Speed Limits under 30MPH

The study of British and Irish roads - their construction, numbering, history, mapping, past and future official roads proposals and general roads musings.

There is a separate forum for Street Furniture (traffic lights, street lights, road signs etc).

Registered users get access to other forums including discussions about other forms of transport, driving, fantasy roads and wishlists, and roads quizzes.

Moderator: Site Management Team

Post Reply
User avatar
Helvellyn
Member
Posts: 24664
Joined: Tue Apr 04, 2006 22:31
Location: High Peak

Re: Speed Limits under 30MPH

Post by Helvellyn »

Phil wrote: Wed Oct 28, 2020 20:20
Helvellyn wrote: Tue Oct 27, 2020 19:10 Oh dear. Talk about speed limiters. Why are some people so desperate to have machines watching over everything everyone does?
Because Human beings cannot be trusted to 'do the right thing'!

We have been through this on other threads over the years - your hatred of 'systems' that 'track' you is the inevitable consequences of others not following the rules and a method of weeding out the dishonest needing to be in place.

If everyone was honest and well behaved there would be no need for a criminal justice system.

Regardless of whether you personally be a paragon of virtue behind the wheel - the number of prosecutions for motoring offences PROVES that a large chunk of the UK population are not!

How would you like it if one of your nearest and dearest gets mown down by a car going over the posted limit or a lorry that has defective brakes as occurred in Bath a few years ago. (In that case the lorry had a warning light driven by a 'machine watching over it' telling the driver that the brakes were defective - yet the operator of the lorry knowingly let it to continue to be used).

We owe it to society as a whole to ensure that people with the potential to do harm are stopped if possible - and yes, that does entail a significant sacrifice of personal liberty to happen, but something that is beneficial overall.
I'd rather take my chances (which are good - you really shouldn't be all that scared about the chances of being in a serious accident in this country - it's about 2 1/2 times more likely than deaths from falling down stairs, and most people aren't clamouring about that). I know all the reasons for these things but that doesn't mean I agree with them (and before anyone starts that doesn't mean go for the opposite extreme either). Not because I want to drive like an idiot, but because I find the ever-increasing level of nannying, the constant "no-one can be trusted, you've all got to be treated like children" attitude, the idea that because some people aren't responsible we should assume no-one is - that is not the sort of world I want to live in, not in the slightest. I hate the idea of everything being monitored (even if just locally, with no storage). I hate the "you need looking after" attitude. I suffer from depression and this is one of the contributions to it. That is simply not the world I want to live in, and if the price of not living in it is slightly more risk it's a risk I'd be more than happy to take.

The intentions behind it all are good (but you know what they say about the road to hell) but personally speaking the effects are making a world I find bloody unpleasant.

Far too often the response to a lack of responsibility in some quarters is to remove it from all. This is insulting and patronising to the majority, and hits the least hard at the people who need to be on the receiving end of it the most (those most likely to ignore and / or work their way around it). It's looking for easy answers.

No doubt cue someone calling all of that nonsense simply because they don't feel the same way and are incapable of understanding how anyone can see the world differently than they do (usually boils down to "it doesn't bother me so it shouldn't bother you.")
Phil
Member
Posts: 2271
Joined: Sun Dec 15, 2002 18:03
Location: Burgess Hill,W Sussex, UK

Re: Westminster 20 limit

Post by Phil »

KeithW wrote: Wed Oct 28, 2020 21:34
Phil wrote: Wed Oct 28, 2020 20:33

I would suggest something far less infrastructure intensive.

If we can update freeview digital TV revivers 'over the air' without the need for mobile or internet technology then surely the same can happen with a speed limit database in vehicles. Link that database to a GPS receiver and a speed limiter and you have a robust solution that does not rely on lots of 'nodes' needing to be installed. Yes it won't be quite as good because it cannot reasonably be made to react quick enough to changes in Variable limits on motorways, but its a start and one that could have a significant impact on the KSI statistics in urban areas (which is where most incidents occur anyway).
The problem is that these updates need to be user initiated and occur inside the receiver , it rescans. Nor can freeview digitial TV transmit a new database to a satnav not least as they are
1) Proprietary
2) Require large directional antennae
3) They transmit TV sound and images.

Sorry bud if this worked nobody would need an ISP. I would love to see your design for a freeview receiver and aerial that would work buried under tarmac.

Which raises another issue, where will these nodes get their power ? A couple of AA cells wont cut it.
Firstly, the Internet requires a large quantity of information to be sent as well as received. A freeview set top box only needs to receive information (one way communication) to work (unless you want to use interactive services) and thats precisely why updates can be done in the same way as TV broadcasts.

Secondly the, quantity of data required to update a speed limit data is tiny in comparison to TV services, moreover the loss of signal is not a problem if the database is stored in the vehicle with the only reason to receive broadcast information being to update the information every few weeks*. You do not need large directional areas for this - a standard radio aerial would be sufficient and the update information can be broadcast in exactly the same way as Absolute, Kiss, Virgin, or BBC local radio are!

Thirdly free view boxes are only 'proprietary' because of the 'operating system' they use to run themselves. TV broadcast signals MUST fall into a specific Government mandated frequency spectrum while the MPEG encoding used is an agreed industry standard and does not vary between manufacturers. In effect the ONLY thing that makes each box different is its operating system - and just as Sky used to provide boxes by multiple manufacturers yet all running the same software, the same is perfectly true of a state mandated speed limit system.


* By excluding things like Variable speed limits etc there is no requirement to have a 'live' feed. Most KSI incidents occur in urban areas or rural roads where speed limits do not change for years on end.
A9NWIL
Member
Posts: 3319
Joined: Fri Jul 01, 2016 02:36

Re: Westminster 20 limit

Post by A9NWIL »

Phil wrote: Fri Oct 30, 2020 17:28
KeithW wrote: Wed Oct 28, 2020 21:34
Phil wrote: Wed Oct 28, 2020 20:33

I would suggest something far less infrastructure intensive.

If we can update freeview digital TV revivers 'over the air' without the need for mobile or internet technology then surely the same can happen with a speed limit database in vehicles. Link that database to a GPS receiver and a speed limiter and you have a robust solution that does not rely on lots of 'nodes' needing to be installed. Yes it won't be quite as good because it cannot reasonably be made to react quick enough to changes in Variable limits on motorways, but its a start and one that could have a significant impact on the KSI statistics in urban areas (which is where most incidents occur anyway).
The problem is that these updates need to be user initiated and occur inside the receiver , it rescans. Nor can freeview digitial TV transmit a new database to a satnav not least as they are
1) Proprietary
2) Require large directional antennae
3) They transmit TV sound and images.

Sorry bud if this worked nobody would need an ISP. I would love to see your design for a freeview receiver and aerial that would work buried under tarmac.

Which raises another issue, where will these nodes get their power ? A couple of AA cells wont cut it.
Firstly, the Internet requires a large quantity of information to be sent as well as received. A freeview set top box only needs to receive information (one way communication) to work (unless you want to use interactive services) and thats precisely why updates can be done in the same way as TV broadcasts.

