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Can a single car break a traffic jam?

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Re: Can a single car break a traffic jam?

#81

Post by dsl »

GigabyteCoin wrote: post #23
logn wrote: post #15

I often try the technique of leaving lots of space and going at a slower, steady pace. One problem is that everyone re-routes around you, and you induce road rage and traffic weaving. The other problem is that unless it's a straight stretch of road, you have no idea what speed is slow enough.

Truckers (professional drivers) do this all the time. If ever there is a traffic jam on the highway, you will see the big rigs consistently leaving hundreds of feet of space in front of them. They also seem to concentrate in the center lanes of the highway for reasons I haven't figured out yet.

Semi trucks aren't trying to calm traffic, they are maintaining a consistent speed (or rather engine RPM) and gear for fuel efficiency. Drivers are paid per mile and the further they can go on a single fill-up is more money in their pocket.

Edit to add: It is a computer telling them how fast to go, usually something similar to http://www.scangauge.com/

Re: Can a single car break a traffic jam?

#84

Post by bpchaps »

seanp2k2 wrote: post #65
arprocter wrote: post #51

Earlier quoted context omitted.

A game I used to play with myself on the highway was to simply try and use my brakes as little as possible - when you see brake lights ahead it's instinctual to also brake yourself, but often if you have a long enough follow distance you can just lift off the gas. Brake lights being a binary representation of an analogue pedal is another problem, although iirc on some newer cars the lights are brighter/more lights go…

IMO if you have to brake on the freeway, someone made an error. Cool about brake lights; I've wondered for years why they don't do this. I knew about some newer cars flashing the hazard lights in a very hard stop, but didn't know any were doing brake light meters. Any idea which specific models? I'd love if they standardized the messaging across brands and countries; imagine a new mustang where 1 vertical bar on each…

I used to ride a motorcycle every day from the suburbs to Chicago's loop (until a crash on the way to work. heh) and I'm not sure that I'd want something like this. As binary as it initially seems, there's actually a lot more contextual information to it than you'd think. The swerviness, the length of the brake, how straight their car's going, how often they do it, head position, how in depth their conversations seem to be, etc. Like a lot of riders out there, I started playing mini games to try and figure out what the drivers were doing to help with determining risk. For me, imagining the physical position of their driving limbs, as weird as that may sound, was the most help. Thinking the problem in those terms helped out and really pushed the idea that if their foot is hovering over the brake, then a lot of caution is needed. I don't do this as much in a car, and I doubt many drivers do this, or anything close to it.

I think that if something like this was implemented, then a lot of people would use it as a crutch and make poor decisions based on implied safety eg, "His light didn't blink three times, so I didn't think to stop." That, and a lot of new cars, for some stupid reason, seem to want to obfuscate the significance of brake lights by just having them be brighter versions of on-by-default lights anyway or similar.

There definitely is something along those lines that'd be helpful, but I think it might have to be all or nothing there. Flooding phone frequencies with white noise might work, though ;)

Re: Can a single car break a traffic jam?

#87

Post by yoha »

dsfyu404ed wrote: post #79
cpeterso wrote: post #55

Earlier quoted context omitted.

In a traffic jam, wouldn't the alternative to leaving plenty of space be constantly starting and stopping? That seems pretty like a lot of work for the driver in a big rig.

ding ding ding ding! We have a winner. The just leave it in the fastest gear that is slow enough to not hit the car in front of them. For the extra 5min it costs it's a lot easier than pushing a bazillion pound clutch twice per cycle.

Offtopic:

> ding ding ding ding! We have a winner.

I cannot speak for others, but, at least to me, this reads as extremely condescending: it makes it sound like other commenters are basically picking arguments at random and you are the only one to know the truth.

Re: Can a single car break a traffic jam?

#88

Post by therein »

alphapapa wrote: post #62
bagacrap wrote: post #30

Earlier quoted context omitted.

The other problem is that this isn't scalable. Imagine a traffic jam that stretches for miles. Now imagine that same jam where everyone has left an extra three car lengths in front of them. You're suddenly using a lot more road per car. Tailgating actually seems like the most efficient use of space to me, provided you tailgate effectively (don't yo-yo).

Not only is tailgating unsafe, but it's not possible to do it effectively. Even if you are a super-skilled racing driver, the driver ahead of you isn't, and he will slam on his brakes at the last second, forcing you to do the same, forcing the car behind you to do the same...rinse and repeat. Or you will hit him, or the car behind will hit you, etc, causing another accident and another traffic jam. That's how the tra…

...or, according to what you say, being one of those idiots that are going to get made and zoom around once in a while.

Either way, this makes me think that a model where cars that are okay with driving slowly spreading around but leaving plenty of space in front of them. Similar to how (in California at least) motorcycles can filter filter though the traffic, cars that are impatient can use the large spacing between the slow moving cars to move forward.

Re: Can a single car break a traffic jam?

#89

Post by bsder »

ThrustVectoring wrote: post #73
PantaloonFlames wrote: post #72

Earlier quoted context omitted.

> Aim for a hard speed limit (maybe the actual speed limit). That's not gonna work. Depends on the day, the time, the weather, rain, fog etc. Some days, traffic flows at 70 on 405 during rush hour. If you go the legal speed limit you will be the dangerous blockage that makes everyone else down, and makes a few people unnecessarily grumpy. Other days it's misty because the water on the road gets stirred up by all the…

Enforcing a speed limit on freeways is completely possible. They've got it done in England. What you need to do is capture license plates on entrance and exit, and calculate the average speed for each car's trip. If the speed limit is 50 MPH for traffic-flow reasons, and you do your 15 mile commute in 15 minutes, you're getting a "60 in a 50 MPH zone" ticket in the mail, every single time. People will learn in a hurr…

This works in the UK because

1) a lot of non-artery roads are really shitty in the UK 2) the UK is an island with lots of rivers and lakes so you may not have an option besides that particular road 3) UK average trips are likely much shorter

If they enforced speed limits on roads in the US with that technique, that road would simply stop being used. There are almost always other options, and the further you are traveling, the more options there are.

Re: Can a single car break a traffic jam?

#90

Post by feelix »

I've always wanted to see what would happen if the government employed workers (maybe traffic cops) to take up each lane on the motorway, and form a line that you can't get passed, and drive at a speed just right to unclog traffic jams during peak hours.

I wonder how much more throughput and time saved we could get just by having lines of breakers every 50km or so on a highway during peak times.

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