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Hard-braking events as indicators of road segment crash risk

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Re: Hard-braking events as indicators of road segment crash risk

#361

Post by CGMthrowaway »

presidentender wrote: post #20

I got one of those dongles from my insurance company that plugged into the ODB2 port and reported my driving habits. I was a bad driver. It would frequently beep at me to let me know that I had braked too hard. I was mystified. "What should I have done differently," I'd think, as I raged at the objective machine that judged me so. The next time my brother came to visit, he called mom. "Oh, and presidentender is a goo…

>I'd follow the drivers in front of me too closely

Best trick for managing this is to "drive through" the car in front of you. That is, judge your following distance based not on the car in front of you, but on the car in front of THEM.

And you don't have to "drive through" all the way down the road - it only takes one car/one level of abstraction for this approach to yield really great benefits, try it if you don't believe me.

Re: Hard-braking events as indicators of road segment crash risk

#362

Post by CGMthrowaway »

Sohcahtoa82 wrote: post #252
c22 wrote: post #240

Earlier quoted context omitted.

It seems like a tragedy, but actually it can be a boon as long as you travel in neither the leftmost nor rightmost lane . The majority of the traffic entering your buffer will be exiting your buffer out the other side as soon as they can, so you can just chug along at a (greatly reduced, but) consistent speed. Meanwhile, the traffic to either side of you is in standstill, paralyzed by your bow wake.

It's wild to me how often the left lane is not the fastest lane. I've had times where the right lane ends up being the fastest. On I-5 near Woodburn, OR, it's 3 lanes. So many drivers, including truckers, will often stay out of the right lane entirely to avoid being caught up in traffic coming on/off. Meanwhile, the left lane is going 5 mph under the limit because there's a left-lane camper somewhere miles ahead. So…

>It's wild to me how often the left lane is not the fastest lane.

Reasons vary, but a lot of the time it can be explained by left exits/splits ahead on the highway. Which some may call poor design.

Re: Hard-braking events as indicators of road segment crash risk

#363

Post by redanddead »

presidentender wrote: post #20

I got one of those dongles from my insurance company that plugged into the ODB2 port and reported my driving habits. I was a bad driver. It would frequently beep at me to let me know that I had braked too hard. I was mystified. "What should I have done differently," I'd think, as I raged at the objective machine that judged me so. The next time my brother came to visit, he called mom. "Oh, and presidentender is a goo…

Insurance erotica right here lol

Re: Hard-braking events as indicators of road segment crash risk

#364

Post by Sohcahtoa82 »

Uvix wrote: post #355
crest wrote: post #291

Earlier quoted context omitted.

It's wild to me that it's allowed and accepted to overtake on the right on US highways.

It's generally not allowed , but that doesn't stop people just like the speed limit doesn't stop them.

> It's generally not allowed

Common misconception, actually.

There is not a single state in the USA where using the right lane to pass slower traffic in the left/center lanes is illegal. It is allowed everywhere.

Re: Hard-braking events as indicators of road segment crash risk

#365

Post by CGMthrowaway »

OneOffAsk wrote: post #140

Aim to make the road laminar. Every time you hard brake, you're causing the milk jug to glug, making a ripple of entropy as momentum turns to heat from your brakes and those behind you, sometimes in perpetuity. I learned this while doing a 1.5hr daily commute in a Subaru with a clapped out manual transmission. I wanted to conserve energy shifting, but realized I was now participating in large choreographed dance of "…

Of course braking/change in velocity creates waves. But this effect is overemphasized in my opinion. Locally analyzed, traffic can be simplified incredibly by observing that a lane's maximum throughput is simply given by following spacing, measured in time.

If drivers are using a 2 second following distance, commonly taught in driving school, then max throughput is simply

  1 car / 2 sec
If you double following distance, you halve the throughput. If you halve following distance, you double your throughput. The throughput of a (full, i.e. rush-hour) road has nothing to do with speeds of people driving, and everything to do with following distance.

Re: Hard-braking events as indicators of road segment crash risk

#366

Post by Sohcahtoa82 »

crest wrote: post #291
rootusrootus wrote: post #274

Earlier quoted context omitted.

> On I-5 near Woodburn, OR The section of I-5 between Portland and Salem is absolutely psychotic, and I have never been able to reason out exactly why . It consistently has a left lane jammed with angry people going at or below the speed limit, a fairly normal center lane filled with cruisers, and a mostly empty right lane with the occasional big rig and regular very-high-speed cars expressing their frustration with…

It's wild to me that it's allowed and accepted to overtake on the right on US highways.