Secondly the, quantity of data required to update a speed limit data is tiny in comparison to TV services, moreover the loss of signal is not a problem if the database is stored in the vehicle with the only reason to receive broadcast information being to update the information every few weeks*. You do not need large directional areas for this - a standard radio aerial would be sufficient and the update information can be broadcast in exactly the same way as Absolute, Kiss, Virgin, or BBC local radio are!

Thirdly free view boxes are only 'proprietary' because of the 'operating system' they use to run themselves. TV broadcast signals MUST fall into a specific Government mandated frequency spectrum while the MPEG encoding used is an agreed industry standard and does not vary between manufacturers. In effect the ONLY thing that makes each box different is its operating system - and just as Sky used to provide boxes by multiple manufacturers yet all running the same software, the same is perfectly true of a state mandated speed limit system.


* By excluding things like Variable speed limits etc there is no requirement to have a 'live' feed. Most KSI incidents occur in urban areas or rural roads where speed limits do not change for years on end.
There is no reason why vehicles cant have something for variable speed limits to be done in real time, the main system could just be set up to tell the vehicle its entering a variable zone and to use a different live system, as opposed to the main less frequently updated system.
Formerly known as 'lortjw'
User avatar
KeithW
Member
Posts: 19205
Joined: Thu Dec 04, 2014 13:25
Location: Marton-In-Cleveland North Yorks

Re: Westminster 20 limit

Post by KeithW »

Phil wrote: Fri Oct 30, 2020 17:28
Firstly, the Internet requires a large quantity of information to be sent as well as received. A freeview set top box only needs to receive information (one way communication) to work (unless you want to use interactive services) and thats precisely why updates can be done in the same way as TV broadcasts.

Secondly the, quantity of data required to update a speed limit data is tiny in comparison to TV services, moreover the loss of signal is not a problem if the database is stored in the vehicle with the only reason to receive broadcast information being to update the information every few weeks*. You do not need large directional areas for this - a standard radio aerial would be sufficient and the update information can be broadcast in exactly the same way as Absolute, Kiss, Virgin, or BBC local radio are!

Thirdly free view boxes are only 'proprietary' because of the 'operating system' they use to run themselves. TV broadcast signals MUST fall into a specific Government mandated frequency spectrum while the MPEG encoding used is an agreed industry standard and does not vary between manufacturers. In effect the ONLY thing that makes each box different is its operating system - and just as Sky used to provide boxes by multiple manufacturers yet all running the same software, the same is perfectly true of a state mandated speed limit system.


* By excluding things like Variable speed limits etc there is no requirement to have a 'live' feed. Most KSI incidents occur in urban areas or rural roads where speed limits do not change for years on end.
Noe of which alters the fact that you are not updating a single device. Such a system needs to be able to simultaneously roll out updates to a large number of vehicles and do so without disrupting the operation of vehicles that may be doing 70 mph down a motorway at the time. Having loaded new map configurations into an automotive GPS system I have to tell you that the files are large. Moreover a check would have to be run to ensure the downloaded data was valid. To make matters worse there is no common format for this data. GPS updates from Gsrmin dont work for a TomTom system. As for freeview boxes the bandwidth for the TV/Sound payload data is high but that for metadata is low so typically at best you will get a notification that new channels are available which requires the user to initiate a retune.

A better analogy than freeview channel updates is operating system software updates such as IOS and Windows. For such a system at the very least you need a checksum authentication that the download was accurate and the ability to roll back. Real time software design is far from simple and updates may take a considerable time. You also need to guard against malware and hacking. This is a hot topic in the software business, the general opinion is that existing connected car systems are extremely vulnerable to attack which is why many manufacturers including Ford will NOT roll out updates wirelessly.
https://www.information-age.com/connect ... 123464539/

An you imagine the chaos that would ensue if a spoofed update set the speed limit on the A406 to 5 mph or the M1 to 100 mph ?

The update for my Ford SatNav was eventually done by USB stick and took a couple of hours.

At present it is urban areas that are changing fastest as councils roll out 20 mph speed limits. Most rural roads are NSL outside built up areas - see my old friend the B1040.
https://www.google.co.uk/maps/@52.49158 ... 312!8i6656

The speed limit on the A174 has not changed since the road opened in the 1970's but the speed limit on my local urban roads have been up and down like a yoyo.

Last but far from least current car navigation systems are NOT interfaced to the vehicle management system so there is no way a speed limit in the navigation database can set the limiter.
A9NWIL
Member
Posts: 3319
Joined: Fri Jul 01, 2016 02:36

Re: Westminster 20 limit

Post by A9NWIL »

KeithW wrote: Sat Oct 31, 2020 14:05Noe of which alters the fact that you are not updating a single device. Such a system needs to be able to simultaneously roll out updates to a large number of vehicles and do so without disrupting the operation of vehicles that may be doing 70 mph down a motorway at the time. Having loaded new map configurations into an automotive GPS system I have to tell you that the files are large. Moreover a check would have to be run to ensure the downloaded data was valid. To make matters worse there is no common format for this data. GPS updates from Gsrmin dont work for a TomTom system. As for freeview boxes the bandwidth for the TV/Sound payload data is high but that for metadata is low so typically at best you will get a notification that new channels are available which requires the user to initiate a retune.
1st off if its a government mandated system then all vehicle manufactures would have to utilise the same system. 2nd while all vehicles may receive the file at once, if the car's ECU/EMU is busy then the update would apply later when its able to. 3rd the file could be played out in a loop for several days in advance of the date when it was to take place, giving all vehicles time to check that they have received and implemented the right data and ensure that all vehicles switch to the new speeds at once.
4th why should the files be as big as maps? maps are large files as they have images in them as well as the GPS data. a file matching speeds to GPS data is just a mass of numbers which should be much smaller.
Formerly known as 'lortjw'
User avatar
KeithW
Member
Posts: 19205
Joined: Thu Dec 04, 2014 13:25
Location: Marton-In-Cleveland North Yorks

Re: Westminster 20 limit

Post by KeithW »

lotrjw wrote: Sat Oct 31, 2020 15:11
KeithW wrote: Sat Oct 31, 2020 14:05Noe of which alters the fact that you are not updating a single device. Such a system needs to be able to simultaneously roll out updates to a large number of vehicles and do so without disrupting the operation of vehicles that may be doing 70 mph down a motorway at the time. Having loaded new map configurations into an automotive GPS system I have to tell you that the files are large. Moreover a check would have to be run to ensure the downloaded data was valid. To make matters worse there is no common format for this data. GPS updates from Gsrmin dont work for a TomTom system. As for freeview boxes the bandwidth for the TV/Sound payload data is high but that for metadata is low so typically at best you will get a notification that new channels are available which requires the user to initiate a retune.
1st off if its a government mandated system then all vehicle manufactures would have to utilise the same system. 2nd while all vehicles may receive the file at once, if the car's ECU/EMU is busy then the update would apply later when its able to. 3rd the file could be played out in a loop for several days in advance of the date when it was to take place, giving all vehicles time to check that they have received and implemented the right data and ensure that all vehicles switch to the new speeds at once.
4th why should the files be as big as maps? maps are large files as they have images in them as well as the GPS data. a file matching speeds to GPS data is just a mass of numbers which should be much smaller.

