Whoops... :(

[hounddog]

The night vision thing I think you're dead on about, but i still think 2.5 seconds is way high. Everyday on my way to work goes down 275, and traffic is not only usuall very heavy, but often still moving at 75 MPH+. Cars aren't more than 40 feet apart at the most. If it was taking even 10% of these people 2.5 seconds to react to the brake lights in front of them, my ride to work would invlove danger verging on suicidal.

Its nowhere near that bad.


At least not most days.

No offense, but I would have a hard time believing that 275 ever moves at 75 during morning commute.? Especially as you draw nearer to the city.? Now, if you are traveling away from the city toward the suburbs I can believe it.? ?Although, I give you that 275 is pretty far out from Detroit.  Try that on I-696 E/B sometime!   :P   But if that reaction time is far too high, why are rear end collisions the most common crash in Michigan?? Speed?? Following too closely?? Long reaction times?? Combinations of all above?? Others?

[Raghavan]

2.5 seconds to react to brake lights is a lot!

[hounddog]

2.5 seconds to react to brake lights is a lot!

Exactly.  That is why the most common traffic crash in Michigan is the Fail to Stop In Assured Clear Distance Ahead.  (rear ender)

[Raghavan]

Exactly.  That is why the most common traffic crash in Michigan is the Fail to Stop In Assured Clear Distance Ahead.  (rear ender)

So you're saying that most people have horrible reaction times?

[hounddog]

So you're saying that most people have horrible reaction times?

No, the Unversity of Michigan, Traffic Safety Program is.  I am only agreeing with them because they have people far smarterer then me working for them.

[hounddog]

but i still think 2.5 seconds is way high.

Try this then;
Count "one, one thousand, two one thousand." 

You just basically counted 2.5ish seconds and at 75mph you traveled about ________   feet. 

[TurboDan]

2.5 seconds to react to brake lights is a lot!

That's the beauty of LED brake lights.  I know, personally, it lowers my reaction time significantly.

The worst are the older American cars that have the brake light and turn signal light using the same bulb.  You never know if they're braking or turning, and since everything is flashing at once, which way they are turning.

[omicron]

That's the beauty of LED brake lights. I know, personally, it lowers my reaction time significantly.

The worst are the older American cars that have the brake light and turn signal light using the same bulb. You never know if they're braking or turning, and since everything is flashing at once, which way they are turning.

However, they are awesomely cool, which outweighs any safety concerns that may exist.

[Soup DeVille]

No offense, but I would have a hard time believing that 275 ever moves at 75 during morning commute.? Especially as you draw nearer to the city.? Now, if you are traveling away from the city toward the suburbs I can believe it.? ?Although, I give you that 275 is pretty far out from Detroit.? Try that on I-696 E/B sometime!? ?:P? ?But if that reaction time is far too high, why are rear end collisions the most common crash in Michigan?? Speed?? Following too closely?? Long reaction times?? Combinations of all above?? Others?

Well, I don't go to work in the morning, but yes it does. I drive from Rochester Hills to Westland, so right through the heart of I-696 as well.

Yes, rear end collisions are common, but nowhere near as commn as your numbers would seem to suggest. On either of these roads we're talking about they carry over 100,000 cars per hour and sometimes way more than that. Yet there aren't more than half a dozen fender benders on the worst day.

[Soup DeVille]

Try this then;
Count "one, one thousand, two one thousand."?

You just basically counted 2.5ish seconds and at 75mph you traveled about ________? ?feet.?

275 ft.

Now, if I leave more than about forty feet between me and the car in front of me, somebody will see that as an open spot and pull into it.

Alll I'm saying is that when you start adding up all the times and distances something doesn't, well, add up.

[Soup DeVille]

That's the beauty of LED brake lights.? I know, personally, it lowers my reaction time significantly.

The worst are the older American cars that have the brake light and turn signal light using the same bulb.? You never know if they're braking or turning, and since everything is flashing at once, which way they are turning.

Old school "standard" 12V incandescent lights can take between 200 and 250 ms to reach 90% luminosity. Modern brake light bulbs are what are considered "fast" incandescent, and take about 75 to 115 ms to light the same amount. LEDs take about 50 ms: making the difference between the worst and the best about 2/10ths of a second.

