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A Type of Road Junction that Kills Cyclists

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Re: A Type of Road Junction that Kills Cyclists

#91

Post by jdavis703 »

bsder wrote: post #77
Declanomous wrote: post #45

>We must note that there are two parts to the definition of dangerous driving. Firstly the standard of driving must be “far below what would be expected of a competent and careful driver”, and secondly it must be “obvious to a competent and careful driver that driving in that way would be dangerous”. The longer I use the road in any function (cycling, driving, walking, etc), the more I am convinced that the vast majo…

> The longer I use the road in any function (cycling, driving, walking, etc), the more I am convinced that the vast majority of people are not competent drivers. You are almost right. ALL people are incompetent drivers. Driving is a task of 99% boring routine habit punctuated by 1% of moments requiring extreme engagement. Humans are not engineered for these kinds of swings. But computers are. And that's why the takeo…

No one should never really routinely be in a situation where driving requires extreme engagement.

If anyone is in this situation routinely (that means for every hour they drive, 36 seconds is an extreme situation), it means the driving regularly does not meet the conditions of the situation they are in.

For example if someone feels like they are almost always hitting "impulsive" pedestrians, it means they need to drive slower through areas with lots of pedestrians. Likewise if they're frequently taking evasive moves around people driving haphazardly, it means they weren't paying attention to which automobiles appear likely to do something dumb.

Re: A Type of Road Junction that Kills Cyclists

#92

Post by nostrademons »

matte_black wrote: post #4

Wow, after all these years I finally learned the name of this phenomenon, constant bearing decreasing range. I recall a scene in the movie Sin City where two cars crash and the camera was moving in CBDR to the perpendicular car as it zoomed into the impact site. I thought it was a cool shot. Also I’ve almost hit pedestrians several times when they were obscured by my A pillar. Sometimes I wonder if I would have actua…

The Sidewinder missile is based on this phenomena. Early guided missiles attempted to home in directly on the target, bringing the bearing from centerline to zero, but they could never make the math work out right in the guidance system. The Sidewinder was the first to realize that the missile is closing in on the aircraft at some speed, and so really the angle it makes with the plane should be constant, not zero. This simplified the avionics enough to get a reasonably accurate missile.

https://en.wikipedia.org/wiki/AIM-9_Sidewinder#Design

Re: A Type of Road Junction that Kills Cyclists

#93

Post by tim333 »

bdamm wrote: post #17
temp-dude-87844 wrote: post #8

There's a lot of math in this article about blind spots and car pillars and whatnot, but a Google Maps Street View appears to show the terrain and brush blocking the view on approach [1][2], making all of this math largely moot. That the drivers in question didn't even so much as slow down for this approach is beyond reckless, aside from the other lawbreaking that followed. The 'Give Way' sign is idiotic, put a Stop…

Indeed, a stop sign would solve this, wouldn’t it? Simplist & cheapest solution first. The point about the geometry is that it doesn’t matter at which point the driver can see over the hill and brush; they still won’t see the cyclist.

Apparently not. I had a very similar junction outside my house where cars crashed constantly though usually non fatally as it was in a 30 zone. I wrote to the road engineer folk asking for a stop sign and apparently motorists don't take much more notice than of give ways. In the end the cross roads were replaced with two mini roundabouts which have fixed the problem. Physical obstacles are much better at making cars slow down than signs.

Re: A Type of Road Junction that Kills Cyclists

#94

Post by ajmurmann »

jdavis703 wrote: post #82
ajmurmann wrote: post #78

Earlier quoted context omitted.

This is true! It's one of the big reasons I cannot wait for self driving cars. I love driving on empty country roads but feel it's impossible to 100% safely drive on busier roads, especially if you also need to read road signs because you don't know where you are going (what's up with US traffic sighs being covered in text btw.? That's obviously a terrible idea!). I came to this conclusion a few weeks after I had got…

The truck almost certainly had a good reason for stopping. The question then becomes why you couldn't you see what the truck driver had seen (debris in the road, a broken down car, etc). Obviously you can't always see around a large truck, but often times danger can be spotted by looking far ahead. For example coming around a blind cliff I was able to deduce there was a person who would be standing in the middle of t…

That's just a heuristic though. Given humans can't look into multiple directions at once therr is always the chance that something unforseen well happen in the direction you just stopped looking at. If the truck hadn't stopped, maybe the car behind me in the gap I wanted to me into could have accelerated to closer the gap. Unlikely, especially on the Autobahn, but could easily happen in LA.

Re: A Type of Road Junction that Kills Cyclists

#95

Post by nostrademons »

ajmurmann wrote: post #86
nostrademons wrote: post #75

Earlier quoted context omitted.

Roundabouts and 4-way stops are used in different situations - a 4-way stop is typically used in residential neighborhoods or street grids where the roads are only single-lane and the lack of available space prohibits a roundabout.

In Europe the residential area would either 1. Have no signs resulting in the car to the right getting the right of way 2. One road gets a right of way sign and the other road had to yield. I strongly prefer those setups because they are much more fuel efficient. However, I don't think any of that would work in the UD because it would require real driving classes and tests. I had to drive around for close to 20 hours…

In the urban eastern U.S. apartment buildings usually run right up to the road, except a ~ 1-3meter sidewalk. There isn't sufficient visibility to yield safely; both directions have to come to a stop anyway to check for cross traffic.

In the western U.S. (and eastern suburbs) the 4-way stops are largely vestigial; I'd agree that most of them could go away without any loss of safety. Many of the newer neighborhoods are signed that way anyway, though - I just drove through one this morning with 2-way yields.

