you could bore 32x the tunnels and beat BART capacity by a factor of two assuming even single occupancy vehicles, at about a third of the cost.
[1]: https://sf.curbed.com/2018/6/18/17464616/bay-area-subway-tra...
The BART is a particularly poor example. There are _tram_ systems (ie partially-segregated rail) which do better than once every five minutes.
1. most subways don't operate at 150 MPH
2. subways stop at every stop even if the majority of passengers aren't getting on or off
3. subways can't route individuals (or small groups) directly to their destination, including via normal roads
except in new york where there are direct trains and local ones -- it's a good demonstration of why #2 is such a good idea.
Subway systems are absolutely useless unless the stations are spaced very close together and there are other means of transit from the station to where you want to go. There is no point taking the subway when you need to walk several miles from the station to your ultimate destination.
There are only a handful of cities in the United States dense enough for a useful subway plus local transit system to make sense. New York is one. Chicago is borderline. Los Angeles is far too spread out for such a system to work.
On the other hand, if I can turn my car into a subway train and then get out of the tunnel and drive to where I want to go, that's actually useful.
No they are not. Scooters and bikes are a great way to arrive at your destination sweaty, and you are at great risk of being run over by cars.
Multi-modal transportation only works if your coworkers don't care what you smell like.
I won't take public transit unless it's more convenient than driving a car. Nor will most other sane people. Even in the countries with the best public transit, nobody uses it when it is more convenient to drive. It's wonderful for dense cities and it's worthless everywhere else. By "dense" I mean London, Paris, and Tokyo. Once you get even 10 miles outside the centers of those cities you will find that driving is better, and that's what people do.
The scooters I'm talking about are electric so you won't sweat. e-bikes are also a thing and they are becoming more of a thing. Finally, I'm sorry you feel uncomfortable around people. Not everyone does and for the most part public transit smelling is a meme that doesn't square most of the time.
It works when the city has embraced it. E.g., in Sweden most workplaces have showers.
> Multi-modal transportation only works if your coworkers don't care what you smell like.
This makes sense if we're talking _today_ in cities such as LA, however if you look at biking-friendly cities such as Amsterdam or Stockholm, it's not really the case at all.
I'd go so far as to say that, in my experience, biking to work is as common (or even more?) as driving to work in central Stockholm, and the sweat problem you're talking about is really non-existing.
It's not free money. He has to give some value back.
Sooo... How is Musks' solution different? It's absolutely useless unless you have entry and exit points spaced very close together and there are means of transit from the exit point to where you want to go. You basically create chokepoints at each of those entries and exits.
https://www.google.nl/amp/s/www.latimes.com/local/lanow/la-m...