Which would be a significant percentage of your "standard" reaction time was about .75 seconds, but not very consequential if it was in the 2.5 second range.

[James Young]

hounddog responds to Raghaven:

No, the Unversity of Michigan, Traffic Safety Program is [saying that most people have horrible reaction times] ?

The University of Michigan has a Transportation Research Institute, of which Traffic Safety Program is a minor part denominated as ?Community-based Traffic Safety,? and which conducts no research.? Assuming that you are referring to one of these studies from UMTRI, I?d like to know which one so that I can get it through inter-library loan system.

?Reaction Times to Body-Color Brake Lamps,? D. Chandra, 1994
?Reaction Times to Body-Color Brake Lamps,? D. Chandra, 1992
?Reaction Times to High-Contrast Brake Lamps,? M. Sivak, 1990
?Reaction Times to Neon, LED, and Fast Incandescent Brake Lamps,? M. Sivak, 1993
?Reaction Times to Neon, LED, and Fast Incandescent Brake Lamps,? M. Sivak, 1994

If it is another study to which you refer, please indicate and I?ll go after it.?


According to NHTSA research conducted at the University of Iowa, on both a driving simulator and a test track, we obtained the following summarized data:

   ? ? ? ? ? ? ? ? ?IDS   ? ? ? ? ? ?? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?? ? ? ? ?Test Track
Initial Accel   0.96 second? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?    1.28 second
Release   ? ? ? ? ? ? ? ? ?0.21 SD   ? ? ? ? ? ? ? ?? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? 0.29 SD
      
Total Brake RT   2.2 second   ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? 2.3 second
(to max brake)   0.44 SD   ? ? ? ? ? ?? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?0.46 SD
      
Time to initial
steering   ? ? ? ? ? ? ? ? 1.64 second   ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?1.67 second

Note and explanation:? ?IDS? is the Iowa Driving Simulator, the test track is at Iowa City.? ?Initial Accel Release? is the total elapsed time from the incursion requiring a reaction to the release of the accelerator pedal.? ?Total Brake RT to max. brake? is the total time from incursion to maximum braking efficiency (both ABS and conventional).? ?Time to initial steering,? itself a legitimate evasive action, in addition to the braking is the total elapsed time from incursion to first movement (defined as x degrees of rotation?? Not given) of wheel.? Note that these actions occur simultaneously.?

Note also that these definitions are more stringent than time from recognition to time of first braking.

?DRIVER REACTION TIME IN CRASH AVOIDANCE RESEARCH:? VALIDATION OF A DRIVING SIMULATOR STUDY ON A TEST TRACK? by Daniel V. McGehee Elizabeth N. Mazzae? and G.H. Scott Baldwin, ?University of Iowa NHTSA VRTC TRC, Inc.

See also, Broen, N. and Chaing, D. (1996). ?Braking response time for 100 drivers in the avoidance of an unexpected obstacle as measured in a driving simulator.? Proceedings of the Human Factors and Ergonomics Society 40th Annual Meeting. pp. 900-904.

[hounddog]

Well, I don't go to work in the morning, but yes it does. I drive from Rochester Hills to Westland, so right through the heart of I-696 as well.

Yes, rear end collisions are common, but nowhere near as commn as your numbers would seem to suggest. On either of these roads we're talking about they carry over 100,000 cars per hour and sometimes way more than that. Yet there aren't more than half a dozen fender benders on the worst day.

My numbers?  I do not think I gave numbers for "REC" crashes. 

[Soup DeVille]

My numbers?? I do not think I gave numbers for "REC" crashes.?

Your reaction time numbers.

[hounddog]

Now, if I leave more than about forty feet between me and the car in front of me, somebody will see that as an open spot and pull into it.

I hate that!  Those people need to be run over.  Thrice.  Once when I run over them going forward, once when I back up to see if I knew them, and once when I drive away.

[TurboDan]

Old school "standard" 12V incandescent lights can take between 200 and 250 ms to reach 90% luminosity. Modern brake light bulbs are what are considered "fast" incandescent, and take about 75 to 115 ms to light the same amount. LEDs take about 50 ms: making the difference between the worst and the best about 2/10ths of a second.