GPS maps are multimedia binary databases with both the map images and speed limits keyed to a database record, partial updates are tricky and somewhat risky, as for the UK government mandating it , lots of luck with it, any such system has to be at least europe wide and probably global in scope.

The nearest thing to a standard is the Navigation Data Standard (NDS). This governed by an association registered in Germany. Members are automotive OEMs, map data providers, and navigation device/application providers.

The aim is to develop a standardized binary database format that allows the exchange of navigation data between different systems separating navigation software from navigation data allowing NDS databases to support incremental updates, protection against illegal use, and compactness. Note this is an aim NOT a widespread reality. The first NDS based system was rolled out this September and its only available on an iPhone running IOS 12.0 or higher or Android
https://apps.apple.com/us/app/tomtom-go ... d884963367

Given the spectacular lack of success of software systems produced by UK government departments I wouldnt hold your breath waiting for a masterpiece from them.

As for broadcasting changes for EMU's and ECU's - forget about it, the process of changing this usually requires a specific dealer intervention or an unauthorised hack. There is no cross industry standard implementation. The reality is that your car is likely to be manufactured overseas anywhere from China, South Korea and Japan to Wolfsburg and the satnav components licensed from a specialist such as TomTom to Garmin.

Guess the length of the software proposal/update development/testing/approval process for a global release ?

Then tell me what the speed limit for this unclassified road should be.
https://www.google.se/maps/@54.4215214, ... 6656?hl=en

The answer is 'slow enough to avoid a wandering sheep'

If you really want to reduce ksi's on urban roads the answer is to improve the segregation of motorised and non motorised traffic. A large percentage of such incidents are the result of pedestrians stepping into the road without looking or taking a chance on unauthorised crossings. In the USA an NHTSA traffic survey reported that the vast majority of such injuries occurred on city streets and a rising hazard is the result of the adoption of battery and hybrid cars as many pedestrians rely on sound cues rather than vision. An additional hazard is pedestrians using mobile phones when walking and becoming distracted, the highest risk of all is incurred by the alcohol impaired pedestrian aka the drunk wobbling across the road at midnight.

https://www.trafficsafetystore.com/blog ... accidents/
see also
https://www.cdc.gov/motorvehiclesafety/ ... talities-0

A bug bear of mine is the growth of suburban link roads with little or no provision of safe road crossings. These unsurprisingly are a high risk, we had one such fatality a few weeks ago just here.
https://www.google.se/maps/@54.5277039, ... 8192?hl=en
There is a nice pedestrian/cycle path but crossing the D2 road is your problem. No zebra or crossing signal is provided. But hey a path coming from a pub - what could possibly go wrong !
Phil
Member
Posts: 2271
Joined: Sun Dec 15, 2002 18:03
Location: Burgess Hill,W Sussex, UK

Re: Westminster 20 limit

Post by Phil »

KeithW wrote: Sat Oct 31, 2020 14:05
Phil wrote: Fri Oct 30, 2020 17:28
Firstly, the Internet requires a large quantity of information to be sent as well as received. A freeview set top box only needs to receive information (one way communication) to work (unless you want to use interactive services) and thats precisely why updates can be done in the same way as TV broadcasts.

Secondly the, quantity of data required to update a speed limit data is tiny in comparison to TV services, moreover the loss of signal is not a problem if the database is stored in the vehicle with the only reason to receive broadcast information being to update the information every few weeks*. You do not need large directional areas for this - a standard radio aerial would be sufficient and the update information can be broadcast in exactly the same way as Absolute, Kiss, Virgin, or BBC local radio are!

Thirdly free view boxes are only 'proprietary' because of the 'operating system' they use to run themselves. TV broadcast signals MUST fall into a specific Government mandated frequency spectrum while the MPEG encoding used is an agreed industry standard and does not vary between manufacturers. In effect the ONLY thing that makes each box different is its operating system - and just as Sky used to provide boxes by multiple manufacturers yet all running the same software, the same is perfectly true of a state mandated speed limit system.


* By excluding things like Variable speed limits etc there is no requirement to have a 'live' feed. Most KSI incidents occur in urban areas or rural roads where speed limits do not change for years on end.



The only requirement is that actuall changes to speed limits are properly planned so as to ensure there are a couple of months between the order being made and the date it comes force Just as Windows or your set top box will advise you of an update and give you the choice of applying it when you turn your device off, so it is that a speed limit system could download a new copy of the data base at any time - but only install it when you start your car.


Noe of which alters the fact that you are not updating a single device. Such a system needs to be able to simultaneously roll out updates to a large number of vehicles and do so without disrupting the operation of vehicles that may be doing 70 mph down a motorway at the time. Having loaded new map configurations into an automotive GPS system I have to tell you that the files are large. Moreover a check would have to be run to ensure the downloaded data was valid. To make matters worse there is no common format for this data. GPS updates from Gsrmin dont work for a TomTom system. As for freeview boxes the bandwidth for the TV/Sound payload data is high but that for metadata is low so typically at best you will get a notification that new channels are available which requires the user to initiate a retune.

A better analogy than freeview channel updates is operating system software updates such as IOS and Windows. For such a system at the very least you need a checksum authentication that the download was accurate and the ability to roll back. Real time software design is far from simple and updates may take a considerable time. You also need to guard against malware and hacking. This is a hot topic in the software business, the general opinion is that existing connected car systems are extremely vulnerable to attack which is why many manufacturers including Ford will NOT roll out updates wirelessly.
https://www.information-age.com/connect ... 123464539/

An you imagine the chaos that would ensue if a spoofed update set the speed limit on the A406 to 5 mph or the M1 to 100 mph ?

The update for my Ford SatNav was eventually done by USB stick and took a couple of hours.

At present it is urban areas that are changing fastest as councils roll out 20 mph speed limits. Most rural roads are NSL outside built up areas - see my old friend the B1040.
https://www.google.co.uk/maps/@52.49158 ... 312!8i6656

The speed limit on the A174 has not changed since the road opened in the 1970's but the speed limit on my local urban roads have been up and down like a yoyo.

Last but far from least current car navigation systems are NOT interfaced to the vehicle management system so there is no way a speed limit in the navigation database can set the limiter.
You still don't get it. Stop thinking about what is currently installed in cars and the reliance on private companies.

If it becomes a legal requirement to have the device fitted then the STATE will determine the standards and photocalls used to ensure ALL vehicles are compatible (just as they do with a myriad of other things on motor vehicles already).

If you drop the need for 'instant' speed limit notification (i.e. don't have it reduce form 70mph to 40mph when the VMS on a Smart motorway is activated) then updates can occur at ANY TIME* thus minimising issues that can occur with a lack of coverage.

