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PostPosted: Tue Dec 30, 2008 8:43 pm
by fungus
I certainly wont be volunteering to have one fitted.

This is yet another example of the Governments misguided obsession with limiting speed as their main weapon in the fight to make the roads safer. It's only through educating all road users that an improvement will be seen.

A few weeks ago I was driving on a lightly trafficked residential road, 30 mph limit. Ahead of me was a car signaling to turn right into a junction ahead. The approach had a hatched off area to protect right turning vehicles. As the car ahead filtered into the right turn lane I filtered past on the left. There was a car in the road to the right waiting to emerge right. As I drew parallel to the car in front that was turning right, the car waiting to emerge pulled out very quickly, I can only assume that the driver in front who was turning right had flashed him out. Braking was not an option (I was too close), the emerging driver would have hit the front O S. of my car. I opted to accelerate out of trouble. If my car had been limited, I would not have been able to avoid a collision. After accelerating out of trouble I then had to brake because I was now traveling at about 40mph and there was a speed camera ahead.

This incident has confirmed what I have always believed, that the driver must have ultimate control of the vehicle, not a device that limits the drivers ability to act appropriately.

Nigel ADI
IAM trainee observer

PostPosted: Tue Dec 30, 2008 9:41 pm
by daz6215
Funny i was under the impression that most incidents occurred in roads under 40 mph, at lower speeds. :?

PostPosted: Wed Dec 31, 2008 12:00 am
by MGF
fungus wrote:As I drew parallel to the car in front that was turning right, the car waiting to emerge pulled out very quickly, I can only assume that the driver in front who was turning right had flashed him out. Braking was not an option (I was too close), the emerging driver would have hit the front O S. of my car. I opted to accelerate out of trouble. If my car had been limited, I would not have been able to avoid a collision. After accelerating out of trouble I then had to brake because I was now traveling at about 40mph and there was a speed camera ahead.

This incident has confirmed what I have always believed, that the driver must have ultimate control of the vehicle, not a device that limits the drivers ability to act appropriately.


If you were exercising 'ultimate control' how come you didn't anticipate the car pulling out in front of you and adjust your speed accordingly?

I agree, because you had approached the hazard too fast your instinctive reaction was to to accelerate. Perhaps these systems should have an over-ride where if you floor the accelerator pedal you will get instant but temporary acceleration.

PostPosted: Wed Dec 31, 2008 10:05 am
by spurs-442
MGF wrote:
fungus wrote:As I drew parallel to the car in front that was turning right, the car waiting to emerge pulled out very quickly, I can only assume that the driver in front who was turning right had flashed him out. Braking was not an option (I was too close), the emerging driver would have hit the front O S. of my car. I opted to accelerate out of trouble. If my car had been limited, I would not have been able to avoid a collision. After accelerating out of trouble I then had to brake because I was now traveling at about 40mph and there was a speed camera ahead.

This incident has confirmed what I have always believed, that the driver must have ultimate control of the vehicle, not a device that limits the drivers ability to act appropriately.


If you were exercising 'ultimate control' how come you didn't anticipate the car pulling out in front of you and adjust your speed accordingly?

I agree, because you had approached the hazard too fast your instinctive reaction was to to accelerate. Perhaps these systems should have an over-ride where if you floor the accelerator pedal you will get instant but temporary acceleration.


The question then becomes - what is temporary?

The only place i can see this working is on the motorway where a limit of 75-80mph is applied (thus allowing overtaking to occur safely) a bit like cruise control.

PostPosted: Wed Dec 31, 2008 12:33 pm
by ExadiNigel
spurs-442 wrote:....

The question then becomes - what is temporary?


Something that isn't permanent? I think the suggestion was something that could work a little like kick-down on an auto. Similar also to the speed limiters installed on the Mercs.

spurs-442 wrote:The only place i can see this working is on the motorway where a limit of 75-80mph is applied (thus allowing overtaking to occur safely) a bit like cruise control.


I seem to remember the limit on the motorway as being 70. Where does the 75 - 80 come from? I find I can overtake perfectly safely at 70. If you find the necessity to take your speed up to 75-80 then perhaps you are forgetting to ask your self a couple of questions -

- Is it legal?
- Is it necessary?