Which would be a significant percentage of your "standard" reaction time was about .75 seconds, but not very consequential if it was in the 2.5 second range.

All I'm saying is that I can tell that my response to the LEDs is faster.

Additionally, it wasn't the response to the old American car lights that bothered me - it was that the brake lights and turn signals used the same bulb.  It was sometimes hard to tell if a car was braking or turning, or which way it was turning, since all of the lights would be going on an off as someone was slowing down.

[dazzleman]

All I'm saying is that I can tell that my response to the LEDs is faster.

Additionally, it wasn't the response to the old American car lights that bothered me - it was that the brake lights and turn signals used the same bulb.? It was sometimes hard to tell if a car was braking or turning, or which way it was turning, since all of the lights would be going on an off as someone was slowing down.

I don't see what the big issue is, Dan.  People who drive those types of cars never use directional signals anyway....

[Soup DeVille]

I don't see what the big issue is, Dan.? People who drive those types of cars never use directional signals anyway....

Heck, I used to use hand signals...

[Raza]

People who don't use signals are in my very special, very exclusive "I'm Going to Shoot You in the Face" Club.  The best thing is that you earn benefits quite quickly.

[TBR]

I think Dan is saying that the brightness of LED lights catch his attention faster.

[ifcar]

All I'm saying is that I can tell that my response to the LEDs is faster.

Additionally, it wasn't the response to the old American car lights that bothered me - it was that the brake lights and turn signals used the same bulb.  It was sometimes hard to tell if a car was braking or turning, or which way it was turning, since all of the lights would be going on an off as someone was slowing down.

Worse is the design in which taillights just get brighter in braking, often accentuated by the third brakelight being burned out.

[Champ]

I never understood why there isn't some kind of regulation on lights @ the rear of the car.

Separate turn signals, separate lights that come on when you brake, and a regular set of taillights that are always on when the headlights are on.  Also all cars should have side markers, separate from the headlamp/parkinglight assembly up front.  (Usually behind the front wheel well on most cars that do have them)

[omicron]

I never understood why there isn't some kind of regulation on lights @ the rear of the car.

Separate turn signals, separate lights that come on when you brake, and a regular set of taillights that are always on when the headlights are on. Also all cars should have side markers, separate from the headlamp/parkinglight assembly up front. (Usually behind the front wheel well on most cars that do have them)

Never! '65 Thunderbird sequentials all the way!

[the nameless one]

I have presented the evidence that multiple places use traffic citations as major revenue sources.?

You've presented that a few places do that; just a few places. Even if it WAS a LOT of places, the overriding issue was whether the violation was commited or not,. not the revenue that resulted . No fine imposed is no incentive to obey the traffic laws, as I've stated before. They could  be making millions of dollars and thats not in and of itself a bad thing, as long as the violation was actually commited and the fine imposed as a result. Maybe a whole bunch of people need to be better drivers, and they wouldn't be paying fines.

[James Young]

the nameless one writes:

You've presented that a few places do that; just a few places. Even if it WAS a LOT of places, the overriding issue was whether the violation was commited or not,. not the revenue that resulted . No fine imposed is no incentive to obey the traffic laws, as I've stated before. They could  be making millions of dollars and thats not in and of itself a bad thing, as long as the violation was actually commited and the fine imposed as a result. Maybe a whole bunch of people need to be better drivers, and they wouldn't be paying fines.

Do you really get more obtuse with every post or is that just my imagination?

Oklahoma has nearly 200 speedtraps of varying degrees, including those that have been shut down by the state for abuse of their enforcement privileges [official state terminology].  Texas has nearly 500 speedtraps of varying degrees, not including Three famous ones that no longer feel the need for Draconian enforcement since they have developed vast retail resources  and no longer need to enforce for money.  Isn?t it funny how  Home Depot and Neiman-Marcus mitigate a speeding problem?  But I digress.

Sorry, the overriding issue is the intent of the decision by the jurisdiction ? not the officer ? how vigorously to pursue speeding as well as the degree to which the jurisdictional budget is driven by fines.  Any budget that is 80% speeding fines is a problem and degrades the legitimacy of the jurisdiction so structured.