An active speed limiter would thus be a NEW stated backed system - not a bodged Garmin, Tom Tom / Ford system as fitted to cars today. Updates would be provided by the VOSA and fed into an 'industry standard' black box which uses a combination of GPS and road data to determine the maximum limit. An internal calender would ensure that where limits change the new limit would not apply until the 'start date' was reached.

Finally it should be noted that we are talking about a speed limiter here! Its a fact that very few roads have limits that go up - they mostly go down so the chances of being artificiality kept below the legal limit is going to rare. Moreover if the limit changes to a lower one, it is still up to the driver to respond - saying "but my speed limiter didn't kick in is NOT a satisfactory defence. The whole point of such a system being that it is a backup safety system which should never actually have to be activated if drivers obey the posted limit. (Note, things like airbags are not designed to be routinely used so the principle of having things installed for safety but not normally used already happens).

* If a road authority wishes to permanently reduce the speed limit I believe it has to arrange for a TRO to be published, consulted on and then only enacted after sufficient notice has been given. In other words it takes weeks - if not months (the time frame can of course be extended if necessary) - plenty of time to allow cars to update themselves with the new restrictions ready for the exact date it goes live.
User avatar
Bryn666
Elected Committee Member
Posts: 35755
Joined: Thu Jun 20, 2002 20:54
Contact:

Re: Westminster 20 limit

Post by Bryn666 »

Phil wrote: Sat Oct 31, 2020 18:39
KeithW wrote: Sat Oct 31, 2020 14:05
Phil wrote: Fri Oct 30, 2020 17:28
Firstly, the Internet requires a large quantity of information to be sent as well as received. A freeview set top box only needs to receive information (one way communication) to work (unless you want to use interactive services) and thats precisely why updates can be done in the same way as TV broadcasts.

Secondly the, quantity of data required to update a speed limit data is tiny in comparison to TV services, moreover the loss of signal is not a problem if the database is stored in the vehicle with the only reason to receive broadcast information being to update the information every few weeks*. You do not need large directional areas for this - a standard radio aerial would be sufficient and the update information can be broadcast in exactly the same way as Absolute, Kiss, Virgin, or BBC local radio are!

Thirdly free view boxes are only 'proprietary' because of the 'operating system' they use to run themselves. TV broadcast signals MUST fall into a specific Government mandated frequency spectrum while the MPEG encoding used is an agreed industry standard and does not vary between manufacturers. In effect the ONLY thing that makes each box different is its operating system - and just as Sky used to provide boxes by multiple manufacturers yet all running the same software, the same is perfectly true of a state mandated speed limit system.


* By excluding things like Variable speed limits etc there is no requirement to have a 'live' feed. Most KSI incidents occur in urban areas or rural roads where speed limits do not change for years on end.

The only requirement is that actuall changes to speed limits are properly planned so as to ensure there are a couple of months between the order being made and the date it comes force Just as Windows or your set top box will advise you of an update and give you the choice of applying it when you turn your device off, so it is that a speed limit system could download a new copy of the data base at any time - but only install it when you start your car.


Noe of which alters the fact that you are not updating a single device. Such a system needs to be able to simultaneously roll out updates to a large number of vehicles and do so without disrupting the operation of vehicles that may be doing 70 mph down a motorway at the time. Having loaded new map configurations into an automotive GPS system I have to tell you that the files are large. Moreover a check would have to be run to ensure the downloaded data was valid. To make matters worse there is no common format for this data. GPS updates from Gsrmin dont work for a TomTom system. As for freeview boxes the bandwidth for the TV/Sound payload data is high but that for metadata is low so typically at best you will get a notification that new channels are available which requires the user to initiate a retune.

A better analogy than freeview channel updates is operating system software updates such as IOS and Windows. For such a system at the very least you need a checksum authentication that the download was accurate and the ability to roll back. Real time software design is far from simple and updates may take a considerable time. You also need to guard against malware and hacking. This is a hot topic in the software business, the general opinion is that existing connected car systems are extremely vulnerable to attack which is why many manufacturers including Ford will NOT roll out updates wirelessly.
https://www.information-age.com/connect ... 123464539/

An you imagine the chaos that would ensue if a spoofed update set the speed limit on the A406 to 5 mph or the M1 to 100 mph ?

The update for my Ford SatNav was eventually done by USB stick and took a couple of hours.

At present it is urban areas that are changing fastest as councils roll out 20 mph speed limits. Most rural roads are NSL outside built up areas - see my old friend the B1040.
https://www.google.co.uk/maps/@52.49158 ... 312!8i6656

The speed limit on the A174 has not changed since the road opened in the 1970's but the speed limit on my local urban roads have been up and down like a yoyo.

Last but far from least current car navigation systems are NOT interfaced to the vehicle management system so there is no way a speed limit in the navigation database can set the limiter.
You still don't get it. Stop thinking about what is currently installed in cars and the reliance on private companies.

If it becomes a legal requirement to have the device fitted then the STATE will determine the standards and photocalls used to ensure ALL vehicles are compatible (just as they do with a myriad of other things on motor vehicles already).

If you drop the need for 'instant' speed limit notification (i.e. don't have it reduce form 70mph to 40mph when the VMS on a Smart motorway is activated) then updates can occur at ANY TIME* thus minimising issues that can occur with a lack of coverage.

An active speed limiter would thus be a NEW stated backed system - not a bodged Garmin, Tom Tom / Ford system as fitted to cars today. Updates would be provided by the VOSA and fed into an 'industry standard' black box which uses a combination of GPS and road data to determine the maximum limit. An internal calender would ensure that where limits change the new limit would not apply until the 'start date' was reached.

Finally it should be noted that we are talking about a speed limiter here! Its a fact that very few roads have limits that go up - they mostly go down so the chances of being artificiality kept below the legal limit is going to rare. Moreover if the limit changes to a lower one, it is still up to the driver to respond - saying "but my speed limiter didn't kick in is NOT a satisfactory defence. The whole point of such a system being that it is a backup safety system which should never actually have to be activated if drivers obey the posted limit. (Note, things like airbags are not designed to be routinely used so the principle of having things installed for safety but not normally used already happens).

* If a road authority wishes to permanently reduce the speed limit I believe it has to arrange for a TRO to be published, consulted on and then only enacted after sufficient notice has been given. In other words it takes weeks - if not months (the time frame can of course be extended if necessary) - plenty of time to allow cars to update themselves with the new restrictions ready for the exact date it goes live.
The state can't even turn up on time for its own press briefings and you're trusting it with this?
Bryn
Terminally cynical, unimpressed, and nearly Middle Age already.
She said life was like a motorway; dull, grey, and long.

Blog - https://showmeasign.online/
X - https://twitter.com/ShowMeASignBryn
YouTube - https://www.youtube.com/@BrynBuck
User avatar
Big L
Deputy Site Manager
Posts: 7517
Joined: Sun Nov 14, 2010 20:36
Location: B5012

Re: Westminster 20 limit

Post by Big L »

Bryn666 wrote: Sat Oct 31, 2020 18:46 The state can't even turn up on time for its own press briefings and you're trusting it with this?
He must've forgotten the rugby was on when the schedule was announced.
Make poetry history.

