Speed limiters in cars

[skyhigh]

It might not have made it through the fence though..

Even at 30mph a 2 ton Range Rover still has an awful lot of energy behind it

 

[185]

Imagine if UK roads had Railway TPWS fitted.... emergency brake applications.... every windscreen in the country would be cracked within the hour.

 

[richw]

Anyone who uses gps regularly will know that it wanders and places in the wrong place therefore at present wouldn’t be a suitable system

 

[AM9]

Imagine if UK roads had Railway TPWS fitted.... emergency brake applications.... every windscreen in the country would be cracked within the hour.

Why would an emergency brake application crack a car windscreen?

 

[alxndr]

Why would an emergency brake application crack a car windscreen?

Presumably through people and/or things flying through it due to the rapid deceleration.

 

[AM9]

Presumably through people and/or things flying through it due to the rapid deceleration.

Unless it was an unbelted driver/passenger, (which would tend to be a salutory lesson to belt up), - there aren't that many owners stupid enough to have loose clutter located where a heavy brake application would turn it into a laminated glass piercing missile.

 

[Meerkat]

Anyone who uses gps regularly will know that it wanders and places in the wrong place therefore at present wouldn’t be a suitable system

Mine takes a fair while to realise that I have ignored its advice and stayed on the motorway - I wouldn’t want it killing the power because it thinks I had hit the 30 limit on the slip road!

 

[CarltonA]

What car is that? So I can avoid it whilst looking for my new one......

It's a KIA , I think the settings can be changed on the screen. I've not bothered to try changing anything tbh.

 

[Chester1]

I think its very clear that variable speed limiters in vehicles are not sufficiently reliable. Its surprising that all new cars made or imported into UK are not limited to 79mph. The number of company vehicles that have limiters installed shows it would be straightforward and cheap to implement. In long term an upgraded licence could be required to drive a car without a limiter for use on track days etc. The ability to drive at extremely high speeds isn't a God given right and should be quickly revoked if drivers commit offences. 79mph would mean people wouldn't get fined for accidentally exceeding limit on motorway and allow them to go full speed if they take their car to the continent.

 

[Bletchleyite]

I think its very clear that variable speed limiters in vehicles are not sufficiently reliable. Its surprising that all new cars made or imported into UK are not limited to 79mph. The number of company vehicles that have limiters installed shows it would be straightforward and cheap to implement. In long term an upgraded licence could be required to drive a car without a limiter for use on track days etc. The ability to drive at extremely high speeds isn't a God given right and should be quickly revoked if drivers commit offences. 79mph would mean people wouldn't get fined for accidentally exceeding limit on motorway and allow them to go full speed if they take their car to the continent.

Given that most speed enforcement uses 10% + 2mph or similar, and given that the speedo will over-read by a few percent as well, it really would take an incredibly incompetent driver to accidentally get caught for speeding on a motorway with the 70 limit in place.

These days with "smart motorways" the norm, the excessive speeding you used to see (90mph+) is in my experience rather rare. The prevailing speed on most motorways these days seems to be between 65mph and about 80mph at most.

 

[Chester1]

Given that most speed enforcement uses 10% + 2mph or similar, and given that the speedo will over-read by a few percent as well, it really would take an incredibly incompetent driver to accidentally get caught for speeding on a motorway with the 70 limit in place.

These days with "smart motorways" the norm, the excessive speeding you used to see (90mph+) is in my experience rather rare. The prevailing speed on most motorways these days seems to be between 65mph and about 80mph at most.

I am really thinking of the perspective of neutralising arguments against limiters in general. If the government proposed mandatory limiters then the would be tons of "what about x" arguments against it. The ability to do ~130kph abroad is a reasonable argument against 70mph limiters. The key would be establishing a limit, even if considerably above 70mph. It might be rarer these days but idiots driving at 90mph, 100mph etc still happens and its astounding that most of the population can legally drive a car capable of traveling at double the national speed limit. With our attitude to safety in almost every other aspect of life its a relic.

 

[Domh245]

Given that most speed enforcement uses 10% + 2mph or similar, and given that the speedo will over-read by a few percent as well, it really would take an incredibly incompetent driver to accidentally get caught for speeding on a motorway with the 70 limit in place.

It isn't about getting caught, it's about preventing speeding (especially on the motorways without any cameras - M40 particularly comes to mind!)

I have to agree, despite being a bit of a car nut and former 'speed enthusiast', there's no reason for a car on a public UK road to be going above 80mph*, and there's not much reason not to have a limiter set accordingly

*it gives you a bit of wriggle room for speeding if you want to get an overtake done/done quicker, but with a 70mph speed limit that ought to be the maximum speed you do under normal circumstances. Cruising continuously at 80 really isn't on

 

[Meerkat]

Cruising continuously at 80 really isn't on

Why not? How much more dangerous is that than at 70?
if we have physically limited speeds why not make it 80?