The alternative is that you're stuck going 10+ mph under the limit because of a left lane hog.

Banning passing on the right only works if keep-right-except-to-pass laws exist and are thoroughly enforced. Most states in the USA don't have keep-right laws, and those that do, it's never enforced, so many people don't even know it's actually the law.

EDIT: US-26 westbound immediately outside downtown Portland is notorious for left lane campers. The limit is 50 mph, but without fail, there's some moron going 40 mph in the left lane. You wanna go slow? Fine, but do it in the right lane where you belong.

Re: Hard-braking events as indicators of road segment crash risk

#367

Post by ehnto »

crazygringo wrote: post #331
ehnto wrote: post #326

Earlier quoted context omitted.

Slow down a bit to create another buffer. You can even do this before they have merged, as part of the bit where you allow them to safely merge. I think if you reflect a bit you'll find you are being the same kind of person as them, if you are getting angry that you have to slow down and give up space for someone else. I understand some people can be aggressive though, that can be frustrating regardless of the outcom…

I don't think you're understanding. The point is that 20 people in a row will take advantage of your buffer to slow you down again and again and again, which makes you get to your destination later... because they're being selfish to get somewhere faster, and you're not so you get to where you're going slower . We're not talking about where they're changing lanes to take the next exit. We're talking about where your…

I understand perfectly, 20 years driving, I think people just don't like that the safe answer is to be slow. You will not fix others behaviour, so your options are be slow and generous, get out of the chaotic lanes (unless that's all of them), or join them and be aggressive, claim space, be stressed and annoyed your whole trip.

There is no solution to traffic here sorry, this is more about managing your own frustration and expectations when faced with people at their worst, in the worst form of transport.

The total, confirmed, 100% effective solution is to never commute by highway during peak hours, but few get that option.

Re: Hard-braking events as indicators of road segment crash risk

#368

Post by Barbing »

CGMthrowaway wrote: post #359
crazygringo wrote: post #340

Earlier quoted context omitted.

> If you choose to go in the fastlane in traffic you should understand that it will have people who do not care about the following distance as much and are just trying to go as fast as possible. It's not about choosing to go in the fast lane. It's about the fact that in heavy traffic, you have no idea which lane will be fastest, because they're all heavy and which one is fastest keeps switching. > I have found that…

This is a long thread of people talking past each other. The bottom line is simply this: if you want to drive with a larger-than-average following distance (call it whatever you want, a safety buffer, a "proper" following distance, the point is it is a distance less than the average following distance of the other drivers on the road) then you have to accept that you will not be able to drive at the same speed as the…

>It can be psychologically frustrating

True, though-

I like being a traffic hacker--come on in, plenty of room!

Re: Hard-braking events as indicators of road segment crash risk

#369

Post by redanddead »

geocrasher wrote: post #68
avidiax wrote: post #9

Earlier quoted context omitted.

Some amount of that is inevitable, but there is another level of defensive driving where you anticipate poor behavior and arrange that it won't cause an accident. Have a look at a few dash cam accident videos [1]. There are many maladaptive patterns of behavior, but a frequent one that the average good driver can improve on is limiting speed on two occasions: when approaching a blind spot, and when passing stopped or…

I learned next-level defensive driving by bicycle commuting to work 5.5 miles each way on busy roads in rush hour traffic. On a bicycle you're invisible, and if you expect any less, you're going to get hurt. As it was, I had some very very close calls- at least one of them had the potential to be fatal. Ironically, the only time I ever crashed was my own fault. But now even when in a car, I retain that "I'm invisible…

>I learned next-level defensive driving by bicycle commuting to work 5.5 miles each way on busy roads in rush hour traffic

please stop doing that geocrasher

Re: Hard-braking events as indicators of road segment crash risk

#370

Post by redanddead »

mecsred wrote: post #40
munificent wrote: post #31

Earlier quoted context omitted.

How does one not already know that they had a hard braking event? Surely the jamming their foot on the brake pedal and the rapid deceleration would send an even more obvious signal than playing a chime?

Obviously people know, but theres no impulse to introspect on why or how. Knowing that someone else knows you had a hard braking event taps in to our social brains to provide a much stronger response to the event. When we know people are watching we're more likely to try and justify our behaviour.

that is fascinating
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