Did you know there's more to SABRE than just the Forums?
Help with maps using the new online calibrator.
Add your roads knowledge to the SABRE Wiki.
Bomag
Member
Posts: 948
Joined: Tue Jan 26, 2010 23:26

Re: Westminster 20 limit

Post by Bomag »

Phil wrote: Sat Oct 31, 2020 18:39
KeithW wrote: Sat Oct 31, 2020 14:05
Phil wrote: Fri Oct 30, 2020 17:28
Firstly, the Internet requires a large quantity of information to be sent as well as received. A freeview set top box only needs to receive information (one way communication) to work (unless you want to use interactive services) and thats precisely why updates can be done in the same way as TV broadcasts.

Secondly the, quantity of data required to update a speed limit data is tiny in comparison to TV services, moreover the loss of signal is not a problem if the database is stored in the vehicle with the only reason to receive broadcast information being to update the information every few weeks*. You do not need large directional areas for this - a standard radio aerial would be sufficient and the update information can be broadcast in exactly the same way as Absolute, Kiss, Virgin, or BBC local radio are!

Thirdly free view boxes are only 'proprietary' because of the 'operating system' they use to run themselves. TV broadcast signals MUST fall into a specific Government mandated frequency spectrum while the MPEG encoding used is an agreed industry standard and does not vary between manufacturers. In effect the ONLY thing that makes each box different is its operating system - and just as Sky used to provide boxes by multiple manufacturers yet all running the same software, the same is perfectly true of a state mandated speed limit system.


* By excluding things like Variable speed limits etc there is no requirement to have a 'live' feed. Most KSI incidents occur in urban areas or rural roads where speed limits do not change for years on end.



The only requirement is that actuall changes to speed limits are properly planned so as to ensure there are a couple of months between the order being made and the date it comes force Just as Windows or your set top box will advise you of an update and give you the choice of applying it when you turn your device off, so it is that a speed limit system could download a new copy of the data base at any time - but only install it when you start your car.


Noe of which alters the fact that you are not updating a single device. Such a system needs to be able to simultaneously roll out updates to a large number of vehicles and do so without disrupting the operation of vehicles that may be doing 70 mph down a motorway at the time. Having loaded new map configurations into an automotive GPS system I have to tell you that the files are large. Moreover a check would have to be run to ensure the downloaded data was valid. To make matters worse there is no common format for this data. GPS updates from Gsrmin dont work for a TomTom system. As for freeview boxes the bandwidth for the TV/Sound payload data is high but that for metadata is low so typically at best you will get a notification that new channels are available which requires the user to initiate a retune.

A better analogy than freeview channel updates is operating system software updates such as IOS and Windows. For such a system at the very least you need a checksum authentication that the download was accurate and the ability to roll back. Real time software design is far from simple and updates may take a considerable time. You also need to guard against malware and hacking. This is a hot topic in the software business, the general opinion is that existing connected car systems are extremely vulnerable to attack which is why many manufacturers including Ford will NOT roll out updates wirelessly.
https://www.information-age.com/connect ... 123464539/

An you imagine the chaos that would ensue if a spoofed update set the speed limit on the A406 to 5 mph or the M1 to 100 mph ?

The update for my Ford SatNav was eventually done by USB stick and took a couple of hours.

At present it is urban areas that are changing fastest as councils roll out 20 mph speed limits. Most rural roads are NSL outside built up areas - see my old friend the B1040.
https://www.google.co.uk/maps/@52.49158 ... 312!8i6656

The speed limit on the A174 has not changed since the road opened in the 1970's but the speed limit on my local urban roads have been up and down like a yoyo.

Last but far from least current car navigation systems are NOT interfaced to the vehicle management system so there is no way a speed limit in the navigation database can set the limiter.
You still don't get it. Stop thinking about what is currently installed in cars and the reliance on private companies.

If it becomes a legal requirement to have the device fitted then the STATE will determine the standards and photocalls used to ensure ALL vehicles are compatible (just as they do with a myriad of other things on motor vehicles already).

If you drop the need for 'instant' speed limit notification (i.e. don't have it reduce form 70mph to 40mph when the VMS on a Smart motorway is activated) then updates can occur at ANY TIME* thus minimising issues that can occur with a lack of coverage.

An active speed limiter would thus be a NEW stated backed system - not a bodged Garmin, Tom Tom / Ford system as fitted to cars today. Updates would be provided by the VOSA and fed into an 'industry standard' black box which uses a combination of GPS and road data to determine the maximum limit. An internal calender would ensure that where limits change the new limit would not apply until the 'start date' was reached.

Finally it should be noted that we are talking about a speed limiter here! Its a fact that very few roads have limits that go up - they mostly go down so the chances of being artificiality kept below the legal limit is going to rare. Moreover if the limit changes to a lower one, it is still up to the driver to respond - saying "but my speed limiter didn't kick in is NOT a satisfactory defence. The whole point of such a system being that it is a backup safety system which should never actually have to be activated if drivers obey the posted limit. (Note, things like airbags are not designed to be routinely used so the principle of having things installed for safety but not normally used already happens).

* If a road authority wishes to permanently reduce the speed limit I believe it has to arrange for a TRO to be published, consulted on and then only enacted after sufficient notice has been given. In other words it takes weeks - if not months (the time frame can of course be extended if necessary) - plenty of time to allow cars to update themselves with the new restrictions ready for the exact date it goes live.
You are missing the point that the UK cannot unilaterally set these requirements without leaving CEN, which would make leaving the EU seem simple, as these standards are coved by CEN Mandates. Neither the UK mirrors of TC301 (automotive) or TC278 (ITS) are in a position to develop alternative connectivity standards for what you suggest. Even if we had some standards the reliability of the data needed for a database for a solely GPS based system is not there, never mind with 'live updates'. Even if the UK wanted to use a sign based system then the abysmal quality of local authority speed limit signing would defeat it (that is not to say that trunk roads are any good). The speed limit signing requirements for temporary limits in TSM Chapter 8 are based on being likely to be sufficiently reliable for in-vehicle systems; for which there is a regular whinge about not allowing the race to the bottom as in Chapter 3. Also DVSA (VOSA ended in 2014) would not touch it with a barge pole, neither would DVLA or VCA. Given the fragmentation of existing policy a England / Wales consortium (+ separate Scotland and NI) would the best you could do, even then there is unlikely to a consensus untill somebody gives LHA a stuff of money even when CEN knocks out a standard.

