
Elon Musk's tunnel plan is surprisingly outdated–and bad - oftenwrong
https://www.curbed.com/2017/5/1/15500714/elon-musk-tunnel-digging-traffic-ted
======
netinstructions
> He does say he’s working on developing a TBM that simultaneously digs and
> reinforces tunnels, one of the big engineering challenges for tunneling.
> Musk should have given his TED Talk on that instead of this surprisingly
> archaic idea for addressing vehicular congestion.

I too have more hopes that this could "dramatically change the way we build
and finance infrastructure" than all the other aspects of Musk's electric
sleds for cars and the associated elevators that go with them to ferry cars
around underground.

However, a TED talk on TBMs is a boring, unrelatable talk. A TED talk on how
we can "drive" our cars around awful traffic is something many, many Americans
can get excited about. Even if I agree with the article author that the
assumption that cars are the de facto way to get around is misguided and
wrong.

In other words, let's appeal to the affluent car-centric/politicians/lobbyists
in cars so we can get better TBMs for public transportation projects down the
road that those demographics don't usually support anyways.

~~~
Gravityloss
Maybe another route to nicer cities is this: you put the cars and buses
underground while pedestrians, cyclists and tram riders can enjoy the pleasant
views and sunshine.

------
Obi_Juan_Kenobi
It's bad because it's not public transportation? Is that really an argument?

The idea is clearly that tunnels allow you to scale along the z-axis, and thus
facilitate density. Whether that's car-sleds or small trains or something
else, that's not really the point.

This also shows a lack of imagination with regard to public transit; yes it's
very efficient in some ways, but door-to-door transport is very desirable as
well. With the development of small electric vehicles and autonomous driving,
a hybrid mode of transport becomes possible; small vehicles can come together
in 'trains' or along special corridors that still permit door-to-door service.

There are plenty of good criticisms for Musk's various projects, but griping
about a fun video is disappointing.

------
undersuit
>What Musk’s video doesn’t show is the gridlock created when all these
vehicles try to “merge” down into the subterranean highway at the same time.
It’s no different than an above-ground highway. At all.

But it is!

The sleds are all equally performant, that changes traffic flows considerably.

The sleds are all networked, merging on roads is difficult because of lack of
information and coordination.

When controlling the sleds in one of these tunnels and a new vehicle is going
to be inserted into the flow of the existing sleds you have many options. You
could slow down all the incoming sleds, insert the new sled in front of the
slowed sleds, and then speed them all back up at a controlled synchronized
rate. You could have the new sled just wait until there is a time to enter the
tunnel and accelerate to the correct speed. You could speed up some sleds and
slow down others to make a hole in the flow for the new sled.

But it's not merging like we know now. Cars all have different properties that
make them different and the drivers are different too. Of course merging is a
pain when undersuit's aging truck is driven up the on ramp and it has to
accelerate from 25 to 45 to 65mph... onto a road way where people are driving
from 50mph to 80mph.

------
unstatusthequo
Make a better one if you don't like it and quit bitching about someone who has
the balls to try and make a difference. Who are these armchair assholes who
contribute nothing and have the audacity to complain about it? That mentality
is exactly what's wrong with this country.

------
surak
The author misses the point completly, everything Musk does starts with an
implication analysis of what is needed on Mars. If he can generate some cash
here on earth for covering development costs, it helps the grand project.

~~~
woodandsteel
Hey, that makes sense, Musk will need lots of cheap tunnels on Mars.

------
randyrand
Induced traffic is the reason country roads always have bumper to bumper
traffic. Oh wait...