Speeding ? exceeding an arbitrary number ? is ubiquitous.  To cite for it, absent an egregiously dangerous accompanying act, is criminal and degrades the jurisdiction demanding such cites as well as the cop who prostitutes himself to write them. 

Keep in mind that ?better drivers? are determined by the absence of crashes, injuries, and fatalities as well as that driver?s contribution to rapid and efficient traffic flow rather than avoiding tickets. 

Also keep in mind that redirecting all fines, fees and costs collected to a non-profit public corporation (i.e., away from the issuing jurisdiction) would retain the economic disincentive that you like so much but remove any incentive to cite, thus assuring that any cites would be for legitimate reasons. 

[GoCougs]

Also keep in mind that redirecting all fines, fees and costs collected to a non-profit public corporation (i.e., away from the issuing jurisdiction) would retain the economic disincentive that you like so much but remove any incentive to cite, thus assuring that any cites would be for legitimate reasons.?

That much I could go for.

[James Young]

That much I could go for.

Sweet Chocolate Jesus!  I think the Earth just wobbled in its orbit.   

[the nameless one]

the nameless one writes:

Do you really get more obtuse with every post or is that just my imagination?

Oklahoma has nearly 200 speedtraps of varying degrees, including those that have been shut down by the state for abuse of their enforcement privileges [official state terminology].? Texas has nearly 500 speedtraps of varying degrees, not including Three famous ones that no longer feel the need for Draconian enforcement since they have developed vast retail resources? and no longer need to enforce for money.? Isn?t it funny how? Home Depot and Neiman-Marcus mitigate a speeding problem?? But I digress.

Tinfoils on too tight James; you see a "speedtrap" behind every billboard and roadside tree.

Sorry, the overriding issue is the intent of the decision by the jurisdiction ? not the officer ? how vigorously to pursue speeding as well as the degree to which the jurisdictional budget is driven by fines.? Any budget that is 80% speeding fines is a problem and degrades the legitimacy of the jurisdiction so structured.

A jurisdictions intent to pursue speeding vigerously does not mean they have sucumbed to the Dark Side, James. Perhaps they truly view speed as a pressing problem. Maybe these are jurisdictions where they are doing a lot of interdiction stops where the speed isn't their primary concern but the pretext for the stop, but the agency has no written warning alternative to the speed cite so thats what gets issued. There are a multitude of reasons beyond what you offer that could reasonably explain things.

I don't automatically see a problem with a budget being 80 % fine based.  No tax base and a lot of tickets means the per centage will be skewed.

Once again, was the offense committed or not? Now, if you are going to suggest that the tickets and their cited violations were fabricated, thats an issue.

Speeding ? exceeding an arbitrary number ? is ubiquitous.? To cite for it, absent an egregiously dangerous accompanying act, is criminal and degrades the jurisdiction demanding such cites as well as the cop who prostitutes himself to write them.?

We know, we know...you worship at the alter of unrestricted speed.

No, it doesn't make the officer a criminal.

Keep in mind that ?better drivers? are determined by the absence of crashes, injuries, and fatalities as well as that driver?s contribution to rapid and efficient traffic flow rather than avoiding tickets.?

No, I can think of plenty of drivers who avoid crashes, injuries and fatalities buit are in fact horrendous drivers.

Also keep in mind that redirecting all fines, fees and costs collected to a non-profit public corporation (i.e., away from the issuing jurisdiction) would retain the economic disincentive that you like so much but remove any incentive to cite, thus assuring that any cites would be for legitimate reasons.?

And exactly WHAT non-profit gets designated to receive this cash flow? How do you handle the bitching from the other non-profits who would certainly clamour to get a slice of the pie?

[Tave]

I'll buy that, ON AVERAGE, stopping distances increase 4-fold in relation to speed. In emergency situations they do not, but in the course of normal driving, no one is stomping on their brakes at every opportunity. To maintain a pleasant ride, people brake long and soft comming off the interstate.

[Champ]

I'll buy that, ON AVERAGE, stopping distances increase 4-fold in relation to speed. In emergency situations they do not, but in the course of normal driving, no one is stomping on their brakes at every opportunity. To maintain a pleasant ride, people brake long and soft comming off the interstate.

But we are talking about emergency braking.