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Device Stops Speeders From Inside Car

frdmfghtr writes "CNN reports that the Canadian government is testing a new anti-speeding device." From the article: "The system being tested by Transport Canada, the Canadian equivalent of the U.S. Department of Transportation, uses a global positioning satellite device installed in the car to monitor the car's speed and position. If the car begins to significantly exceed the speed limit for the road on which it's traveling the system responds by making it harder to depress the gas pedal, according to a story posted on the Toronto Globe and Mail's Website."

5 of 781 comments (clear)

  1. Re:Full Monty by Phanatic1a · · Score: 5, Informative
    Although there's an idea... If you speed, you don't get any music or radio. Because, obviously, you need all your attention on the road right then.

    What a bunch of fucking nonsense.

    Look, traffic engineers know, and have known for a very long time, that the safest speed to set speed limits at is the 85% percentile speed: the speed which 85% of the free-flowing traffic on that particular road travels at or below. This is because the large majority of drivers are reasonable and prudent, and while they wish to reach their destination in a short amount of time, they also wish to remain alive and unwrecked.

    If traffic engineers want this speed on a stretch of hypothetical road to drop, they do this by changing the road surface. Narrows, curves, crests, inclines, will all reduce the 85th percentile speed.

    Setting a speed limit lower than the 85th percentile speed doesn't reduce the speed at which traffic flows. I'm going to repeat that again, because it sounds vaguely important:

    Changing the speed limit doesn't change how fast people drive. The safe speed for a road is determined by the road design and the road conditions, and *not* by some arbitrary number on a sign.

    The notion that traveling at the posted limit +5 is more dangerous than traveling at the posted limit, or than traveling at the posted limit -5, is reasonable only if the posted limit reflects the 85% percentile speed.

    Sometimes it does. Some states even have it written into their laws that that's how speed limits are determined.

    But more often it does not. More often, speed limits are set artificially low, in order to provide a source of revenue for the state. If you set a speed limit below the 85% percentile speed, people will generally ignore it, drive at the speed dictated by road conditions and their ability, and then you can ticket them for speeding.

    Here are the actual conclusions of that study I linked to just above:

    Based on the free-flow speed data collected for a 24-h period at the experimental and comparison sites in 22 States, posted speed limits were set, on the average, at the 45th percentile speed or below the average speed of traffic

    At sites where speed limits were raised, there was an increase of less than 1.5 mi/h (2.4 km/h) for drivers traveling at and below the 75th percentile speed. When the posted limits were raised by 10 and 15 mi/h (16 and 24 km/h), there was a small decrease in the 99th percentile speed.

    Raising speed limits in the region of the 85th percentile speed has an extremely beneficial effect on drivers complying with the posted speed limits.

    Lowering speed limits in the 33rd percentile speed (the average percentile that speed were posted in this study) provides a noncompliance rate of approximately 67 percent.

      Accidents at the 58 experimental sites where speed limits were lowered increased by 5.4 percent. The level of confidence of this estimate is 44 percent. The 95 percent confidence limits for this estimate ranges from a reduction in accidents of 11 percent to an increase of 26 percent.

      Accidents at the 41 experimental sites where speed limits were raised decreased by 6.7 percent. The level of confidence of this estimate in 59 percent. The 95 percent confidence limits for this estimate ranges from a reduction in accidents of 21 percent to an increase of 10 percent.

      Lowering speed limits more than 5 mi/h (8 km/h) below the 85th percentile speed of traffic did not reduce accidents.


  2. Just to get the facts straight: by DancesWithBlowTorch · · Score: 5, Informative

    Sorry, but you got a few things wrong. Although you might be essentially right, let me be a Fact-Nazi (got it? A German, calling himself a Nazi. Funny, huh? Aw...):

    1. The mandatory check-up (so-called "Hauptuntersuchung") is every _other_ year, and only after four years for a new car. Still, judging from what I see on `Pimp my ride', it is possible in the states to drive cars that would never be allowed on public streets in Germany.