Nigel

PostPosted: Wed Dec 31, 2008 1:19 pm
by daz6215
If everyone was limited to 70mph it would cause chaos, in effect you would have the same problems happening to cars that now happen to LGV's at 56mph, people trying to get part each other doing 0.5 mph different to the vehicle they want to be passed. Add in there variations of incline and weight of vehicles and loads etc ,mmmm! i can just imagine! :lol:

PostPosted: Wed Dec 31, 2008 1:22 pm
by Big Err
daz6215 wrote:If everyone was limited to 70mph it would cause chaos,


Not sure on that. The reason two HGVs passing each other at 56mph and 56.5mph creates an issue is that everyone else in cars can do 70mph.

Take a look at areas with average speed cameras in operation, the traffic flows ok with high occupancy in all lanes and not much chaos and that's where most vehicles are running with a speed difference of only a couple of mph.

PostPosted: Wed Dec 31, 2008 1:28 pm
by daz6215
Big Err wrote:
daz6215 wrote:If everyone was limited to 70mph it would cause chaos,


Not sure on that. The reason two HGVs passing each other at 56mph and 56.5mph creates an issue is that everyone else in cars can do 70mph.

Take a look at areas with average speed cameras in operation, the traffic flows ok with high occupancy in all lanes and not much chaos and that's where most vehicles are running with a speed difference of only a couple of mph.


Yeah i would agree and i can see your point, but one of the singlest biggest things that LGV's do as a result of limiting is tailgate one another, if this technology were fitted to cars it would be pandamoniam, just my opinion of course.

PostPosted: Wed Dec 31, 2008 1:33 pm
by Big Err
daz6215 wrote:Yeah i would agree and i can see your point, but one of the singlest biggest things that LGV's do as a result of limiting is tailgate one another, if this technology were fitted to cars it would be pandamoniam, just my opinion of course.


It's the threat of a ticket that controls the driver behaviour at average speed camera, and yes I agree with the tailgaiting. You see it with people who currently drive with cruise control on - no use of acceleration sense.

PostPosted: Wed Dec 31, 2008 1:35 pm
by michael769
Big Err wrote:
daz6215 wrote:If everyone was limited to 70mph it would cause chaos,


Not sure on that. The reason two HGVs passing each other at 56mph and 56.5mph creates an issue is that everyone else in cars can do 70mph.



You presume there won't be anything doing more that 70. There will of course - any emergency vehicle. What do they do when you have to deal with two long streams of cars on a two lane motorway or dual carriageway one doing 69.2 and the other doing 69.9?

PostPosted: Wed Dec 31, 2008 1:44 pm
by Big Err
michael769 wrote:You presume there won't be anything doing more that 70. There will of course - any emergency vehicle. What do they do when you have to deal with two long streams of cars on a two lane motorway or dual carriageway one doing 69.2 and the other doing 69.9?


I'd suspect it would be dealt with the same way as the emergency serices do with any other congested part of network - a daily occurence.

PostPosted: Wed Dec 31, 2008 2:18 pm
by vonhosen
Big Err wrote:
daz6215 wrote:Yeah i would agree and i can see your point, but one of the singlest biggest things that LGV's do as a result of limiting is tailgate one another, if this technology were fitted to cars it would be pandamoniam, just my opinion of course.


It's the threat of a ticket that controls the driver behaviour at average speed camera, and yes I agree with the tailgaiting. You see it with people who currently drive with cruise control on - no use of acceleration sense.


No, you see it with some not all.
The cruise control use isn't the problem, it's the attitude of the driver that is.
In years to come no doubt vehicle spacing will be managed by technology rather than the driver.

PostPosted: Wed Dec 31, 2008 2:31 pm
by Darren
vonhosen wrote:In years to come no doubt vehicle spacing will be managed by technology rather than the driver.


One of my customers develops exactly this type of technology.

PostPosted: Wed Dec 31, 2008 2:41 pm
by michael769
daz6215 wrote:Funny i was under the impression that most incidents occurred in roads under 40 mph, at lower speeds. :?


You are correct in terms of collisions. However the government's focus is not on collision reduction but casualty reductions.

I understand that most fatalities and very serious injuries involve speeds higher than 40mph.

PostPosted: Wed Dec 31, 2008 2:46 pm
by jont
Darren wrote:
vonhosen wrote:In years to come no doubt vehicle spacing will be managed by technology rather than the driver.

One of my customers develops exactly this type of technology.

I thought Jagaur and Mercedes (possibly among others) already had demonstrated radar cruise control which includes slowing down to maintain a gap from the car in front, and Volvo has recently announced a low speed collision avoidance system (eg the typical roundabout entry bump).