jeffw
|
| posted on 28/6/14 at 05:40 PM |
|
|
Speed Cameras that know you are pulling a trailer
Had a letter today from Lincolnshire Police ...a notice of intended prosecution  Apparently I went through a speed camera at 69MPH on a
dual-carriageway. Now the speed limit on this dual-carriageway at this point is 70MPH....
So why have I got a NIP....because the camera/radar knew I was pulling a trailer (speed limit 60MPH) and took a photo. I presume it works on size of
doppler radar return.
I was completely unaware that this technology existed in 'Safety' cameras (otherwise I'd have slowed down !). I googled it and it
seems this one camera on the A1 southbound at Great Ponton is the only one (how lucky!) but it might not be.
So gone are the days of setting the cruise at 70MPH with the trailer on the back....needs to be 67MPH !
All the people I know who race/trailer things......be careful out there.
|
|
|
|
|
philw
|
| posted on 28/6/14 at 05:54 PM |
|
|
I think this came in about 10-12 years ago, so they could catch wagons speeding, the first one I knew of was on the M4 near Port Talbot.
Must try harder
|
|
|
mark chandler
|
| posted on 28/6/14 at 07:04 PM |
|
|
That's going to slow me down then
Thanks for the tip.
|
|
|
Andi
|
| posted on 28/6/14 at 07:24 PM |
|
|
Yup someone on RHOCAR last week got the same in an artic
Andi
|
|
|
jeffw
|
| posted on 28/6/14 at 07:28 PM |
|
|
I presume they photograph anything larger than a car and then look at the pictures to see if it is a coach/van/artic/car&trailer and so on.
|
|
|
will121
|
| posted on 28/6/14 at 07:35 PM |
|
|
I thought there was some cameras with Automatic number plate recognition ability to link vehicle type like lorry or vans with different speed limits
and also rumored on a local road with history of multiple road deaths where they manually review the trigger pictures for caravans and trailers and
then prosecute against the lower limit
|
|
|
bi22le
|
| posted on 28/6/14 at 07:39 PM |
|
|
quote:
Originally posted by jeffw
I presume they photograph anything larger than a car and then look at the pictures to see if it is a coach/van/artic/car&trailer and so on.
so did I. They are manned and have to be physically pointed so the operator will know whats coming.
Dont know how the doppler effect would help detect trailers and types of vehicle.
Track days ARE the best thing since sliced bread, until I get a supercharger that is!
Please read my ring story:
http://www.locostbuilders.co.uk/forum/13/viewthread.php?tid=139152&page=1
Me doing a sub 56sec lap around Brands Indy. I need a geo set up! http://www.youtube.com/watch?v=EHksfvIGB3I
|
|
|
jeffw
|
| posted on 28/6/14 at 07:48 PM |
|
|
Well...when I used to maintain and operate Radar systems in the RN it was pretty obvious from the size of the return that something large was being
pinged, but you may have more experience of Doppler radars than I do..
And no....the yellow box wasn't a manned unit.
[Edited on 28/6/14 by jeffw]
|
|
|
Canada EH!
|
| posted on 28/6/14 at 08:06 PM |
|
|
When I worked police radar the machine would lock on a city bus doing 40 km/h and not even see a speeding motorcycle passing the bus doing 80 in a 60
km/h zone.
Size does matter with radar.
Not so with laser the little red dot goes on the vehicle you want to look at.
|
|
|
coozer
|
| posted on 28/6/14 at 08:18 PM |
|
|
So, why go through at 69mph when the speed limit is 60mph?
1972 V8 Jago
1980 Z750
|
|
|
02GF74
|
| posted on 28/6/14 at 08:27 PM |
|
|
quote:
Originally posted by jeffw
Well...when I used to maintain and operate Radar systems in the RN it was pretty obvious from the size of the return that something large was being
pinged, but you may have more experience of Doppler radars than I do..
interesting - my understanding, and it may well be wrong, is the strength of the return is proportional to the area of the object (not its length as I
assume the radar is facing the rear of the vehicle - I would imagine that a trailer with a 7 kit car on top would give a similar signal to the towing
car - a covered box trailer would give a much larger signal.
A manuall process does not sound practical as I cannot image someone sifting through images of vehicles going at 10 mph less than the speed limit to
figure out if they are pulling trailers, maybe the technology is there to do this??? 
[Edited on 28/6/14 by 02GF74]
|
|
|
theprisioner
|
| posted on 28/6/14 at 08:35 PM |
|
|
I think you are possibly over analysing. Why not temporally set the limit to 60mph of the speed detector, look at all the images of vehicles
(manually) that are committing a prosecutable offence then discard the other images. Tedious but possible.
http://sylvabuild.blogspot.com/
http://austin7special.blogspot.co.uk/
|
|
|
jeffw
|
| posted on 28/6/14 at 08:39 PM |
|
|
quote:
Originally posted by coozer
So, why go through at 69mph when the speed limit is 60mph?
