Traffic jams can be predicted - and research could lead to better road designs
14 July 2010

Traffic jams can be predicted by a new formula developed by mathematicians at the Massachusetts Institute of Technology (MIT).

The research, that predicts the occurrence of “phantom” jams, could lead to better road designs in future.

“Phantom” jams are those not caused by accidents or roadworks, but due to small disturbances in high density traffic such as a driver braking too hard.

This then becomes amplified as the cars behind react more strongly, leading to a self-sustaining jam as cars are forced to stop to avoid slowing cars in front of them.

The formula developed, based on the equations that describe detonation waves caused by explosions, describes how and under what conditions such jams form.

The MIT team said: “Variables such as traffic speed and traffic density are used to calculate the conditions under which a [phantom jam] will form and how fast it will spread.”

The model will not help break up jams once they have formed, but it will allow planners to predict where jams are most likely to occur.

This knowledge could help them to determine safe speed limits, and identify potential accident hotspots where the traffic density is greatest.

Further down the line, it could allow engineers to design roads that prevent traffic from building up dangerously.

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Comments
8

14 July 2010

What flavour is a Phantom Jam? is it ghostberry?

Anyway if this jam theory is applied to those black boxes, we could end up getting fixed penalty fines for causing phantom jams.

The formula could also be used as an excuse for being late for something, sorry boss i had to prevent being in a phantom jam so had to reevaluate my driving in real time using my local knowledge of the roads and fluctuating driving speeds.

14 July 2010

bet it is nice on Toast with a lovely cup of tea

14 July 2010

They could use it to determine safe speed limits? How have they been determining them up til now? Pick a random number based loosely on some breaking distance calculated years ago for rubbish cars and tell people that going faster than said number will kill them, that would be a ridiculous idea........

14 July 2010

Not rocket science is it?

Bad drivers over reacting on the brakes, then bad drivers following too closely and not paying attention = a chain reaction = queue for no reason.

Might be controversial on this website, but the lower speed limits in busy sections do appear to work in stopping the jams (excuse the pun).

Better training and explanation of the causes during the learning process would only help a little as some folks are clearly poorly skilled, and/or have no real interest in driving.

So we're stuck with them...

14 July 2010

[quote beachland2]

What flavour is a Phantom Jam? is it ghostberry?

Anyway if this jam theory is applied to those black boxes, we could end up getting fixed penalty fines for causing phantom jams.

The formula could also be used as an excuse for being late for something, sorry boss i had to prevent being in a phantom jam so had to reevaluate my driving in real time using my local knowledge of the roads and fluctuating driving speeds.

[/quote] I predict bad jams in Asda, in an Asda car park and good jams inside a Tiptree jar, especially the raspberry flavour. But seriously if we stopped building out of town "Superstores" shopped locally (on foot) then many of the horrid jams would cease to exist. Surely shop local is a better answer to jams than most anything? I can walk to and from work, that's got to save congestion. So lets broaden this out, why commute? Why not work locally save fuel, and quit the 2 hour round trips that clog up the roads? Makes sense to me.

14 July 2010

These are a result of the stupid high-level brake lights we now have, causing people to "panic brake" when they see brake lights 6 cars agead. Get rid of this unnecessy rubbish from our cars.

14 July 2010

[quote Autocar]Traffic jams can be predicted by a new formula developed by mathematicians at the Massachusetts Institute of Technology (MIT).
[/quote]

Hardly a new formula, it is just a straightforward application of standing wave theory. (Google it if you really want to know more) In fact a real phantom jam was created a couple of years ago in Japan:

http://www.newscientist.com/article/dn13402

14 July 2010

So the solution if we want independent driving control is we need a quadrupling of lanes on all roads. that way there wont be a car infront to get too close to.

or for busy roads we must just let computers drive for us (in speed terms).

I dont think we will get more roads...

"Good morning Hal" "good morning Dave"

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