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How UPS trucks saved millions of dollars by eliminating left turns

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Re: How UPS trucks saved millions of dollars by eliminating left turns

#71

Post by lorenzhs »

jack9 wrote: post #64
lorenzhs wrote: post #58

Earlier quoted context omitted.

According to Wikipedia [1], "as of 1992, right turn on red is governed federally by 42 U.S.C. § 6322(c)", which reads [2]: > Each proposed State energy conservation plan to be eligible > for Federal assistance under this part shall include [...] > a traffic law or regulation which, to the maximum extent > practicable consistent with safety, permits the operator of a > motor vehicle to turn such vehicle right at a red…

This is not "governed federally". Making a state eligible for Federal assistance is not the same as being a legal requirement. How you confuse these things is an example a simple comprehension failure or possibly someone who doesn't understand US law to any degree. https://en.wikipedia.org/wiki/Turn_on_red shows a handy little map in the bottom right highlighting the differences between states.

The portion you take issue with is a quote from the same article that you're referring to, and clearly marked as such. I'm sorry that your "comprehension failure" insult backfired.

By the way, the map on the bottom right is for left turns on red, which isn't the topic here.

Re: How UPS trucks saved millions of dollars by eliminating left turns

#72

Post by pitaj »

koenigdavidmj wrote: post #65
TruthSHIFT wrote: post #34

Earlier quoted context omitted.

Georgia has this too. Who doesn't have this?

In Washington we are advised pretty strongly that Oregon has this but California and Idaho very much do not. (Incidentally, highway on-ramps are considered one way streets for the purpose of this law.)

You're wrong about Idaho. Here's a PDF source[1] of the official driving manual. Check out Turning At a Red Light on page 35.

[1] http://itd.idaho.gov/wp-content/uploads/2016/06/driver_manua...

Re: How UPS trucks saved millions of dollars by eliminating left turns

#73

Post by zebrafish »

dec0dedab0de wrote: post #50
zebrafish wrote: post #37

Earlier quoted context omitted.

when the idea is baked into how your whole traffic system operates, you don't have these issues. People turning right have the same right-of-way as people going straight through an intersection. People turning left must wait for all traffic to clear from the opposing lane before turning. As for someone to your left going straight thru the intersection... you, turning right, must yield to those going straight. However…

People turning right have the same right-of-way as people going straight through an intersection. No they don't, They must come to a complete stop and yield to all traffic, including people turning left. At least in NJ, I don't know about other states. http://www.state.nj.us/mvc/pdf/Manuals/drivermanual.pdf

or someone who comes from your front mau turn left?

so I guess you're right in the scenario that one direction has a green light with no green arrow and the opposite direction has a red light, but how often does that scenario exist?

If both directions have a green light, left-turners yield to right-turners because of traffic behind the right-turners and stop signs are always turn based.

Re: How UPS trucks saved millions of dollars by eliminating left turns

#74

Post by mnarayan01 »

dec0dedab0de wrote: post #50
zebrafish wrote: post #37

Earlier quoted context omitted.

when the idea is baked into how your whole traffic system operates, you don't have these issues. People turning right have the same right-of-way as people going straight through an intersection. People turning left must wait for all traffic to clear from the opposing lane before turning. As for someone to your left going straight thru the intersection... you, turning right, must yield to those going straight. However…

People turning right have the same right-of-way as people going straight through an intersection. No they don't, They must come to a complete stop and yield to all traffic, including people turning left. At least in NJ, I don't know about other states. http://www.state.nj.us/mvc/pdf/Manuals/drivermanual.pdf

I believe the GP is saying that they have the same right-of-way as if they were going straight. Admittedly, the difficulty in talking about this stuff precisely does leave me wondering if some people ITT are total menaces on the roads.

Re: How UPS trucks saved millions of dollars by eliminating left turns

#75

Post by theonething »

dorfsmay wrote: post #21
mstade wrote: post #8

> In the US, and other countries where you drive on the right side of the road, right turns are free, but for a left turn you need to wait for a green light. I don't know of any other country than the US where turning right on red is allowed, unless there's specific signage or additional traffic lights to allow it. Indeed, the turn-on-red rule in the US seems to work inverse to how I've seen it elsewhere – i.e. it's…

Turning right on red is one of those idea that once you've been exposed to it you wonder why isn't everybody adopting it... A similar idea is the train system in Munich where they built their platforms such that they can open doors on both sides, making one side of the train the exit, and the other side the entrance. Ever since I saw that, every single time I wait for people getting off a crowded train, I wonder "Why…

This is OT but do others have this experience?

