Intelligent Speed Assistance
#126
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You can easily demonstrate how well we can and do control vehicle speeds to what we want by observing how well the typical driver is at maintaining their speed just under the understood local "fudge factor. We are dnag near experts at it. We could be just as expert at keeping our speed just under the posted speed limit. It's a mindset and a choice, not a practical necessity.
Last edited by Jay Turberville; 12-21-23 at 01:27 PM.
#127
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My observation is that cars and bicycles will both routinely roll stops when
1) it is obvious and clear that there is no cross traffic
2) they are not intersecting a faster and more major thoroughfare.
Someday I'll put a video camera up at a typical local stop and gather some stats on it. My bet is that 2/3rds of the drivers will roll the stop when they are alone.
I think it is actually safer and more expeditions for cyclists to treat stop signs as yield signs. That helps them clear the intersection quickly and is still quite safe. Some cities (apparently yours) have realized this and have changed regulations accordingly.
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#128
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For practical purposes there has to be a tolerance on the posted limit for prosecution. Here that tolerance is 10% +2 mph. So in a 30 limit, you get prosecuted at 35. That tolerance allows for the combined error in vehicle indicated speed and camera measured speed. So if you drove at an indicated 30, there would be practically no chance of getting a ticket in error. But if you chose to drive at an indicated 34 then you might get a ticket if your speedometer or camera calibration was slightly out. We could argue about how generous the 10% +2 tolerance is, but it seems reasonable to me and has been very widely adopted by UK police forces.
I agree that active mandatory vehicle speed control would not work unless retro-fitted to all vehicles, which is impractical. It would also cause traffic issues on motorways as it already does to some extent with HGV limiters, where you get one lorry attempting to pass another with a speed differential of 0.1 mph, blocking the lane for literally minutes while they crawl past on the speed limiter.
I agree that active mandatory vehicle speed control would not work unless retro-fitted to all vehicles, which is impractical. It would also cause traffic issues on motorways as it already does to some extent with HGV limiters, where you get one lorry attempting to pass another with a speed differential of 0.1 mph, blocking the lane for literally minutes while they crawl past on the speed limiter.
The studies I've seen suggest that traffic violations are about equal between cars and bicycles.
My observation is that cars and bicycles will both routinely roll stops when
1) it is obvious and clear that there is no cross traffic
2) they are not intersecting a faster and more major thoroughfare.
Someday I'll put a video camera up at a typical local stop and gather some stats on it. My bet is that 2/3rds of the drivers will roll the stop when they are alone.
I think it is actually safer and more expeditions for cyclists to treat stop signs as yield signs. That helps them clear the intersection quickly and is still quite safe. Some cities (apparently yours) have realized this and have changed regulations accordingly.
My observation is that cars and bicycles will both routinely roll stops when
1) it is obvious and clear that there is no cross traffic
2) they are not intersecting a faster and more major thoroughfare.
Someday I'll put a video camera up at a typical local stop and gather some stats on it. My bet is that 2/3rds of the drivers will roll the stop when they are alone.
I think it is actually safer and more expeditions for cyclists to treat stop signs as yield signs. That helps them clear the intersection quickly and is still quite safe. Some cities (apparently yours) have realized this and have changed regulations accordingly.
#129
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I don't keep stats, but these things are common. And even if I did keep stats, we'd have to have a discussion on how to evaluate them since there are many more cars than bicycles.
As mentioned by someone else, the key thing isn't which group breaks traffic laws more often. They both do it a lot. The key thing is which group does the most damage - especially to others.
#130
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Nonsense.. What you describe is a social convention and a holdover from decades past. The precision at which we can measure and control vehicular speeds is far better now than it was 50 years ago. We don't need a 10% +2 fudge factor. That's just what we're accustomed to. And where I live the reality is that the fudge factor is 10mph over. The one major exception is school zones. And ain't it amazing how well almost every driver manages to comply so well with that?
You can easily demonstrate how well we can and do control vehicle speeds to what we want by observing how well the typical driver is at maintaining their speed just under the understood local "fudge factor. We are dnag near experts at it. We could be just as expert at keeping our speed just under the posted speed limit. It's a mindset and a choice, not a practical necessity.
You can easily demonstrate how well we can and do control vehicle speeds to what we want by observing how well the typical driver is at maintaining their speed just under the understood local "fudge factor. We are dnag near experts at it. We could be just as expert at keeping our speed just under the posted speed limit. It's a mindset and a choice, not a practical necessity.
I agree 10 mph over a low speed limit of say 30 would be nonsense, which is why percentage tolerances generally work better.
#131
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The studies I've seen suggest that traffic violations are about equal between cars and bicycles.
My observation is that cars and bicycles will both routinely roll stops when
1) it is obvious and clear that there is no cross traffic
2) they are not intersecting a faster and more major thoroughfare.
Someday I'll put a video camera up at a typical local stop and gather some stats on it. My bet is that 2/3rds of the drivers will roll the stop when they are alone.
