
The Man Who Invented Intelligent Traffic Control a Century Too Early - boramalper
http://spectrum.ieee.org/geek-life/history/the-man-who-invented-intelligent-traffic-control-a-century-too-early
======
Osiris
Now someone needs to invent a traffic light system that uses data collected by
sensors and cameras to dynamically adjust traffic lights to improve traffic
flow.

My brother and I envisioned this idea a decade ago. Imagine a system that can
use deep learning techniques to automatically manage traffic to optimize
travel times.

~~~
superuser2
This has been done for quite some time, and it's unclear what value deep
learning would add beyond the arithmetic we've used for a while.

[https://en.wikipedia.org/wiki/Signal_timing](https://en.wikipedia.org/wiki/Signal_timing)

Major cities have Transit Operations Centers or similar where engineers watch
road camera and sensor data (as well as local news and other sources of
information) and direct traffic lights, gates, police, etc. to keep things
moving. There was actually a controversy in London when this control room
manipulated traffic lights so the International Olympic Committee officials
evaluating London would always hit green lights, and perceive the traffic as
better than it actually was.

This may be less apparent in some areas because it is actually done with the
_opposite_ intention: to slow things down. If you seem to be hitting every red
light, it is probably because the local government decided to install a
Traffic Calming program there in the interest of safety / fewer complaints
from the neighbors.

~~~
WalterBright
> This has been done for quite some time, and it's unclear what value deep
> learning would add beyond the arithmetic we've used for a while.

I've seen a lot of these claims, and they're easily debunked by driving
through a city. The usual case is a platoon of 5 cars cruising down an
arterial. A solitary car pulls up on a side street, and the light turns read
for the arterial just in time to stop the platoon for the solitary car. A
sensible algorithm would let the platoon pass first.

There are endless scenarios of these, to the point where the light algorithm
finds a local optima where it is completely out of phase with the traffic and
causes maximum delay and minimum throughput.

A relatively small amount of effort going into cameras and an adaptive system
that minimizes a cost function would save billions of dollars in gas, time,
and unneeded road widening.

~~~
asynchronous13
> A sensible algorithm would let the platoon pass first.

You're taking an example of a sub-optimal local solution and claiming that is
proof that the global solution is sub-optimal. That does not follow.

It could easily be, taking your example, that the platoon of 5 cars _must_
stop at some future light, and the delay for 1 car is the smallest delay
available for those cars. Therefore, stopping for the 1 car reduces the
platoon's total travel time. As the driver, it's easy to think that was dumb
because you'll never see the 15-car wait that was avoided by stopping early
for 1 car.

Essentially, you are claiming that a greedy algorithm for traffic would always
find the globally optimal solution (which we know is not true).

~~~
barrkel
Walter isn't arguing for a greedy algorithm. He's giving an example of a local
inefficiency and a mitigation. Lots of local inefficiencies add up to a global
inefficiency. Illustrating a global inefficiency in itself isn't feasible in
an anecdote. Thus I think your argument by assertion isn't possible to refute:
you can bring up "local inefficiencies don't necessarily mean global
inefficiencies" to dismiss all arguments that the current system is less than
optimal.

Me, I've been stuck at traffic lights for 5 minutes at 2 in the morning, with
no traffic whatsoever around. A very local algorithm would be highly
preferable at that time of night, assuming usual (i.e. very little) traffic at
that hour. It's an extreme example, yes: but there does exist a range of
traffic patterns between the small hours of the morning and rush hour, and the
same amount of global optimization effort is not applied to all hours, for
obvious reasons. Something that could analyse the traffic using cameras and
sensors and optimize wouldn't have to be paid extra to work late at night.

~~~
asynchronous13
Several cities take the even simpler approach of having lights that change
from timed cycles to blinking red/yellow after a certain hour.

~~~
WalterBright
Cars stopping and then starting again costs time, money, fuel, wear & tear,
pollution, etc. It's far from an efficient solution.

------
unexistance
> “Because of my low grades, my father thought that I might be mentally
> retarded,” Adler later wrote. His father took Charles to see a psychologist,
> who said, “You have a remarkable son [with] a vivid imagination. He should
> be encouraged to invent.”

What a psychologist!

~~~
PhasmaFelis
My psychologists said the same, as a child. I suspect it's a stock phrase for
many of them.

Psychologists as a profession are _much_ more comfortable with the idea of
people whose thought processes are unusual, but still effective. It's what
they're for, really.