You're a pedestrian at an intersection and patiently waiting for the crosswalk signal to flash walk because you want to be safe and not jaywalk. As soon as it flashes walk, a "right turner" comes zooming in and proceeds to take their right. Either they abruptly stop when they finally notice me or they don't and just roll on through and I have to jump back on the sidewalk to avoid them. I try to intentionally wait in a position that is very visible to the right turners and it still happens.

I don't feel safe legally crossing the street. It sucks.

Re: How UPS trucks saved millions of dollars by eliminating left turns

#76

Post by euyyn »

jweir wrote: post #44
dorfsmay wrote: post #21

Earlier quoted context omitted.

Turning right on red is one of those idea that once you've been exposed to it you wonder why isn't everybody adopting it... A similar idea is the train system in Munich where they built their platforms such that they can open doors on both sides, making one side of the train the exit, and the other side the entrance. Ever since I saw that, every single time I wait for people getting off a crowded train, I wonder "Why…

NYC has no right on red. After getting used to I loved it. Now I live in another city with right on red and a fair amount of bike and pedestrian traffic. Turning right on red means looking out for cars, people, bikes and having the pressure of a car behind you - perhaps honking because it wants you to go.

> having the pressure of a car behind you - perhaps honking because it wants you to go

Don't let assholes stress you. The honk shouldn't be used for that, plus you can take as much time as you need to make sure you're driving safely.

Re: How UPS trucks saved millions of dollars by eliminating left turns

#77

Post by rogerbinns »

camiller wrote: post #68
helipad wrote: post #19

Earlier quoted context omitted.

My brother came to Michigan to visit from the UK. After a few days he said: "So, I can go on a red light for a right turn, but sometimes I have to wait at a green light for a left turn?" It was then I realised how peculiar the signals in the US can be.

Flip side, having driven in England 20+ years ago. In England, when stopped at a red they politely blink a yellow light when your stop light is about to turn green. In the US not only do we not do that, but many localities put extended shields around the lights, polarized lenses, etc. To prevent you from knowing when your light is about to turn by observing the lights for the perpendicular street. In other words... E…

The majority of cars in the UK are manual (ie not automatic) gears. Consequently that forewarning gives the driver something to do as it does take a second or two to get into gear.

Re: How UPS trucks saved millions of dollars by eliminating left turns

#78

Post by jventura »

lorenzhs wrote: post #42
jventura wrote: post #32

Earlier quoted context omitted.

> Turning right on red is one of those idea that once you've been exposed to it you wonder why isn't everybody adopting it... Because someone who comes from your left may go forward, or someone who comes from your front mau turn left? Where I live, we do not assume that we can turn right on red lights. Where and when that's possible, we have a blinking yellow light (basically meaning proceed with caution)..

Turning right on a red light is only permitted after establishing that it is safe to do so. Obviously you can't just assume that it'll be fine to go. The difference between your country and the US is the default value: do you have a blinking light permitting it in some places, or a sign prohibiting it where it would be unsafe?

Blinking light permiting it when it is considered safe to turn (with caution).

Re: How UPS trucks saved millions of dollars by eliminating left turns

#79

Post by euyyn »

lnanek2 wrote: post #57
dx034 wrote: post #24

Earlier quoted context omitted.

Wasn't Waze known to prefer routes that consisted of an incredible amount of left turns and small roads? Haven't checked if they changed the algorithm. Found that Google Maps is hard to beat on their preferred route usually.

At least in NJ, Google Maps typically does a terrible job. When I go from my home to Costco, I take one small road to the highway, take the highway, get off, and take one small road to Costco. It's very fast and easy. Makes a big L on the map, basically. Google Maps ignores the highway and has me make twenty alternating left and right turns on tiny backroads. It's grueling, a lot of work, and you can't even go fast o…

That's odd, as Google Maps optimizes on duration, not distance: It takes speed into account.

Maybe it's not taking into account how fast can cars make each of the turns?

Re: How UPS trucks saved millions of dollars by eliminating left turns

#80

Post by euyyn »

lorenzhs wrote: post #52
amelius wrote: post #4

Does typical navigation software assign the same cost to a left turn as a right turn?

Since you need turn restrictions if you want to compute routes that users can actually follow, adding different costs for different kinds of turns (left, right, U-turn) is easy. See my other comment in this thread on the challenges associated with incorporating turn costs and restrictions in gerenal: https://news.ycombinator.com/item?id=13616676

> Incorporating turn costs into route planning is actually not that easy! [I]t doesn't play well with many speed-up techniques.

+

> Since you need turn restrictions if you want to compute routes that users can actually follow, adding different costs for different kinds of turns (left, right, U-turn) is easy.

Does this mean all those speed-up techniques don't produce routes that are actually allowed? What's the point of developing them?

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