• HaraldvonBlauzahn@feddit.orgOP
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    3 days ago

    Why would people want to make it less efficient.

    Slower speeds are more efficient.

    This is because at higher speeds, far more safety distance is needed. Because it is dominated by the braking distance, the safety distance increases roughly quadratic with speed. The transport capacity of a steet is however defined by speed divided by safety distance times its lanes. Which means that at higher speed, fewer vehicles per second can pass a point. And small, slow city streets can easily, and safely, transport more vehicles per second than a highway.

    That’s also why at an airport, a plane needs a runway with kilometers of free space for a single plane. It is the speed, which requires lots and lots of longitudinal space to retain safe control.

    This is also why high-speed highway interchanges are often larger than entire mid-sized European inner cities like, for example, Aachen. You can see this well on satellite pictures on Google maps. Car infrastructure wastes enormous amounts of space.

    And this is also why bike paths can generally transport far more vehicles per second than streets for cars. For example, Copenhagen has a bicycle bridge that spans the harbour, which is called Cykelslangen. It has only two lanes, and at rush hour times, it transports over two vehicles per second - 7200 vehicles per hour.

    • ladicius@lemmy.world
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      3 days ago

      Yep. Exactly this. Concept of “green wave” (“Grüne Welle”), traffic lights coordinated to keep vehicles flowing at a steady pace, has been used and been proven effective in Germany since the 1980s. Reduces all kinds of emissions and also reduces crashes. Improves traffic flow a lot.

  • Azrael@feddit.org
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    3 days ago

    So… they finally started using Induction Loops in the US?

    Those have been around in Germany for decades. Especially in town and in “traffic calmed” zones. Your Vehicle passes over the induction loop, the traffic light switches to red and has a calculated timer that goes like “distance from loop to intersection, travelled at correct speed equals 17 seconds” so when you drive faster than the correct speed, the lights will not have reached the end of the timer and will not have switched. Combine that with a red light camera and geez look at that, people know how to drive slowly in Areas with playing children!

    • infinitesunrise@slrpnk.net
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      2 days ago

      We’ve had induction loops in most signaled intersections here for decades, it’s just that we tend to only use them for measuring how many vehicles are waiting at a red. Some lights won’t even go green unless they detect a vehicle stopped over the loops.

    • cravl@slrpnk.net
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      2 days ago

      Making the sensing (whether loop- or camera-based) speed-aware seems to be the headline here. Which, does exist here plenty already, but I would love to see it even more often. Signage expaining that the lights are timed to X MPH would be helpful too, for the people that wouldn’t pick up on that naturally (quite possibly the majority here, sadly).

  • radish6367@lemmy.ca
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    3 days ago

    I can’t wait for the carbrain victim complex to conjure up complaints of being punished for speeding. In Ontario, there were drivers (publicly, in news articles) saying that they’re essentially too distracted while driving to keep track of the speed limit and their speed relative to it. This was their argument against speed cameras. Incredible.