Also the proposals for ALKS / SAE Level 3+ (for which the consultation finished on the 27th October) do not align with your points.
Phil
Member
Posts: 2271
Joined: Sun Dec 15, 2002 18:03
Location: Burgess Hill,W Sussex, UK

Re: Westminster 20 limit

Post by Phil »

Bomag wrote: You are missing the point that the UK cannot unilaterally set these requirements without leaving CEN, which would make leaving the EU seem simple, as these standards are coved by CEN Mandates. Neither the UK mirrors of TC301 (automotive) or TC278 (ITS) are in a position to develop alternative connectivity standards for what you suggest. Even if we had some standards the reliability of the data needed for a database for a solely GPS based system is not there, never mind with 'live updates'. Even if the UK wanted to use a sign based system then the abysmal quality of local authority speed limit signing would defeat it (that is not to say that trunk roads are any good). The speed limit signing requirements for temporary limits in TSM Chapter 8 are based on being likely to be sufficiently reliable for in-vehicle systems; for which there is a regular whinge about not allowing the race to the bottom as in Chapter 3. Also DVSA (VOSA ended in 2014) would not touch it with a barge pole, neither would DVLA or VCA. Given the fragmentation of existing policy a England / Wales consortium (+ separate Scotland and NI) would the best you could do, even then there is unlikely to a consensus untill somebody gives LHA a stuff of money even when CEN knocks out a standard.

Also the proposals for ALKS / SAE Level 3+ (for which the consultation finished on the 27th October) do not align with your points.
None of the things you mention are impossible (from as technical / engineering perspective) to resolve with enough time, organisational skill or money (whether they are politically acceptable is another thing entirely - and I agree that currently there is not the appetite to embrace them.

For instance, CEN describes itself thus:- CEN is one of three European Standardization Organizations (together with CENELEC and ETSI) that have been officially recognized by the European Union and by the European Free Trade Association (EFTA) as being responsible for developing and defining voluntary standards at European level.

Note the use of the word "voluntary"

In other words if the EU decided to it could easily prescribe a higher standard it could! Governmental organisations are there to govern. A similar situation would apply to UK standards.

Of course there would be howls of protests from commercial interests about 'red tape', 'stifling innovation' and 'Government overreach' but the bottom line is that Governments make the rules, not business.

Similarly what falls under the remit of the DVSA is decided by the UK Government - if they so wished they could task it (and fund it obviously) with creating and maintaining a speed limit database plus provide it with broadcast space to allow it to be consistently sent out from Radio / TV masts across the country.

As for databases - just because one does not exist does not preclude one being created! Again you need to broaden your horizons beyond what currently exists - its perfectly possible to reform the way road records (and speed limits) are kept with centralised databases being built for each nation. Yes it would be time consuming and initially costly, but once built, be easy to keep up to date while also potentially helping highway engineers with their work.

I agree that using roadside signage is useless at present - but again that is the result of poor design and maintenance by the relevant authorities / designers. If improvements were made then it would be a useful backup to any in vehicle database.
Last edited by Big L on Sun Nov 01, 2020 14:09, edited 1 time in total.
Reason: Incorrect author attributed to quote
Bomag
Member
Posts: 948
Joined: Tue Jan 26, 2010 23:26

Re: Westminster 20 limit

Post by Bomag »

Phil wrote: Sat Oct 31, 2020 21:49
Bomag wrote: You are missing the point that the UK cannot unilaterally set these requirements without leaving CEN, which would make leaving the EU seem simple, as these standards are coved by CEN Mandates. Neither the UK mirrors of TC301 (automotive) or TC278 (ITS) are in a position to develop alternative connectivity standards for what you suggest. Even if we had some standards the reliability of the data needed for a database for a solely GPS based system is not there, never mind with 'live updates'. Even if the UK wanted to use a sign based system then the abysmal quality of local authority speed limit signing would defeat it (that is not to say that trunk roads are any good). The speed limit signing requirements for temporary limits in TSM Chapter 8 are based on being likely to be sufficiently reliable for in-vehicle systems; for which there is a regular whinge about not allowing the race to the bottom as in Chapter 3. Also DVSA (VOSA ended in 2014) would not touch it with a barge pole, neither would DVLA or VCA. Given the fragmentation of existing policy a England / Wales consortium (+ separate Scotland and NI) would the best you could do, even then there is unlikely to a consensus untill somebody gives LHA a stuff of money even when CEN knocks out a standard.

Also the proposals for ALKS / SAE Level 3+ (for which the consultation finished on the 27th October) do not align with your points.
None of the things you mention are impossible (from as technical / engineering perspective) to resolve with enough time, organisational skill or money (whether they are politically acceptable is another thing entirely - and I agree that currently there is not the appetite to embrace them.

For instance, CEN describes itself thus:- CEN is one of three European Standardization Organizations (together with CENELEC and ETSI) that have been officially recognized by the European Union and by the European Free Trade Association (EFTA) as being responsible for developing and defining voluntary standards at European level.

Note the use of the word "voluntary"

In other words if the EU decided to it could easily prescribe a higher standard it could! Governmental organisations are there to govern. A similar situation would apply to UK standards.

Of course there would be howls of protests from commercial interests about 'red tape', 'stifling innovation' and 'Government overreach' but the bottom line is that Governments make the rules, not business.

Similarly what falls under the remit of the DVSA is decided by the UK Government - if they so wished they could task it (and fund it obviously) with creating and maintaining a speed limit database plus provide it with broadcast space to allow it to be consistently sent out from Radio / TV masts across the country.

As for databases - just because one does not exist does not preclude one being created! Again you need to broaden your horizons beyond what currently exists - its perfectly possible to reform the way road records (and speed limits) are kept with centralised databases being built for each nation. Yes it would be time consuming and initially costly, but once built, be easy to keep up to date while also potentially helping highway engineers with their work.

I agree that using roadside signage is useless at present - but again that is the result of poor design and maintenance by the relevant authorities / designers. If improvements were made then it would be a useful backup to any in vehicle database.
If you don't understand the difference between harmonised and non-harmonised standards then I really can't help you understand the impact of what you are suggesting. It would make the issue with NI and the withdrawal agreement look minor, even if it was not found to be ultra vires. The issue is, is it practicable not whether its possible. The answer is not within the next five years and unlikely in the next ten (as a comprehensive system). As the chair of the BSI ADAS - infrastructure interaction standards committee just said 'some people on Sabre need a good reality check'
Last edited by Big L on Sun Nov 01, 2020 14:10, edited 1 time in total.
Reason: Incorrect author attributed to quote
Micro The Maniac
Member
Posts: 1175
Joined: Thu Jun 25, 2015 13:14
Location: Gone

Re: Westminster 20 limit

Post by Micro The Maniac »

KeithW wrote: Sat Oct 31, 2020 16:50 If you really want to reduce ksi's on urban roads the answer is to improve the segregation of motorised and non motorised traffic. A large percentage of such incidents are the result of pedestrians stepping into the road without looking or taking a chance on unauthorised crossings. ... An additional hazard is pedestrians using mobile phones when walking and becoming distracted, the highest risk of all is incurred by the alcohol impaired pedestrian aka the drunk wobbling across the road at midnight.
See the recent case of the "zombie pedestrian" (ie preoccupied with her mobile phone) who stepped out in front of a cyclist... the cyclist was found guilty (due to road users having a duty of care!) A clear case of rights needing to be tempered by responsibilities.

