
A New York railroad uses lasers to stay on schedule - tomohawk
https://www.thedrive.com/news/31607/choo-choo-pew-pew-how-a-new-york-railroad-uses-scorching-lasers-to-stay-on-schedule
======
sandworm101
This is not new tech. Lasers have been cleaning rails in Europe for years,
mabey a decade or more. If anything, this is only new in the US. It is not
unproven tech and those involved are being disingenuous in describing it as
so.

[https://www.popularmechanics.com/technology/infrastructure/a...](https://www.popularmechanics.com/technology/infrastructure/a11649/dutch-
railways-laser-clean-train-tracks/)

2002

[https://www.laserfocusworld.com/fiber-
optics/article/1655239...](https://www.laserfocusworld.com/fiber-
optics/article/16552393/ndyag-laser-removes-leaves-from-rails)

[https://www.youtube.com/watch?v=Kh6U4QJmutA](https://www.youtube.com/watch?v=Kh6U4QJmutA)

"all thanks to pioneering laser technology that most railroads are too scared
to try out."

No. Most railroads are not scared of lasers. Those with the business case for
this tech use it. Those without do not. Maybe "most" American railroads don't
use these things but the reasons behind that are probably more political than
fear-based.

From 2014:

"North American freight railroads, in general, have accepted the degraded
performance debris can cause. Most of the current solutions are not efficient
for the amount of territory and service required. A road vehicle with rail
wheels based cleaning system would be most useful, allowing one or two workers
to concentrate on the worst locations and move between trouble spots quickly.

\- Steven Belforti, Guilford Rail System"

[https://www.newscientist.com/article/mg22429984-800-locked-o...](https://www.newscientist.com/article/mg22429984-800-locked-
on-lasers-burn-through-leaves-on-train-lines/)

------
StanislavPetrov
Anyone who lives on Long Island or takes the LIRR will let out a bitter laugh
at this article.

> 90.7 percent of trains were on time in November, an improvement of 3.8
> percent over last year

The metrics used by the LIRR were so disconnected from reality that the state
actually passed a law this year mandating that they had to adopt meaningful
standards.

[https://www.newsday.com/long-island/transportation/mta-
lirr-...](https://www.newsday.com/long-island/transportation/mta-lirr-on-time-
measurements-1.29259736)

The entire LIRR system is plagued by cancellations and delays on a daily
basis. There's nothing quite like standing on the train platform looking at
the little digital sign that says, "the 7:08 to PENN is on time" while you
look at your phone and see its 7:25 and the train is still nowhere in sight.

[https://twitter.com/LIRR](https://twitter.com/LIRR)

------
Scoundreller
Would be cool if they could blast a cloud of heat whenever going over a
switch.

There are lots of remote switches that just have a big propane tank to keep
them clear of ice.

Because switching shakes the train around, sometimes a block of ice from an
ice storm 1000km away can dislodge and jam a switch until it’s clear or melts
away.

~~~
delfinom
>There are lots of remote switches that just have a big propane tank to keep
them clear of ice.

Except the switch has to be in the correct position first to get a train over
it. The rail lines in NY including the subway just use natural gas heaters on
most switches.

~~~
gsnedders
In much of Europe electric heaters are used in much the same way. The American
practice of using natural gas heaters always seems… crazy to many of us.
(Especially in areas where there's already electrical supply!)

~~~
catalogia
Electric makes sense if you've got a good clean source of power like nuclear,
solar or wind. But if you're getting power by burning fossil fuels then it
seems more efficient to use that heat directly rather than to use the heat to
generate steam to turn a turbine to turn a generator to produce electricity,
and then turn that electricity back into heat again.

~~~
Scoundreller
For indoor heating, sure, but these are outdoor switches.

Propane/natural gas switch heating is like sitting in-front of a campfire,
while electric would be like having a heating pad on your skin.

Or maybe the electric ones are just blowers too with one central heating point
and a bunch of vents. Dunno.

~~~
catalogia
Some of the electric heaters are blowers ([https://www.rwy.com/products-
rwy/track-heaters-accessories/e...](https://www.rwy.com/products-rwy/track-
heaters-accessories/electric-hot-air-blowers/)) while others use heating
elements in direct contact with the tracks
([https://spectruminfrared.com/railroad-products-and-track-
swi...](https://spectruminfrared.com/railroad-products-and-track-switch-
heaters/flat-jacket-snow-melters-and-crib-heaters/)).

I suspect any of these mechanisms, however they work, are going to be wildly
inefficient. The very premise of melting ice outside in the winter on big
pieces of metal exposed to the elements seems like a huge energy sink. Whether
electric heating is sufficiently more efficient to offset the inefficiencies
in power generation and transmission I couldn't say, but it's far from clear
to me that the 'American method' of using propane is crazy.

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DonHopkins
That test rig in the video looks like a low-tech electro-mechanical Dieselpunk
version of SG-1!

~~~
Scoundreller
Seems like they found a kickstarter promoter to do their video.

------
cbhl
I noticed they needed eye protection in the lab.

I'd love to see how they avoid needing eye protection for people near the
train tracks in the field (presumably some shielding and very careful laser
alignment?).

I'd be particularly interested in whether the lasers are safe on overhead
tracks near populated areas (certain MTA lines in New York are like this).

~~~
wavefunction
I imagine the laser undergoes significant decoherence in practice.

~~~
IIAOPSW
No one is doing quantum leaf removal. I think you mean dispersion.

------
_Microft
There is a video about laser rust removal which is quite amazing. It doesn't
even seem to hurt flesh as the operator intentionally runs it over their hand,
around the 1 minute mark:

[https://www.youtube.com/watch?v=ACGSzBXKONo](https://www.youtube.com/watch?v=ACGSzBXKONo)

~~~
mstade
That’s amazing! Now if only there was something like this wood surfaces, I’d
have a blast (no pun intended) working on my boat then!

------
yellow_lead
Why don't they just put a leaf blower on the front of the train? Maybe a dumb
question. Could be due to stuck wet leaves?

~~~
dokem
The leaves are often partially decomposed into a sticky slime that end up
compressed to the tracks from what I’ve read elsewhere.

~~~
gsnedders
This. Actual dry leaves that can be blown off really aren't the trouble, it's
wet ones that quickly turn into sludge and just get compressed into slicker
and slicker slime that provides no traction.

The current solution in most of the world is essentially high-pressure jets of
water to clean the rail; obviously you eventually reach a point where you
don't have enough pressure to dislodge the goop.

~~~
ars
What about a nylon brush?

~~~
khr
My non-engineer guess is that a nylon brush would be shaved down pretty
quickly by rail contact at typical train speeds, so that it would be
ineffective at removing debris after a very short time.

~~~
gsnedders
Plus I imagine it'll apply nowhere near as much pressure on the track, so
you'd end up needing a lot of brushes and then they'd all be wearing down
quickly at 60mph or so.

------
zaroth
It’s amazing that this isn’t a fire risk. In California they turn off the
electricity when the wind blows during the dry season, and in NE we fire
freaking laser beams at the leaves to eviscerate them.

~~~
cbhl
The New York trains I remember would make sparks all the time; I would suggest
any dry tinder near the tracks would be a risk either way.

California has electrical wires entangled with dry trees after years of
drought. (Trees are tricky, since it takes years after installation for them
to grow tall enough to reach the power lines. In the NE I've seen power
outages caused by tree branches laden with ice from freezing rain sever power
lines.)

~~~
DonHopkins
Why don't the same crews who rake the forests also rake the train tracks? ;)

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matt_the_bass
This seems like a Great idea.