 

[the sniper]

Why not? How much more dangerous is that than at 70?
if we have physically limited speeds why not make it 80?

SHAME! SHAME! SHAME!

Who needs to do more than 68mph over Shap on the M6? That's just about enough to get you past the old Subaru Forester on the adjacent single track lane...

 

[Domh245]

Why not? How much more dangerous is that than at 70?
if we have physically limited speeds why not make it 80?

Because current speed limit is 70? I suppose that is a fairly important caveat. If the speed limit were 80 then rather obviously cruising at 80mph would be fine, but it isn't, so it's not.

I'll grant you that 80mph is not particularly more dangerous than 70mph for anyone in a modern vehicle, but on the other side 70mph results in lower emissions, gives increased (notional) capacity, and reduces the speed differential between lorries and (almost) everything else. I suppose the usefulness of 80mph also depends on what sort of driving you do, my normal London-Manchester route I'd save up to 22 minutes (against journey time of 3:44) if every bit of road (and link road) that's currently 70mph went to 80mph. Equally I'd save all of 5 minutes on a journey down to the south coast (1:37). On some of my previous drives down to the Tolouse area, I've been quite glad that the French autoroutes are 130kph!

 

[Bald Rick]

These days with "smart motorways" the norm, the excessive speeding you used to see (90mph+) is in my experience rather rare. The prevailing speed on most motorways these days seems to be between 65mph and about 80mph at most.

Give eitherthe M40 or the M6 north of Preston a go on a Sunday evening...

 

[JohnMcL7]

Mandatory speed limiters are coming I believe:

EU ruling means speed limiters will be mandatory in the UK by 2022 | RAC Drive

www.rac.co.uk

I was watching a video of the new Tesla Model S Plaid in its high speed launch mode where the car went from 0-165mph complete with a fancy dash animation which was being done on a public road and th driver almost lost control of the car. It feels irresonsponsible to allow such a mode on any road rather than restricting it to race tracks or just not on public roads.

 

[Meerkat]

I would be less annoyed by this if the speed limits weren’t so ridiculously low, and continuously getting lower despite cars getting safer

 

[apk55]

I could well see that in a few years after their introduction that insurance companies give a discount for driving one if they prove to be safer and make it almost impossible to get insurance on on none fitted car unless they have a long NCD and a clean license or have a GPS tachograph fitted.

 

[philthetube]

I have to wonder then what the actual point of such a system would be. In my local area the road which must have the highest amount of speeding is a few miles of 50mph dual carriageway, sandwiched by 30 miles plus of a continuous 70mph limit. (The road itself doesn't change in quality, but has a lower speed limit as that section is through a town and has substandard short sliproads) On this road invariably the left lane is doing exactly 50mph, the right lane for those ignoring the limit and doing 60 plus. Your system would prevent few from speeding there, but would make it considerably more dangerous.

Never going to be perfect but would prevent idiots driving all over the place at excess speed, but even better, make it much easier for the police to catch criminals, particularly car thieves if they could only run away at 30 mph

 

[87 027]

Never going to be perfect but would prevent idiots driving all over the place at excess speed, but even better, make it much easier for the police to catch criminals, particularly car thieves if they could only run away at 30 mph

Only if the system doesn't have a driver override! Which as has been said upthread in itself brings a whole load of potential safety issues, not to mention accountability and liability if such a system is shown to be a contributory factor in an accident (e.g. loss of power when acceleration could have got you out of trouble).

Trackers already exist that can disable vehicles reported as stolen, although there is the potential for cyber attack

Disabling Cars by Remote Control - Schneier on Security

www.schneier.com

And more recently a 'white hat hacker' gained control over the entire fleet of Teslas

The Big Tesla Hack: A hacker gained control over the entire fleet, but fortunately he's a good guy

A few years ago, a hacker managed to exploit vulnerabilities in Tesla’s servers to gain access and control over the...

electrek.co

In the next 10-20 years, when positioning technology and autonomous driving have advanced in leaps and bounds, the picture could well be different and technology could provide a more failsafe solution.

 

[gimmea50anyday]

If people are considering such ideas then rather than having a variable speed limiter deciding which road you are on, as there are too many variables with location, time, weather, GPS accuracy etc, why not simply set an undefeatable upper speed limit within the cars engine management system and make its operation part of the MOT? say an absolute limit of 85mph which simply drops the throttle if you exceed that speed. Works in exactly the same way the speed limiter within the cruise control settings works except this is mandatory and not voluntary.

Personally I dont want a car deciding for me what speed I am allowed to go, or when to turn the lights on or dip them, or how fast the wipers should move or steering for me when it thinks I'm in the wrong lane. I want to be in control. Automation for convenience is making drivers lazy, relying on the always on courtesy lights for example and not turning the cars lights on in poor weather or at dusk for example. The benefits of lane assist, cruise control and speed limiters cannot be ignored but as has already been demonstrated Autonomous trains is a leap in faith in technology too far for practicality yet we are still pushing for autonomous cars step by step....

