M42 active traffic management
M42 active traffic management
Author
Discussion

rewc

Original Poster:

2,187 posts

263 months

Thursday 12th January 2006
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Does anybody know if the variable speed signs are operated automatically or manually. I travelled southwards earlier this evening and the limit varied between 60 and 40 at each gantry. The traffic was bunching and what with having to keep an eye on the limit at the next gantry it was disconcerting.
I also travelled up the A34 between Oxford and the M40. The temporary 40mph limit started miles before tha actual road works and in light traffic itr was galling with noticed saying'speed limit still in force for your safety'. What a joke!

Flat in Fifth

48,849 posts

281 months

Friday 13th January 2006
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untouched by human hand, virtually random limits, and if it wasn't so dangerous it would be a joke.

mybrainhurts

90,809 posts

285 months

Friday 13th January 2006
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Travelling north, why is there a NSL sign where the gantries end...?

First spotted this on a Sunday night with no traffic/no temporary limit.

Immediate thought was is the blanket limit now below 70?

Obviously not but, for that brief moment, the horrible thought of having just gone through several cameras at 70 was quite a bowel shaker......

jonnyb

2,590 posts

282 months

Friday 13th January 2006
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mybrainhurts said:
Travelling north, why is there a NSL sign where the gantries end...?

First spotted this on a Sunday night with no traffic/no temporary limit.

Immediate thought was is the blanket limit now below 70?

Obviously not but, for that brief moment, the horrible thought of having just gone through several cameras at 70 was quite a bowel shaker......


Because if the last gantry is diplaying a limit, 40 for instance, then this is the limit inforce untill you are notified otherwise. If the NSL signs were not there then you could have to do 40 for miles and miles!

GregE240

10,857 posts

297 months

Friday 13th January 2006
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Flat in Fifth said:
untouched by human hand, virtually random limits, and if it wasn't so dangerous it would be a joke.
Couldn't agree more.

I'd love to see the accident stats for this bit of road in say, 2008 for the last 5 years. Theres now an accident on it almost daily, because the poor sods driving on it have to keep looking up at the gantries.

One of the worst peces of road design in the Midlands, for sure.

Flat in Fifth

48,849 posts

281 months

Friday 13th January 2006
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[redacted]

spnracing

1,558 posts

301 months

Friday 13th January 2006
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Have to say that the fact that the limit changes between gantries is just utterly ridiculous.

I drove down the M42 on Wednesday evening and the limit changed at almost every gantry with active cameras on most of them. And its not just in 10MPH increments either, it was 60 to 40 to 60 to 50 to nothing to 40.

I personally think the variable limits on the M25 work very well but the limit generally stays the same with major changes only as traffic slows or there are problems. I can't understand how the M42 gets it so horribly wrong?

jeremyc

28,184 posts

314 months

Friday 13th January 2006
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spnracing said:
I personally think the variable limits on the M25 work very well but the limit generally stays the same with major changes only as traffic slows or there are problems. I can't understand how the M42 gets it so horribly wrong?
I suspect it is because the M42 system is automated, whereas the limits on the M25 are (I believe) determined manually.

Sure it is no excuse for a poorly performing system/software, but it is a very ambitious problem to sense and solve automatically.

Oh, and hi Peter! Long time no see ....

711

806 posts

255 months

Friday 13th January 2006
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GregE240 said:
I'd love to see the accident stats for this bit of road in say, 2008 for the last 5 years. Theres now an accident on it almost daily,

And I wonder what all those accident statistics will be used to justify?

rewc

Original Poster:

2,187 posts

263 months

Friday 13th January 2006
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I guess it must be me as I have checked the official web site and they say its the best thing ever. How come you can't convince anybody, surely the Highways Agency and the Police see what is happening or do they just tow the party line.

ledfoot

777 posts

282 months

Friday 13th January 2006
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The M42 limits were crazy this week.

Started off at 60mph, then next gantry said 50mph there was a camera on it, so time to slam on brakes, then back to 60mph again at next gantry.

The M42 has not even been busy this week, so no need for any limits.

Flat in Fifth

48,849 posts

281 months

Monday 16th January 2006
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Not to mention last night approached a gantry with NSL showing after a long stretch where 60 displayed for no good reason.

Started a positive speed increase just as about to pass underneath the gantry which was about to disappear out of vision at the top of windscreen only to see the NSL change to something with a red circle, too close and no chance to see the number. Anyway kept going at 60, but the folks behind jammed everything on so God knows what happens now. No flash though so fingers crossed.

Funny thing the next gantry immediately lit up with NSL and guess how many vehicles there were in front of me? Precisely nil.

Somebody should be fired for this fiasco. And if not fired out of their job fired out of a bloddy huge cannon.

Flat in Fifth

48,849 posts

281 months

Tuesday 17th January 2006
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Just a thought......

Having read on ukspeedtraps that the M25 cameras allow a 5 minute grace period before anyone gets flashed, considering the frequency that the limits change on M42 will anyone EVER be flashed if the same 5 minute grace period applies?