I agree with you... we need to safely segregate, and provide appropriate interfaces for crossing - and then the various factions need to have a duty of care to others - which means using their facilities correctly.
AndyB
SABRE Developer
Posts: 11057
Joined: Tue Dec 26, 2006 21:58
Location: Belfast N Ireland
Contact:

Re: Speed Limits under 30MPH

Post by AndyB »

The likelihood is that within the bounds set by the CEN standards or how the EU implements them, there is plenty of room for variation between different manufacturers. In short, we will still have proprietary versions for Garmin, TomTom etc, interpreting the same data in different ways.

The UK government won't deviate very much from any EU implementation if it perceives a risk that car manufacturers will decide not to offer the (high end) models they want in the UK, or if restrictions on what may be placed in a car manufactured in the UK for any market would cause the factory to be closed down.
User avatar
Barkstar
Member
Posts: 2604
Joined: Sun Jul 14, 2013 16:32

Re: Speed Limits under 30MPH

Post by Barkstar »

Helvellyn wrote: Thu Oct 29, 2020 10:38
The intentions behind it all are good (but you know what they say about the road to hell) but personally speaking the effects are making a world I find bloody unpleasant.

Far too often the response to a lack of responsibility in some quarters is to remove it from all. This is insulting and patronising to the majority, and hits the least hard at the people who need to be on the receiving end of it the most (those most likely to ignore and / or work their way around it). It's looking for easy answers.
↑This
Phil wrote: Sat Oct 31, 2020 18:39 Moreover if the limit changes to a lower one, it is still up to the driver to respond - saying "but my speed limiter didn't kick in is NOT a satisfactory defence. The whole point of such a system being that it is a backup safety system which should never actually have to be activated if drivers obey the posted limit.
So if I knowingly go over a limit I get fined. And if the system fouls up and I unknowingly go over the limit I get fined? Lovely. This is all rather too 1984 for me. I'd rather be accused of being a Toad than be a drone thank you.
User avatar
Bryn666
Elected Committee Member
Posts: 35755
Joined: Thu Jun 20, 2002 20:54
Contact:

Re: Speed Limits under 30MPH

Post by Bryn666 »

Barkstar wrote: Sun Nov 01, 2020 12:18
Helvellyn wrote: Thu Oct 29, 2020 10:38
The intentions behind it all are good (but you know what they say about the road to hell) but personally speaking the effects are making a world I find bloody unpleasant.

Far too often the response to a lack of responsibility in some quarters is to remove it from all. This is insulting and patronising to the majority, and hits the least hard at the people who need to be on the receiving end of it the most (those most likely to ignore and / or work their way around it). It's looking for easy answers.
↑This
Phil wrote: Sat Oct 31, 2020 18:39 Moreover if the limit changes to a lower one, it is still up to the driver to respond - saying "but my speed limiter didn't kick in is NOT a satisfactory defence. The whole point of such a system being that it is a backup safety system which should never actually have to be activated if drivers obey the posted limit.
So if I knowingly go over a limit I get fined. And if the system fouls up and I unknowingly go over the limit I get fined? Lovely. This is all rather too 1984 for me. I'd rather be accused of being a Toad than be a drone thank you.
This is why the correct answer to road safety is not to remove the decision making process from people but to enforce rigorous driver training standards and make driving a serious task that only competent people can do.

We now have people who forget to use their windscreen wipers and headlights because the car hasn't done it for them, and we somehow think this dereliction of personal responsibility is an advancement.
Bryn
Terminally cynical, unimpressed, and nearly Middle Age already.
She said life was like a motorway; dull, grey, and long.

Blog - https://showmeasign.online/
X - https://twitter.com/ShowMeASignBryn
YouTube - https://www.youtube.com/@BrynBuck
User avatar
KeithW
Member
Posts: 19205
Joined: Thu Dec 04, 2014 13:25
Location: Marton-In-Cleveland North Yorks

Re: Westminster 20 limit

Post by KeithW »

Phil wrote: Sat Oct 31, 2020 18:39

You still don't get it. Stop thinking about what is currently installed in cars and the reliance on private companies.

If it becomes a legal requirement to have the device fitted then the STATE will determine the standards and photocalls used to ensure ALL vehicles are compatible (just as they do with a myriad of other things on motor vehicles already).

If you drop the need for 'instant' speed limit notification (i.e. don't have it reduce form 70mph to 40mph when the VMS on a Smart motorway is activated) then updates can occur at ANY TIME* thus minimising issues that can occur with a lack of coverage.

An active speed limiter would thus be a NEW stated backed system - not a bodged Garmin, Tom Tom / Ford system as fitted to cars today. Updates would be provided by the VOSA and fed into an 'industry standard' black box which uses a combination of GPS and road data to determine the maximum limit. An internal calender would ensure that where limits change the new limit would not apply until the 'start date' was reached.

Finally it should be noted that we are talking about a speed limiter here! Its a fact that very few roads have limits that go up - they mostly go down so the chances of being artificiality kept below the legal limit is going to rare. Moreover if the limit changes to a lower one, it is still up to the driver to respond - saying "but my speed limiter didn't kick in is NOT a satisfactory defence. The whole point of such a system being that it is a backup safety system which should never actually have to be activated if drivers obey the posted limit. (Note, things like airbags are not designed to be routinely used so the principle of having things installed for safety but not normally used already happens).

* If a road authority wishes to permanently reduce the speed limit I believe it has to arrange for a TRO to be published, consulted on and then only enacted after sufficient notice has been given. In other words it takes weeks - if not months (the time frame can of course be extended if necessary) - plenty of time to allow cars to update themselves with the new restrictions ready for the exact date it goes live.
I am a professional software engineer and know precisely how software development works and I also am well aware of the record on the UK government software projects - it is appalling. The poster boy is the abandoned UK National Program for IT

One of the largest IT project failures of any kind was the UK National Health Service’s attempt to create a national electronic health record system. The project was cancelled in September 2011 after blowing through at least £9.8 billion and having implemented only two percent of the proposed system . It began in 2004 with a projected price tag of £6 billion and was supposed to be completed in 2010. One of the largest health trusts in eastern England is instead using a system that cost less than 1% of the government system and was written by 4 guys working out of a rented office in Cambridge. They did something the government bods never did, sat down with the hospital staff and said 'OK guys tell us what you need it to do ?' and then wrote something to do that without 5 tiers of civil servants all adding their requirements.

The reasons for the plan’s failure involved all the usual suspects, including: significant project changes, excessive use of expensive external contractors, excessive technical complexity , a lack of management realism and ineptitude. At the end of the day it is just a document management system of the sort that can be bought off the shelf and tailored to a specific requirement. Every time the people at Addenbrookes sat down with the developers the system had changed, some bureaucrat had added new features. Worse of the records entered into the new system over 85% were lost, or corrupted. This is the one thing that must NEVER happen.

Now here is a reality check regarding car sales.

The UK is an important market but a small one. In 2019 there were approx 2.7 million new cars registered in the UK. Within the EU and EFTA the figure is around 20 million and globally its more like 65 million. Their no UK owned mass market manufacturer , those operating in the UK are foreign owned, tell Peugeot, Nissan and BMW that they MUST allow the DfT to mandate how their cars are made and designed and they will move production elsewhere.

