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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

#411

Post by kqr »

frogulis wrote: post #333
chausen wrote: post #222

Earlier quoted context omitted.

It brings me peace to see other people thinking this way. You should be an active participant on the highway, making decisions to maximize flow. Leaving space so people can merge, controlling speed to smooth slowdowns, anticipating traffic patterns, etc. All of the people tailgating are contributing to the congestion. https://youtu.be/iHzzSao6ypE

Funny that I could guess that the link would be to that CGP Grey video :D Adam Something has a video responding to it that's worth watching too: https://www.youtube.com/watch?v=oafm733nI6U

"Turning urban areas into obstacle courses for pedestrians" was an excellent way to phrase that problem!

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

#412

Post by Muromec »

ehnto wrote: post #367
crazygringo wrote: post #331

Earlier quoted context omitted.

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 frustrati…

Thanks for writing this, it reminded of how unfun driving really is. I realised how blessed I am now with not having to drive anywhere anymore.

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

#413

Post by erpellan »

maerF0x0 wrote: post #219
Sohcahtoa82 wrote: post #213

Earlier quoted context omitted.

> vehicle changes lanes in front of you; I will never understand why this is so rage-inducing for people. Changing lanes is a necessary part of navigating, even during busy traffic. People on an on-ramp will need to get in front of somebody . People needing to move back to the right because their exist is coming up will need to get in front of somebody . Your lane is not a birth right. Let people merge. > you slow do…

It's frustrating because someone is taking your safety buffer as their opportunity to travel faster. And it results in you having to travel slower and slower to maintain the gap that is constantly consumed, tragedy of the commons style, by opportunists.

But you’re not getting slower and slower for every car. Lets say 100 cars pull in front of you, and let’s be say each car adds 5 metres of space, so you have 500 metres of ‘lost’ space to regain.

At 30 mph how much later will you be? 37 seconds.

I’ll take that trade.

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

#414

Post by vincston »

OptionOfT wrote: post #138
mountain_peak wrote: post #46

Earlier quoted context omitted.

Maintaining a safe following distance is incredibly challenging on busy freeways where hard braking is often 'required'. Most people have likely found themselves in this situation: vehicle changes lanes in front of you; you slow down to maintain a safe following distance, another car sees a gap and changes lanes in front of you. Repeat for your entire commute. Incredibly frustrating, and I've driven all over North Am…

> North America Having driven all over NA, and Europe, I find it more prevalent in NA. Less distance, more people in large pickups throwing their weight around to make someone move out of the way. And a design of giant freeway interchanges that require shifting lanes. E.g. on the 405 in CA. 7 lines going South from the Valley towards Santa Monica. That's 7 lanes you need to cross if you're in the HOV lane.

Honestly imo the driving license requirements and the respective fines for violations is too low. Rigid rules generally improve the traffic flow. But as soon as someone just doesnt care, the system breaks down.

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

#415

Post by dgunay »

WarmWash wrote: post #29
pavel_lishin wrote: post #4

Earlier quoted context omitted.

My mom had a device installed in her car to get a discount on her insurance, and she was always upset at the hard braking thing - whenever she did it, it was because another car was doing something unsafe that she couldn't control, like pulling out in front of her.

If you take a seasoned motorcycle rider and put them in one of those dashcam subs, they'll rip their hair out. Most people have near zero defensive driving skill, and view someone pulling out in front of them as "nothing I could have done", when the dashcam shows the offending driver showed 5 signs of pulling out ages before the accident occurred.

Very true. There is a "body language" to driving. I can often predict when someone will change lanes before they ever turn their signal on (if they even do that) by the way their speed changes and they drift a bit in their lane as they shift their eyes to their mirrors.

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

#416

Post by rramadass »

rramadass wrote: post #258
duncangh wrote: post #215

Earlier quoted context omitted.