I think it is actually safer and more expeditions for cyclists to treat stop signs as yield signs. That helps them clear the intersection quickly and is still quite safe. Some cities (apparently yours) have realized this and have changed regulations accordingly.
My observation is that cars and bicycles will both routinely roll stops when
1) it is obvious and clear that there is no cross traffic
2) they are not intersecting a faster and more major thoroughfare.
Someday I'll put a video camera up at a typical local stop and gather some stats on it. My bet is that 2/3rds of the drivers will roll the stop when they are alone.
I think it is actually safer and more expeditions for cyclists to treat stop signs as yield signs. That helps them clear the intersection quickly and is still quite safe. Some cities (apparently yours) have realized this and have changed regulations accordingly.
I bet some motorists think similarly, and hence the problems!
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#132
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Well that’s the thing. If the speed limit was enforced to say 1 mph then driving at an indicated speed limit might get you a ticket due to the slightest of measurement error. As I said, we can argue about tolerances and I just stated what our police forces use. It is not a social convention, it is what guarantees them a conviction without having to argue about instrument calibrations etc in court.
I agree 10 mph over a low speed limit of say 30 would be nonsense, which is why percentage tolerances generally work better.
I agree 10 mph over a low speed limit of say 30 would be nonsense, which is why percentage tolerances generally work better.
Apparently, their rules were strictly enforced only on the out of state cars.
Difference of approximately 5MPH at highway speeds tends to be difficult to conclusively prove as intentional because of some errors in speedometers (tire pressure, wear etc), it makes sense to have some latitude.
#133
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When I was visiting my in-laws years ago, they specifically warned me about a small town in a valley about their speed limit policies. They actually gave out tickets for going 1 mile over the speed limit. To challenge that citation, one has to go back to their court and no one wants to travel back to that town to deal with it and people simply paid the fine. A news reporter from a large city met the same fate while driving through this town. He wrote a small article in his paper, calling their police and traffic court Gestapo.
Apparently, their rules were strictly enforced only on the out of state cars.
Difference of approximately 5MPH at highway speeds tends to be difficult to conclusively prove as intentional because of some errors in speedometers (tire pressure, wear etc), it makes sense to have some latitude.
Apparently, their rules were strictly enforced only on the out of state cars.
Difference of approximately 5MPH at highway speeds tends to be difficult to conclusively prove as intentional because of some errors in speedometers (tire pressure, wear etc), it makes sense to have some latitude.
Speed limits are arbitrary round numbers anyway and almost exclusively in 10 mph increments. So I don’t see why they need to be enforced to the nearest 1 mph.
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#135
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Well that’s the thing. If the speed limit was enforced to say 1 mph then driving at an indicated speed limit might get you a ticket due to the slightest of measurement error. As I said, we can argue about tolerances and I just stated what our police forces use. It is not a social convention, it is what guarantees them a conviction without having to argue about instrument calibrations etc in court.
I agree 10 mph over a low speed limit of say 30 would be nonsense, which is why percentage tolerances generally work better.
I agree 10 mph over a low speed limit of say 30 would be nonsense, which is why percentage tolerances generally work better.
If the speed limit was enforced to 1mph, people would simply drive 2 or 3 mph under just as they do with the "understood" but not codified fudge factor. They regularly demonstrate the ability to control speed this closely.
Maybe "societal convention" would be a better term? All it would take is some simple law changes that reflect current technology and the argument about instrument calibrations narrows to a MPH or so.
#136
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Just about ever driver has access to a GPS and can easily check their speedometer accuracy. Most of us have. That's why most of us know within a mph or two how much we can exceed the posted speed limit.
#137
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I agree and they want motorists to support any speed limit enforcement in operation, which they are unlikely to do if they get a ticket for allegedly being 1 mph over the posted limit. The 10% +2 tolerance we have across the UK is generally seen as a fair cop if you get caught. It’s hard to argue that it isn’t a fair margin. It also means that you can actually drive at the posted speed limit without fear of receiving a ticket.
Speed limits are arbitrary round numbers anyway and almost exclusively in 10 mph increments. So I don’t see why they need to be enforced to the nearest 1 mph.
Speed limits are arbitrary round numbers anyway and almost exclusively in 10 mph increments. So I don’t see why they need to be enforced to the nearest 1 mph.
If everybody understood that the speed limit was an actual limit and that said limit was actually enforced, then it would seem perfectly fair to them if they got cited for 46 in a 45 mph zone. But the understanding is different. So of course they get upset if they aren't allowed the understood fudge factor.
This whole fudge factor scheme is a holdover from when speeding was generally determined by relatively crude schemes and cars had similarly crude speedometers. Today we have GPS, radar and lasers. I have a GPS on my wrist for goodness sake. It tracks my bicycle speed to fractions of a mph. It's inexpensive technology.
If we need this fudge factor for any reason, I can only imagine that it's psychological. Maybe we need to feel like we can break the law ... just a little bit. But this so much seems to me like setting your clock ahead in order to get to work on time.
#138
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Yet you offer as "better" a scheme that gives us a numbers like 46 mph, 57 mph and 68 mph (that we have to calculate in our heads) as actual effective limits.
