http://www.engadget.com/2008/07/23/audi-pilot-program-tells-drivers-how-to-squeeze-the-lemon/

one of the little things that angers me when driving has always been traffic light inefficiencies - i'm not sure this is the solution but it looks like this is a small step in the right direction - the article doesn't mention cost at all - unfortunately this also requires a change in cars - ideally i think you want a system where cars don't require anything because on a large scale i'd imagine more sensors cost less than each car having a sensor but at least in that model the cost is spread out

7/23/2008 9:15:59 AM

It seems to me that it would be more fiscally responsible to take some of the traffic signals and get the cycles working together.

7/23/2008 12:15:07 PM

The new ones flicker/flash [/improvement].

7/23/2008 12:24:11 PM

if the traffuck engineers have done their job properly, sequential lights should be timed to allow you to pass through the green phase at each light if you are going around the speed limit.

for example, if you get stopped at the first light, you should be able to make it through all the lights, once the one you are at turns green.

though the op topic is a little different - I believe that system just tells you how much time until the green phase ends, and converts that into a speed you need to drive to make it.

unfortunately, many sequential lights haven't been synchronized and/or the timing and speed limit haven't been correlated.

[Edited on July 23, 2008 at 12:40 PM. Reason : .]

7/23/2008 12:39:08 PM

its pretty hard to do time that given stuff like people turning and slowing you down, nobody is doing exactly the speed limit, people accelerate different away from lights.

There are also things to consider like the fact that the road on axis X probably has a different number of lights at different intervals than road on axis Y, and that makes it very hard to make sure that when road X should mathematically be green that road Y can never been determined mathematically it is supposed to be green. add onto this the fact that this is also going on at the intersection of road X2-Y1, X3-Y1, X1-Y2 etc. all at the same time.

Tack onto that even further the fact that they have algorithms to decide if someone waiting at an arrow only left turn should get the green turn arrow because even though the road they are trying to cross is supposed to have/does have a green light there have been no cars coming for 15 seconds. The turning car gets the light just as you pull up (assuming you were out of sensor range before) even though just using your math it should have been green for you.

Certain lights also behave differently at different times of the day. if intersection X-Y is a huge road, they might change the timing during rush hour where X-Y2 isnt as busy so the timing is hard to maintain all the way down the line. Not to mention certain lights having different operating modes for weather conditions. Also, the calcs would most likely assume you are first in line, otherwise its hard to guarantee someone 10th in line will be able to make the same lights as the first.

This is just the tip of the iceberg really. I agree there are TONS of moronic things that lights do and just some idiotic intersection designs. But the algorithm to guarantee that if you go straight and get stopped at one light you should be able to make all the lights is orders of magnitude more complicated than you are making it out to be.

7/23/2008 1:20:42 PM

Hey, I just applied to be a traffic engineer. I'll let you know what they are working on.

7/23/2008 1:27:49 PM

I just wrote the application that the DOT uses for managing traffic signal equipment and maintenance... deal with the traffic engineers on a regular basis.

The problem with traffic signals is that you can't have every direction running with optimal timing. Not every signal has the same timing needs or equipment for detection. Some signals are city maintained and some are state maintained. There are several hundred signals in the county and only a handful of technicians so there is only so much work that can be done beyond the regular preventative maintenance, emergency calls, and numerous fake calls from drivers that waste time, not to mention budget constraints.

we could do more to alleviate traffic problems by implementing a logical mass transit system (not the current shit proposal), encouraging telecommuting, alternate work schedules, and with better land zoning. Almost everyone around me at work lives more than 25 miles from the office (some as far as 50 miles).

7/23/2008 11:13:53 PM

Haha, read "telecommuting" as teleporting. Now that would solve all the problems!

One of my coworkers was telling me yesterday how downtown Greensboro is very efficient with the use of traffic lights. Going down any of the major roads you will never have to stop at more than one light. This is a much easier task down there though. I can't imagine the coordination that would be involved for a heavily populated area during rush hour.

7/24/2008 8:44:34 AM

up in gbo they are replacing the wiring to see if that helps.

7/24/2008 8:50:10 AM

^^ they can't guarantee that. but then again the traffic there is like nothing.

7/24/2008 9:07:01 AM

The lights should auto adapt their timing to optimize speed

7/24/2008 9:24:57 AM

Quote :

"alternate work schedules, and with better land zoning"

Totally agree. We need to drop the cul-de-sac mentality.

7/24/2008 10:42:49 AM