Driving and living in Atlanta after living in Charleston and Raleigh felt like transitioning from a modern cooperative society to an island of cannibals. The amount of aggression needed to change lanes largely regardless of attempts to signal good faith and politeness is baffling. Driving is a fascinating ritual with vastly differing norms across regions. It would be interesting to learn if anthropologists have studi…

> Driving is a fascinating ritual with vastly differing norms across regions. It would be interesting to learn if anthropologists have studied this And Psychologists! Reading the comments in this thread is quite amusing. As a driver in India, i can tell you anything goes as long as you don't get into an accident (which may/may-not kill you) or get caught by the police. No rules matter and the only goal is to "one-up"…

Addendum:

Drive in India and you will understand mathematical concepts of Chance/Randomness/Probability/Non-determinism/Game Theory/etc. along with philosophical concepts of Fate/Destiny/Providence/etc. in so direct and visceral a manner that you will never forget the lessons. Sissified countries with rules and regulations for driving can never give you such direct knowledge.

Game Theory - https://en.wikipedia.org/wiki/Game_theory

Game of Chicken - https://en.wikipedia.org/wiki/Chicken_(game)

The game of chicken models two drivers, both headed for a single-lane bridge from opposite directions. The first to swerve away yields the bridge to the other. If neither player swerves, the result is a costly deadlock in the middle of the bridge or a potentially fatal head-on collision. It is presumed that the best thing for each driver is to stay straight while the other swerves (since the other is the "chicken" while a crash is avoided). Additionally, a crash is presumed to be the worst outcome for both players. This yields a situation where each player, in attempting to secure their best outcome, risks the worst.

How to learn One-upmanship/Gamesmanship:

The British author Stephen Potter actually wrote a manual on the practice of such games titled The Theory and Practice of Gamesmanship (or the Art of Winning Games without Actually Cheating) which sissies can study to become strong - https://en.wikipedia.org/wiki/Gamesmanship

For the even more sissified sissies who do not want to read a book, there is a documentary titled School for Scoundrels Or How to Win without Actually Cheating) which is very instructive - https://en.wikipedia.org/wiki/School_for_Scoundrels_(1960_fi...

Disclaimer: I am not responsible for the consequences if the above emboldens you to act in such a manner in your specific context.

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

#417

Post by paganel »

chausen wrote: post #222
Sohcahtoa82 wrote: post #213

Earlier quoted context omitted.

> vehicle changes lanes in front of you; I will never understand why this is so rage-inducing for people. Changing lanes is a necessary part of navigating, even during busy traffic. People on an on-ramp will need to get in front of somebody . People needing to move back to the right because their exist is coming up will need to get in front of somebody . Your lane is not a birth right. Let people merge. > you slow do…

It brings me peace to see other people thinking this way. You should be an active participant on the highway, making decisions to maximize flow. Leaving space so people can merge, controlling speed to smooth slowdowns, anticipating traffic patterns, etc. All of the people tailgating are contributing to the congestion. https://youtu.be/iHzzSao6ypE

> making decisions to maximize flow

Good driving instructors make you aware of that early on, at least mine did.

I'm not saying that I'm a good driver, because I make mistakes like any other driver out-there, it's just that I oftentimes go with the "maximize the flow" thing instead of just following my individual "well-being" as a driver as a result of what my driver instructor told me some years ago.

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

#418

Post by mistercheph »

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…

60 (20*3) car lengths at 20 mph is 30 seconds

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

#419

Post by fransje26 »

pinkmuffinere wrote: post #342
kqr wrote: post #165

Earlier quoted context omitted.

Not only are you less likely to crash -- you're less likely to cause a crash ten cars behind you. This diagram changed how I think about following distance: https://entropicthoughts.com/keep-a-safe-following-distance

I find this diagram _incredibly_ hard to read. I’m pretty sure I understand the phenomenon he’s describing — without safe following distances, car n+1 must break more aggressively than car n in order to avoid a collision, so given a long enough chain of non-safe followers, a collision is guaranteed. But either I am dumber than I’d like, or that plot is terrible.

The plot is trying to illustrate the solution to an equation that is quite similar to Burger's equation, with a strong dependency on space and time. That's not easy to do in a single, static image.

When the characteristics meet (when the lines overlap), you get a shock wave. Or, in the current context, a traffic collision.

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