Let me think about that for a moment.....I guess for the same reason that any of us speed really.
quote:
interesting - my understanding, and it may well be wrong, is the strength of the return is proportional to the area of the object (not its
length as I assume the radar is facing the rear of the vehicle - I would imagine that a trailer with a 7 kit car on top would give a similar signal to
the towing car - a covered box trailer would give a much larger signal.
A manuall process does not sound practical as I cannot image someone sifting through images of vehicles going at 10 mph less than the speed limit to
figure out if they are pulling trailers, maybe the technology is there to do this???
I presume (and don't have any technical specs to back this up) that it is a relatively high frequency low strength system. When a car and
trailer go through the beam it will present a larger return from the rear 3/4. The trick here will be to set the system to trigger when a large
return is doing more than, say. 60mph. That will then enable you to manual review the images/data and ascertain if it is a Lorry or car & trailer
and apply the correct limits/send out the NIP.
Please don't think I'm suggesting that I wasn't doing anything wrong here....just trying to alert other people who tow who also may
'drift' over the limit on occasions. 9 mph over the limit isn't really the crime of the century either.
[Edited on 28/6/14 by jeffw]
|
|
|
coozer
|
| posted on 28/6/14 at 08:49 PM |
|
|
My understanding of these scammera's is that the beam travels up and down and measures the height to see if the vehicle is high, ie a truck.
Didn't think this applied to trailers but maybe it triggered because it was low? Then some one at the centre rubbing his hands see's its a
trailer.
I got flashed on a single carriageway many years ago at 45mph driving a rigid lorry. Now I always ensure I'm under the appropriate speed limit
around these places.
Shame the technology doesn't exist to catch speeding caravan drivers overtaking in the outside lane.
Just had another read of your first post there, you say the dual carriageway speed is 70mph. Its not, its national speed limit so with a trailer, of
any kind its 60mph, and white van mans speed is 60mph as well (if the van is over 2t GVW) And is 50 for a truck, 30 for a git big load with an escort
even slower for wide loads, the list of speed limits is quite large...
[Edited on 28/6/14 by coozer]
1972 V8 Jago
1980 Z750
|
|
|
jeffw
|
| posted on 28/6/14 at 08:56 PM |
|
|
Or catch lorry drivers spending 10miles overtaking each other on a dual carriageway with a speed differential of less than 1mph. Everyone has their
pet motoring hates, when I am towing it is muppets sitting in the middle lane at less than 60mph....
|
|
|
chrism
|
| posted on 28/6/14 at 11:42 PM |
|
|
quote:
Originally posted by jeffw
when I am towing it is muppets sitting in the middle lane at less than 60mph....
They should just make undertaking legal like in some other countries.
----------------------------
A little hard work never killed anyone, but why take the risk!
-----------------------------
|
|
|
coyoteboy
|
| posted on 28/6/14 at 11:53 PM |
|
|
The number of people I see towing at a frighteningly high speed is remarkable. Seems very few have had to make evasive action and seen how towing a
trailer really messes with that ability at speed. The lower limit is there for a reason.
Not trying to be smug, just saying drive to conditions, and rarely do the conditions of towing work with driving fast.
|
|
|
bi22le
|
| posted on 29/6/14 at 12:07 AM |
|
|
quote:
Originally posted by jeffw
quote:
Originally posted by coozer
So, why go through at 69mph when the speed limit is 60mph?
Let me think about that for a moment.....I guess for the same reason that any of us speed really.
quote:
interesting - my understanding, and it may well be wrong, is the strength of the return is proportional to the area of the object (not its
length as I assume the radar is facing the rear of the vehicle - I would imagine that a trailer with a 7 kit car on top would give a similar signal to
the towing car - a covered box trailer would give a much larger signal.
A manuall process does not sound practical as I cannot image someone sifting through images of vehicles going at 10 mph less than the speed limit to
figure out if they are pulling trailers, maybe the technology is there to do this???
I presume (and don't have any technical specs to back this up) that it is a relatively high frequency low strength system. When a car and
trailer go through the beam it will present a larger return from the rear 3/4. The trick here will be to set the system to trigger when a large
return is doing more than, say. 60mph. That will then enable you to manual review the images/data and ascertain if it is a Lorry or car & trailer
and apply the correct limits/send out the NIP.
Please don't think I'm suggesting that I wasn't doing anything wrong here....just trying to alert other people who tow who also may
'drift' over the limit on occasions. 9 mph over the limit isn't really the crime of the century either.
[Edited on 28/6/14 by jeffw]
my knowledge is little more than a good education and being an proper engineer (not just chuck it in my title for fun and profit), not radar related.