If everybody understood that the speed limit was an actual limit and that said limit was actually enforced, then it would seem perfectly fair to them if they got cited for 46 in a 45 mph zone. But the understanding is different. So of course they get upset if they aren't allowed the understood fudge factor.
This whole fudge factor scheme is a holdover from when speeding was generally determined by relatively crude schemes and cars had similarly crude speedometers. Today we have GPS, radar and lasers. I have a GPS on my wrist for goodness sake. It tracks my bicycle speed to fractions of a mph. It's inexpensive technology.
If we need this fudge factor for any reason, I can only imagine that it's psychological. Maybe we need to feel like we can break the law ... just a little bit. But this so much seems to me like setting your clock ahead in order to get to work on time.
If everybody understood that the speed limit was an actual limit and that said limit was actually enforced, then it would seem perfectly fair to them if they got cited for 46 in a 45 mph zone. But the understanding is different. So of course they get upset if they aren't allowed the understood fudge factor.
This whole fudge factor scheme is a holdover from when speeding was generally determined by relatively crude schemes and cars had similarly crude speedometers. Today we have GPS, radar and lasers. I have a GPS on my wrist for goodness sake. It tracks my bicycle speed to fractions of a mph. It's inexpensive technology.
If we need this fudge factor for any reason, I can only imagine that it's psychological. Maybe we need to feel like we can break the law ... just a little bit. But this so much seems to me like setting your clock ahead in order to get to work on time.
GPS real time indicated speed is also far from accurate and lags way too much. That’s why pro cyclists (and vehicles) still use wheel speed sensors for more accurate real time speed display even though they have GPS.
Your idea of zero speed tolerance doesn’t allow anyone to drive at the actual speed limit without risk of a ticket. So the real limit is not really what is written on the sign any more.
#139
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Given that this fudge factor method of enforcement has been operational for generations it would take tremendous force and engender great public resentment to alter it. Would it be worth the Herculean effort?
#140
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And it would all be simpler if speed limits were imposed and effectively enforced onto the car. No calculating. Just put your foot to the floor, and the car would only drive as fast as it's allowed.
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Apparently that's already the situation with the big rigs. I'm sure you've been behind one big rig overtaking another at speed right? There's a woman sitting in jail right now because she forced an unsafe pass, killing another driver going "the limit". It was deemed 'road rage'. We already have a big problem with road rage. I don't drive. I absolutely have no dog in this hunt. Y'all's go ahead and make the roads 'safer' with millions (yes, millions) of frustrated drivers limited to some arbitrary limit. Whee doggie, when the fur starts flying, it will truly be something to see.
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I don't drive. I absolutely have no dog in this hunt. Y'all's go ahead and make the roads 'safer' with millions (yes, millions) of frustrated drivers limited to some arbitrary limit.
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I think I made the point upthread but it clearly bears repeating. What y'all's are really arguing for is automated vehicles. Be careful what you wish for. You WANT systems that will tell other drivers how fast to go but that is so 1990's. The 21st Century way is to just let the car do it. Another poster said he'd rather take the train. I had to scratch my head. Train? What train? Did he mean like ... Amtrak? ROFL.
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Not really. First, intent isn't even relevant. Second, if you think you can only be accurate to within 5mph, then the safe bet would be to drive 5mph below the speed limit. Problem solved.
Just about ever driver has access to a GPS and can easily check their speedometer accuracy. Most of us have. That's why most of us know within a mph or two how much we can exceed the posted speed limit.
Just about ever driver has access to a GPS and can easily check their speedometer accuracy. Most of us have. That's why most of us know within a mph or two how much we can exceed the posted speed limit.
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You clearly have no sense of irony. You throw sarcasm at me but you don't equate your "everybody should feel the way I do about cars" with a sense of 'holier than thou"? You may not have a 'need for speed' but you MUST know that not all of your fellow mouth-breathers are so evolved, right? Well, even if you don't know, the trained professionals whose job it is to know, already do. So it will never happen. Speed governing of cars will only happen once they are fully autonomous.
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There are various issues with this approach. As I mentioned earlier, we already have exactly this system in HGVs and it causes traffic congestion and safety issues with overtaking. It is only practical at all with HGVs because they are not allowed to drive in the outer lane of a motorway.
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It’s a total non-starter for practical, social, legal and political reasons. But other than that I don’t see any issue with that concept 😂
#148
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It seems that you and some of your A&S colleagues are advocating that all travelers on the roads be restricted to driving, or being driven, at a speed not to exceed what will make any theoretical nearby bicyclist ride "at peace."
#149
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My main wish is that cars would operate at slower speeds because they are much less likely to cause harm when they do. KE=1/2 mv² and all that.
And I've been part of dragging this off-topic bit on for too long, so that's the last I'll say on it.
Last edited by Jay Turberville; 12-22-23 at 11:30 AM.
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There are various issues with this approach. As I mentioned earlier, we already have exactly this system in HGVs and it causes traffic congestion and safety issues with overtaking. It is only practical at all with HGVs because they are not allowed to drive in the outer lane of a motorway.