Can a single car break a traffic jam? • Hacker News Board

Re: Can a single car break a traffic jam?

#91

Post by stinos » Sat, Apr 30, 2016, 7:39 AM UTC

arprocter wrote: post #51

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.

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…

use my brakes as little as possible

I play this 'game' all the time, everywhere, and when it's time to slow down more than what simply releasing the pedal does I'll first try to shift down and have the engine brake for me. The latter not only because it lowers fuel usage but also because it makes me keep even more distance, which is the key point for me. It is just so much safer (hitting another car because you cannot brake in time isone of the most common accident types) and leads to much more relaxed driving without fast acceleration/deceleration. Only disadvantage so far: other drivers not understanding it and passing you in anger.

Re: Can a single car break a traffic jam?

#92

Post by danenania » Sat, Apr 30, 2016, 8:36 AM UTC

arprocter wrote: post #49

I wonder how much of this is mitigated by good lane discipline? My SO actually got pulled over the other day (or at least that's what the cop used as an excuse) for driving in a passing lane when not passing anything. I said I was glad because it's a terrible habit - every lane ending up going the same speed as the slowest driver

Lane discipline makes a huge difference. It's what makes driving 110mph on the Autobahn safer than driving 70 on a busy US highway.

Re: Can a single car break a traffic jam?

#93

Post by Houshalter » Sat, Apr 30, 2016, 8:39 AM UTC

A long long time ago, I stumbled onto the personal website of a guy who was really into this. He had little simulations of different types of traffic patterns, and how a single car could break it and return it to normal. It was really interesting, but I don't have the slightest idea on how to find that website again if it even still exists.

EDIT: Found in the comments, this may have been it. Honestly don't remember: http://trafficwaves.org/

Re: Can a single car break a traffic jam?

#94

Post by iwwr » Sat, Apr 30, 2016, 8:51 AM UTC

stinos wrote: post #91

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…

use my brakes as little as possible I play this 'game' all the time, everywhere, and when it's time to slow down more than what simply releasing the pedal does I'll first try to shift down and have the engine brake for me. The latter not only because it lowers fuel usage but also because it makes me keep even more distance, which is the key point for me. It is just so much safer (hitting another car because you canno…

Still, instead of wearing out the cheap & quick to replace break pads, you wear out your transmission.

Re: Can a single car break a traffic jam?

#95

Post by furyofantares » Sat, Apr 30, 2016, 8:56 AM UTC

Houshalter wrote: post #93

A long long time ago, I stumbled onto the personal website of a guy who was really into this. He had little simulations of different types of traffic patterns, and how a single car could break it and return it to normal. It was really interesting, but I don't have the slightest idea on how to find that website again if it even still exists. EDIT: Found in the comments, this may have been it. Honestly don't remember:…

This was one of the first sites I remember finding, in the late 90s. Back then it was hosted on the personal website provided by the author's dialup ISP, eskimo.com, as I recall.

Edit: I just noticed it still is hosted by eskimo.com, it just has its own domain now.

Re: Can a single car break a traffic jam?

#96

Post by xixixao » Sat, Apr 30, 2016, 10:13 AM UTC

iwwr wrote: post #94

stinos wrote: post #91

Earlier quoted context omitted.

use my brakes as little as possible I play this 'game' all the time, everywhere, and when it's time to slow down more than what simply releasing the pedal does I'll first try to shift down and have the engine brake for me. The latter not only because it lowers fuel usage but also because it makes me keep even more distance, which is the key point for me. It is just so much safer (hitting another car because you canno…

Still, instead of wearing out the cheap & quick to replace break pads, you wear out your transmission.

If you are shifting correctly that is not the case. The "breaking" is achieved by the engine, the wear on the transmission is the same as when you are stepping on the gas.

Re: Can a single car break a traffic jam?

#97

Post by iokanuon » Sat, Apr 30, 2016, 2:57 PM UTC

dsl wrote: post #81

GigabyteCoin wrote: post #23

Earlier quoted context omitted.

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/

>Drivers are paid per mile

That doesn't seem to be the majority here.

Re: Can a single car break a traffic jam?

#98

Post by thatcat » Sat, Apr 30, 2016, 3:44 PM UTC

xixixao wrote: post #96

iwwr wrote: post #94

Earlier quoted context omitted.

Still, instead of wearing out the cheap & quick to replace break pads, you wear out your transmission.

If you are shifting correctly that is not the case. The "breaking" is achieved by the engine, the wear on the transmission is the same as when you are stepping on the gas.

It also cause pressure waves in the exhaust system since you're using the vacuum forming in the engine to slow you down, which is more noticable at low rpms due to the slowing of the positive exhaust pressure changing to intake vacuum frequency. Going from acceleration to engine braking at low rpms, such as in traffic jams, has caused a weaken seam in my exhaust system to break.

Re: Can a single car break a traffic jam?

#99

Post by rando18423 » Sat, Apr 30, 2016, 5:53 PM UTC

SilasX wrote: post #40

maxerickson wrote: post #34

Earlier quoted context omitted.

Tariffs. If people want access to a congested zone, charge them for it. Dynamically adjust the tariff based on the level of congestion. Of course people hate this and wail that it isn't fair, but it is among the more fair solutions to the immediate problem and inflicting traffic jams is probably not a good way to address economic inequality.

Agree. Tolls (assuming they means the same thing as tariffs) can also create the critical mass necessary for commuter bus lines to work, thereby allowing people to spend only a little more than they do now on commuting but get there faster since the roads are cleared. (The per person effective toll would be lower on a bus, even if they are charged by size.) But they would have to be much higher than in most proposals…

So the poor person who needs to get to the doctor should take the slow lane, and the rich person who wants to get to the next bar faster should take the fast lane? Public utilities INTENTIONALLY are not and should not be run according to the principles of profit maximization.

Re: Can a single car break a traffic jam?

#100

Post by colejohnson66 » Sat, Apr 30, 2016, 6:06 PM UTC

seizethecheese wrote: post #33

GigabyteCoin wrote: post #23

Earlier quoted context omitted.

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 are generally not allowed in the left lane on the freeway, and the right must be a nightmare of merging for semi-trucks in traffic.

Not to mention that if the right lane is an "exit only" lane, merging a truck over a lane is pretty hard. No one wants to leave enough room. Or when you do leave enough room, some idiot sees that giant opening and moves into it.