As to Speed Limiters you seem to misunderstand the basic functionality. The way they work is that a series of sensors detect how fast you're going, then communicate that information to the engine's computer. Once you reach a pre-determined top speed, the computer steps in and restricts the flow of air and fuel to the engine to limit the top speed.

Neither TomTom nor Garmin make speed limiters, the reality is that it is an integral part of design of the engine management.system so I am afraid the DfT cannot simply wave a magic wand and make it so. Real time software design is something of a black art, you have to ensure that the computer never runs out of time processing a change in inputs, showing a spinning 'working' symbol wont cut it if you are accelerating past a truck.

Last but not least a private software developer has to produce the system to a defined specification, demonstrate that it works and is supportable and undertake to fix any problems and indemnify the buyer if necessary. Government IT development groups do none of the above as they have sovereign immunity - the ultimate 'Get out of Jail Free' card.

We all grouse about Windows OS but imagine a version developed in Whitehall - shudders !
User avatar
KeithW
Member
Posts: 19205
Joined: Thu Dec 04, 2014 13:25
Location: Marton-In-Cleveland North Yorks

Re: Westminster 20 limit

Post by KeithW »

Phil wrote: Sat Oct 31, 2020 21:49
Bomag wrote:

You are missing the point that the UK cannot unilaterally set these requirements without leaving CEN, which would make leaving the EU seem simple, as these standards are coved by CEN Mandates. Neither the UK mirrors of TC301 (automotive) or TC278 (ITS) are in a position to develop alternative connectivity standards for what you suggest. Even if we had some standards the reliability of the data needed for a database for a solely GPS based system is not there, never mind with 'live updates'. Even if the UK wanted to use a sign based system then the abysmal quality of local authority speed limit signing would defeat it (that is not to say that trunk roads are any good). The speed limit signing requirements for temporary limits in TSM Chapter 8 are based on being likely to be sufficiently reliable for in-vehicle systems; for which there is a regular whinge about not allowing the race to the bottom as in Chapter 3. Also DVSA (VOSA ended in 2014) would not touch it with a barge pole, neither would DVLA or VCA. Given the fragmentation of existing policy a England / Wales consortium (+ separate Scotland and NI) would the best you could do, even then there is unlikely to a consensus untill somebody gives LHA a stuff of money even when CEN knocks out a standard.

Also the proposals for ALKS / SAE Level 3+ (for which the consultation finished on the 27th October) do not align with your points.
None of the things you mention are impossible (from as technical / engineering perspective) to resolve with enough time, organisational skill or money (whether they are politically acceptable is another thing entirely - and I agree that currently there is not the appetite to embrace them.
Please note - I did NOT write any of this.

Admin note : quoting corrected.
Last edited by Big L on Sun Nov 01, 2020 14:12, edited 1 time in total.
Reason: Incorrect author attributed to quote
User avatar
Barkstar
Member
Posts: 2604
Joined: Sun Jul 14, 2013 16:32

Re: Westminster 20 limit

Post by Barkstar »

KeithW wrote: Sun Nov 01, 2020 13:06
Last but not least a private software developer has to produce the system to a defined specification, demonstrate that it works and is supportable and undertake to fix any problems and indemnify the buyer if necessary. Government IT development groups do none of the above as they have sovereign immunity - the ultimate 'Get out of Jail Free' card.
Even if the current Govt went ahead such a plan, and it withstood subsequent changes of Govt, I should imagine myself and many fellow Sabristi would be passed the ability to drive before it were anywhere near a role out. By which time I'd imagine other events may have overtaken some of the perceived need for such a 'Ministry of Plenty' scheme. Which isn't to say 'go ahead, it won't affect me' but to point out that reliable, safe and complete implementation could take a decade and more even if done by competent companies. And then how long to actually make any measurable changes to road KSI, given all the vehicles running without it for decades after and how few RTC have a single cause that will stand up to scrutiny?

And for those of us who use powered two wheels how would such a system work safely and practically?
User avatar
FosseWay
Assistant Site Manager
Posts: 19621
Joined: Thu Feb 23, 2006 22:26
Location: Gothenburg, Sweden

Re: Speed Limits under 30MPH

Post by FosseWay »

Bryn666 wrote: Sun Nov 01, 2020 12:59 This is why the correct answer to road safety is not to remove the decision making process from people but to enforce rigorous driver training standards and make driving a serious task that only competent people can do.
This. And I'd extend that line of reasoning to the calls for more segregation above, as well. The "concrete jungle" school of urban planning from the 1960s was all about segregation - you had urban motorways and other main roads that were safe for pedestrians because the latter were not allowed there, being siphoned off through concrete underpasses where they got mugged instead, or being told to take long alternative routes or use steps when they couldn't, so they didn't go where they wanted to at all.

Segregation is beneficial in some circumstances and not in others. There are highways designed for fast traffic that it is sensible to dissuade or prevent cyclists and pedestrians from using, for example. But one of the recurring themes in this thread is the unsuitability of applying blanket policies to diverse situations, whether it's blanket 20 limits, blanket rules on where you're (not) allowed to walk, cycle or drive, or blanket policies such as "segregate motor and pedestrian traffic as much as possible". KeithW mentions quite rightly that part of the KSI picture is made up by pedestrians who do something daft. We need to address *those* pedestrians, not just say to all pedestrians that none of them are capable of interacting with traffic and that therefore all roadways must either be banned for pedestrians or banned for traffic.

There's a planning consultation going on in my area, where the council have identified a few locations for new housing. As it happens, they also say that the existing road network is broadly capable of absorbing the extra traffic expected from the proposed number of new houses, but they justify the relatively low number of possible new houses partly by arguing that the road network would need to be changed if there were significantly more new houses. For those new houses that are allowed, they will still look at whether the roads need changing with a view to adding pavements or cycle paths in some places. This is where I think they are going over the top, and we're back to the segregation question again. The roads in question are all limited to 30 km/h. They are a mixture of narrow S2 and S1 with passing places. They have both active traffic calming in the form of humps and natural features like blind bends that encourage lower speeds. None of the roads are through routes to anywhere (the area is like the veins of a leaf, with all routes ultimately being cul-de-sacs). Any changes would necessitate straightening curves and blasting (or at least clearing established vegetation) to widen the roadway in order to insert a pavement; that pavement would then be labelled a shared-use ped/cycle path but not have the dimensions to satisfy both modes at once. Such invasive intervention would negatively affect the character of the area and disrupt the natural environment more than the new houses themselves will.

Basically, the whole point of residential roads with low speed limits, traffic calming and so on is that all of us can use them together without needing a lot of invasive urban infrastructure. I don't think we do ourselves any favours by saying to people that they're not trusted to walk or cycle on a residential road with a 30 km/h limit unless it has a pavement, airport runway lighting, railings and GKW else.
Did you know there's more to SABRE than just the Forums?
Add your roads knowledge to the SABRE Wiki today!
Have you browsed SABRE Maps recently? Try getting involved!
Post Reply