    2. Nobody is "happily driving at 250+ Km/h". Yes, I have been overtaken by the occasional Porsche doing 300 km/h (~190 mph) and Mercs at 220 km/h are not exactly a rare sight, but these people are notorious for closing up to an arm's reach of your bumper with headlights flashing; and they are generally considered arseholes with tiny wangs.

    3. About 60% of the Autobahn network (that's an estimate, I couldn't be bothered to look it up) have speed limitation, typically 120 km/h. That doesn't stop people from speeding there, but they get caught sooner or later (the Autobahn police squad sports disguised, camera-fitted cars with appropriate engines)

    4. From what I hear from friends with American licenses, you are right about driving licences.

    5. Accidents don't happen on Autobahns. They happen on county roads with sharp curves, crossroads and narrow passages. Due to the Autobahn's construction (or any other Highway's, for that matter), head-on crashes are nearly impossible, and deadly crashes are much rarer than they are on county roads (believe me, I am an EMT...)

  3. Re:Full Monty by mesocyclone · · Score: 5, Informative

    The poster seems to be under the delusion that speed limits are always tied to the current maximum safe speed.

    This is absurd, as other factors can be at work:

    political (the town I live in has 5mph lower speed limits on exactly the same roads and road conditions as the towns around it - and not coincidentally is the first town in the US to use photo-radar).

    legal - in the US, every state (except perhaps one) has an absolute maximum for speed limits. Clearly some roads and vehicles are capable of being driven safely at much higher speeds on some road segments in those states. Not that long ago, the idiot Jimmy Carter forced a 55mph maximum speed limit throughout the US, that lasted until 1994. The interstate highway system was built for much higher speeds (I believe 75mph) and the Kansas Turnpike for 80mph, it's previous speed limit.

    safety for non-familiar drivers - a road can have conditions which make the maximum safe speed lower than the apparent (to non-familiar drivers) safe speed. The authorities may choose to set the speed limit lower to compensate.

    weather - the speed limit may be lowered to compensate for common but not continuous weather conditions such as high winds.

    Traffic engineers used to set speed limits, in the absence of other factors, determining the 85th percentile speed of unconstrained drivers. In other words, presumably 85 percent of the drivers, based on their experience and perceptions, drove at or below the maximum safe speed. They would, of course, set them lower at hard to see hazards such as hidden curves.

    If one is going to have such a system, soft but effective feedback seems much better than hard limits.

    BTW... some cars have unadvertised built-in speed limits. My 2001 Toyota Sequoia appears to have a 100mph limit. One day on a storm chase, on a very good road with almost infinite visibility, we tried it, and at 100mph the engine refused to go faster, even though it clearly had the capacity. I suspect this may be because they didn't want to put bigger tables into the engine computer.

    --

    The only good weather is bad weather.

  4. Re:Full Monty by raoul666 · · Score: 4, Informative

    In regards to your ambulance point: actually, on the way to accident scenes, those things do go well over the speed limit. So do police cars and fire trucks. Once the person is in the ambulance, yes, they slow down - the person is already getting medical attention. But shaving 30 seconds off a 5 minute trip to get to the guy having a heart attack can easily be the difference between life and death.

    Also, there are times (rare, yes) when speeding to the hospital is not the worst idea. The hospital where I live is slightly out of town, and to get there you have to go on a highway of sorts. The limit is 60km/h for part of it. Oh a straight road, no lights, no fast turns or merging traffic, if it was 4 in the morning and someone was dying in my backseat, going up to 100 would not be an issue.

    --
    When cryptography is outlawed, bayl bhgynjf jvyy unir cevinpl
  5. Re:Full Monty by niko9 · · Score: 4, Informative

    As a New York City Paramedic, I agree. Here in New York State, we are never alowed to exceed the speed limit, no matter what the scenario. We are (same goes for FDNY) not even allowed to take red lights. Only the NYPD can do that.

    The sick person being transported to the hospital is already sick, there is no exuse to jeopardize the public after the fact. The same holds true for responding to calls.

    There have been quite a few case lately were EMTs or Paramedics have received jail time for their reckeless driving.