The modern units may have this tech but would have to be backed up by human approval, surely. I know they don't send most tickets out with a
human check but this is quite specific. I take it thay pulled the common illegal stunt of providing no evidence and threatening you with additional
costs or Court if you want proof?
It sounds like this is your specialism, can they fit intelligent emitters and receivers in these small yellow boxes that would capture this sort of
detail? Considering the market and associated cost I just don't see it.
Track days ARE the best thing since sliced bread, until I get a supercharger that is!
Please read my ring story:
http://www.locostbuilders.co.uk/forum/13/viewthread.php?tid=139152&page=1
Me doing a sub 56sec lap around Brands Indy. I need a geo set up! http://www.youtube.com/watch?v=EHksfvIGB3I
|
|
|
morcus
|
| posted on 29/6/14 at 12:59 AM |
|
|
quote:
Originally posted by chrism
They should just make undertaking legal like in some other countries.
It's not illegal to pass someone in the middle lane while your in the first lane. It only gets dodgy if your changing lanes to do it.
In a White Room, With Black Curtains, By the Station.
|
|
|
jeffw
|
| posted on 29/6/14 at 04:32 AM |
|
|
quote:
Originally posted by coyoteboy
The number of people I see towing at a frighteningly high speed is remarkable. Seems very few have had to make evasive action and seen how towing a
trailer really messes with that ability at speed. The lower limit is there for a reason.
Not trying to be smug, just saying drive to conditions, and rarely do the conditions of towing work with driving fast.
Interesting then that in the most of the rest of Europe it is legal to tow at the national speed limit (130Km/h in France for instance).
|
|
|
jeffw
|
| posted on 29/6/14 at 04:38 AM |
|
|
quote:
Originally posted by bi22le
quote:
Originally posted by jeffw
I presume (and don't have any technical specs to back this up) that it is a relatively high frequency low strength system. When a car and
trailer go through the beam it will present a larger return from the rear 3/4. The trick here will be to set the system to trigger when a large
return is doing more than, say. 60mph. [bold]That will then enable you to manual review the images/data and ascertain if it is a Lorry or car &
trailer and apply the correct limits/send out the NIP[/bold]
Please don't think I'm suggesting that I wasn't doing anything wrong here....just trying to alert other people who tow who also may
'drift' over the limit on occasions. 9 mph over the limit isn't really the crime of the century either.
[Edited on 28/6/14 by jeffw]
my knowledge is little more than a good education and being an proper engineer (not just chuck it in my title for fun and profit), not radar related.
The modern units may have this tech but would have to be backed up by human approval, surely. I know they don't send most tickets out with a
human check but this is quite specific. I take it thay pulled the common illegal stunt of providing no evidence and threatening you with additional
costs or Court if you want proof?
It sounds like this is your specialism, can they fit intelligent emitters and receivers in these small yellow boxes that would capture this sort of
detail? Considering the market and associated cost I just don't see it.
It would be trivial to reduce the speed gate on the radar electronics to 60MPH for objects larger then the standard car/SUV. Then a manual review of
the evidence would be required. My understanding is that this is limited to this one unit on the A1 currently although there is no way of knowing
that as there would be no external signs that the unit was enabled. If you can do it to one then the chances are you can do it to all.
|
|
|
02GF74
|
| posted on 29/6/14 at 07:34 AM |
|
|
quote:
Originally posted by chrism
quote:
Originally posted by jeffw
when I am towing it is muppets sitting in the middle lane at less than 60mph....
They should just make undertaking legal like in some other countries.
No it should be illegal and heavily fineable if somebody sits in the outer lanes when the inside lane is clear.
|
|
|
ashg
|
| posted on 29/6/14 at 07:49 AM |
|
|
Jeff I'm sure I told you to watch out for that at the Christmas doo. I got done for exactly the same thing. Same speed same road trailer on
back!
Apparently gatsos can enforce three different speed limits depending on the vehicle size
Anything With Tits or Wheels Will cost you MONEY!!
Haynes Roadster (Finished)
Exocet (Finished & Sold)
New Project (Started)
|
|
|
jeffw
|
| posted on 29/6/14 at 08:57 AM |
|
|
Don't remember you mentioning Ash....lesson learnt though...
|
|
|
bigfoot4616
|
| posted on 29/6/14 at 09:43 AM |
|
|
quote:
Originally posted by morcus
quote:
Originally posted by chrism
They should just make undertaking legal like in some other countries.
It's not illegal to pass someone in the middle lane while your in the first lane. It only gets dodgy if your changing lanes to do it.
i do it quite regularly, better option than the car with a boat trailer on that used the outside lane on the M56 last night to get past a MLH, i just
cruised past without leaving the inside lane.
|
|
|