My driver's ed class was IIRC 36 hours of instruction and 12 hours in the car, with a professional driving teacher. It had an hour long examination putting me through as many challenging situations as possible at the end.

Re: A Type of Road Junction that Kills Cyclists

#96

Post by daxfohl »

mrb wrote: post #69
temp-dude-87844 wrote: post #8

There's a lot of math in this article about blind spots and car pillars and whatnot, but a Google Maps Street View appears to show the terrain and brush blocking the view on approach [1][2], making all of this math largely moot. That the drivers in question didn't even so much as slow down for this approach is beyond reckless, aside from the other lawbreaking that followed. The 'Give Way' sign is idiotic, put a Stop…

« make it a 4-way stop » You may be unaware, but 4-way stop signs are very uncommon outside of the US. In fact, in the UK they have always been formally prohibited by the Department for Transport in 2002. As a European driver, I discovered the existence of 4-way stop signs when I moved to the US, and I have always found them dangerous in a counter intuitive way: drivers are so used to 4-way stop intersections, that t…

That's crazy. I find myself frequently having to pause, look around, make sure, etc (and the pausing and looking around in itself is dangerous) so often because of the discrepancy. But as someone born and raised here I've never considered an alternative, and am shocked that the alternative is so simple!

Re: A Type of Road Junction that Kills Cyclists

#97

Post by afterburner »

mrb wrote: post #69
temp-dude-87844 wrote: post #8

There's a lot of math in this article about blind spots and car pillars and whatnot, but a Google Maps Street View appears to show the terrain and brush blocking the view on approach [1][2], making all of this math largely moot. That the drivers in question didn't even so much as slow down for this approach is beyond reckless, aside from the other lawbreaking that followed. The 'Give Way' sign is idiotic, put a Stop…

« make it a 4-way stop » You may be unaware, but 4-way stop signs are very uncommon outside of the US. In fact, in the UK they have always been formally prohibited by the Department for Transport in 2002. As a European driver, I discovered the existence of 4-way stop signs when I moved to the US, and I have always found them dangerous in a counter intuitive way: drivers are so used to 4-way stop intersections, that t…

The "4-way" or "All-way" addition helps a little ( https://i.imgur.com/dzRksUw.jpg ), but I've made the mistake at least once or twice myself.

Re: A Type of Road Junction that Kills Cyclists

#98

Post by cagey »

swimfar wrote: post #54
u801e wrote: post #36

Earlier quoted context omitted.

The US also tends to overuse stop signs when a yield (give way) sign would suffice. That is, if there is sufficient visibility of approaching traffic, coming to a complete stop is not necessary to safely yield to any conflicting traffic. Also, coming to a complete stop and then proceeding isn't sufficient to properly yield to approaching traffic. In the end, stop signs end up being treated like yield signs. The only…

In the end, stop signs end up being treated like yield signs. This definitely varies based on where in the US you are. In California almost no one comes to a complete stop. (That's probably why rolling through a stop sign is called a "California Roll"). But in many other parts of the country people do, even if there are no cars around.

I know that practice by the name "California Stop"[1]

[1] https://www.urbandictionary.com/define.php?term=california%2...

Re: A Type of Road Junction that Kills Cyclists

#99

Post by jdavis703 »

ajmurmann wrote: post #94
jdavis703 wrote: post #82

Earlier quoted context omitted.

The truck almost certainly had a good reason for stopping. The question then becomes why you couldn't you see what the truck driver had seen (debris in the road, a broken down car, etc). Obviously you can't always see around a large truck, but often times danger can be spotted by looking far ahead. For example coming around a blind cliff I was able to deduce there was a person who would be standing in the middle of t…

That's just a heuristic though. Given humans can't look into multiple directions at once therr is always the chance that something unforseen well happen in the direction you just stopped looking at. If the truck hadn't stopped, maybe the car behind me in the gap I wanted to me into could have accelerated to closer the gap. Unlikely, especially on the Autobahn, but could easily happen in LA.

You're right we can't see or predict everything. I just heard a story where a pilot had to drop a snake out of their small private aircraft while flying over a highway. There was a high likelihood that a driver below had no way of knowing a snake might fall out the sky and perhaps shatter their windshield. Most things that happen on the road though aren't that random.

I once had a bicyclist coming down a curvy mountain road. There was something about their riding that seemed uncomfortable, so I started slowing down. The biker then wiped out and crossed over the yellow line, stopping a few feet from my truck. If I hadn't been proactively scanning and thinking about everything that could go wrong they probably wouldn't have been able to get up, and say "thanks for not running me over."

I don't write this to judge you, or brag about myself. I've made plenty of mistakes myself. This is more a general lesson for people: synthesize all inputs received while driving and take proactive steps to mitigate potential risks.

Re: A Type of Road Junction that Kills Cyclists

#100

Post by tc313 »

ajmurmann wrote: post #86
nostrademons wrote: post #75

Earlier quoted context omitted.

Roundabouts and 4-way stops are used in different situations - a 4-way stop is typically used in residential neighborhoods or street grids where the roads are only single-lane and the lack of available space prohibits a roundabout.

In Europe the residential area would either 1. Have no signs resulting in the car to the right getting the right of way 2. One road gets a right of way sign and the other road had to yield. I strongly prefer those setups because they are much more fuel efficient. However, I don't think any of that would work in the UD because it would require real driving classes and tests. I had to drive around for close to 20 hours…

Most middle- and upper-class Americans take a driver’s education course (like what you’ve described) prior to receiving their driver’s license. In 10 years it won’t even be necessary because nobody’s going to be driving themselves anyway.
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