 

[JohnMcL7]

If people are considering such ideas then rather than having a variable speed limiter deciding which road you are on, as there are too many variables with location, time, weather, GPS accuracy etc, why not simply set an undefeatable upper speed limit within the cars engine management system and make its operation part of the MOT? say an absolute limit of 85mph which simply drops the throttle if you exceed that speed. Works in exactly the same way the speed limiter within the cruise control settings works except this is mandatory and not voluntary.

The obvious problem with an undefeatable limit system is that there are places where there are no speed limit such as race tracks where I've taken my car and plan to do so again, plenty of others do the same with road legal cars.

 

[AM9]

The obvious problem with an undefeatable limit system is that there are places where there are no speed limit such as race tracks where I've taken my car and plan to do so again, plenty of others do the same with road legal cars.

There should be a legally defined transition when a vehicle is moved off the public highway and into an uncontrolled area. There are many aspects of vehicle performance that would make a track-ready car non-compliant with the Construction and Use regulations. That would include emissions, noise levels, tyre specifications and conditions. If a non-defeatable speed governor was fitted, there could be a formal process to disable it, with a visible indicator. There should also be a non-erasable GPS time stamped electronic log onboard of any locations where the vehicle had been run in that condition. The process should have a similar legal weight to the SORN rules, as the vehicle keeper would effectively be removing the vehicle from public highway use eligibility.

 

[gimmea50anyday]

Realistically it wouldn't work. Having a fixed upper speed limit won't eliminate the problem of a motorist blasting along at 60 passed a school at chuckout time. SatNavs regularly demonstrate GPS isn't reliably accurate enough to enforce speed limits and may well kick in at a moment that actually puts a road user in danger such as during an overtaking maneuver, or to avoid a collision. Besides, pool cars would simply have the limiter bypassed. They aren't taxed or insured and won't be road legal for a number of reasons so a speed limiter being defeated isn't going to make any difference...

 

[61653 HTAFC]

I must admit, when I first started to drive (or rather once I'd been driving a few months and was a bit more confidence) I would regularly cruise at 80mph on quieter motorways when conditions allowed. After all, petrol was only 72.9p a litre. Nowadays I wouldn't dream of doing so, not just because detection is more automated and more widespread, but because with fuel costs having pretty much doubled, it isn't worth it.

So no need to spend millions on R&D to improve GPS or fit balises every 50yds, nor to continue to feed the ego of the world's greatest vapourware salesman.

 

[AM9]

Realistically it wouldn't work. Having a fixed upper speed limit won't eliminate the problem of a motorist blasting along at 60 passed a school at chuckout time. SatNavs regularly demonstrate GPS isn't reliably accurate enough to enforce speed limits and may well kick in at a moment that actually puts a road user in danger such as during an overtaking maneuver, or to avoid a collision. Besides, pool cars would simply have the limiter bypassed. They aren't taxed or insured and won't be road legal for a number of reasons so a speed limiter being defeated isn't going to make any difference...

I wasn't suggesting that GPS is used to detect a speed limit. I was saying that is a speed limiter was disabled (e.g. so that the vehicle could be driven at speed on a race track), GPS could confirm that it was in such a location.

I must admit, when I first started to drive (or rather once I'd been driving a few months and was a bit more confidence) I would regularly cruise at 80mph on quieter motorways when conditions allowed. After all, petrol was only 72.9p a litre. Nowadays I wouldn't dream of doing so, not just because detection is more automated and more widespread, but because with fuel costs having pretty much doubled, it isn't worth it.

So no need to spend millions on R&D to improve GPS or fit balises every 50yds, nor to continue to feed the ego of the world's greatest vapourware salesman.

I too used to exceed the 70mph speed limit in the few years after passing the test when I was driving cars hired by employers, - I didn't care how much fuel costed.
When I drive now the cost of fuel is irrelevant to me but the real incentive to drive safely is that I no longer have an irresponsible selfish attitude to the safety of others; nor do I see my or anybody else's self importance an excuse to break a perfectly observable law.

 

[johncrossley]

Do the many vehicles that already have speed limiters cause problems with safety that outweigh the benefit? For example HGVs limited at 56 mph and coaches limited at 62 mph. Some London buses have speed limiters that can adjust automatically to 20 mph and 30 mph zones. Are these dangerous?

 

[87 027]

A bus adjusting to 20/30 mph in an urban location isn’t the same as having the power cut out when, say, overtaking a tractor or caravan on a single carriageway road.

 

[AM9]

A bus adjusting to 20/30 mph in an urban location isn’t the same as having the power cut out when, say, overtaking a tractor or caravan on a single carriageway road.

It would certainly help some car drivers to learn when not to overtake tractors or caravans, and just wait a while.