BurlOak
Senior Member
If I would have designed the old system, red and green would be reversed. If the system fails, gravity would lower the arm to be more or less vertical. It is safer to make vertical a stop and horizontal a go.
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Roads: Traffic Signals
- Thread starter reaperexpress
- Start date
Johnny Au
Senior Member
There's also the Wigwag:In the early days of the railway, they used semaphore signals to indicate how trains should proceed or not. These days, they switched over to using traffic signals similar to what we have at street intersections.
That's fine, when the trains run on private right-of-ways, away from motor traffic. Not so fine where the signals could get mixed up.
Note how the position of the semaphore arm are similar to transit signals used in other counties.
W. K. Lis
Superstar
Wouldn't it be better if we replace this sign
with a nearside traffic signal?
Right where the motor vehicles should actually be stopping?
with a nearside traffic signal?
Right where the motor vehicles should actually be stopping?
EastYorkTTCFan
Senior Member
There's also the Wigwag:
that's for a railroad crossing it used to be used instead of the lights we have now.
reaperexpress
Senior Member
We already do that for signals where the stopping location is unusually far back.
Harbourfront Centre at Queens Quay northbound. Image from Streetview
Queen at Wineva westbound. Image from Streetview
In locations such as the Netherlands where signals are only on the near side, they are extremely effective at enforcing correct stopping locations. But in locations where they are used in addition to far-side signals, they are only marginally effective. If we were starting from scratch, I'd probably support near-side signals but at this point it's not worth switching.
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W. K. Lis
Superstar
The near-side signals would be a good addition, especially on large or busy intersections. The far-side signals sometimes gets blocked by high trucks blocking the view.
coopEng
Active Member
The near side signals you normally see are to provide an extra signal in areas where visibility of the far side signals is reduced - typically at hills, turns that lead to intersections, etc.
W. K. Lis
Superstar
New York City Council Unanimously Passes Bill to Expand Pedestrians’ Right of Way
See link.
Today’s legislation ensures that pedestrians who enter a crosswalk during the flashing “Pedestrian Change Interval” have the right of way under New York City law. Image: DOT
See link.
Today’s legislation ensures that pedestrians who enter a crosswalk during the flashing “Pedestrian Change Interval” have the right of way under New York City law. Image: DOT
Johnny Au
Senior Member
When I visited Manhattan, almost everyone there jaywalked across the east-west streets anyways (if there is no incoming traffic).
reaperexpress
Senior Member
Yeah I noticed the same. And after about a day, I started doing it too. Telling people to wait when there's clearly no one crossing their path is a surefire way of turning law-abiding citizens into rule breakers.
The problem in NYC is that all the signals are fixed-time (simply cycle through a pre-timed sequence), so they don't actually know whether or not there is a car approaching which would conflict with pedestrians.
In contrast, the majority of intersections in Toronto have vehicle detectors for side streets. But the vehicle and pedestrian signals are tied together: if a pedestrian presses the button the vehicle signal will get a green too - even if there is no vehicle there. Which means that there are often times when the main street pedestrians get a Don't Walk signal, even though there is no car crossing their path.
Which got me thinking: what if we used the vehicle detectors to only bring up the vehicle green when there's actually a vehicle waiting? If at the end of the main street pedestrian countdown there is no vehicle waiting on the side street, the main street pedestrian signal would go back to Walk for the side street phase.
This setup would be most appropriate at signals which exist primarily to allow pedestrians to cross the street (i.e signals with many pedestrians but few vehicles crossing the main street). There are a large and increasing number of such signals in the old city, since many councillors have "adding a signal at _x_ to help people cross the street" as a pet project.
One example is King & Stanley Terrace (streetview here), where the side street isn't even a road, it's a laneway.
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Johnny Au
Senior Member
That is a great idea, reaperexpress.
Note that I am used to crossing streets Manhattan-style, even a few years before visiting NYC for the first time. Even in Toronto do I cross Manhattan-style.
I believe that vehicle detectors should be installed in more cities. Manhattan would benefit greatly (though it would be very expensive to do so there).
Note that I am used to crossing streets Manhattan-style, even a few years before visiting NYC for the first time. Even in Toronto do I cross Manhattan-style.
I believe that vehicle detectors should be installed in more cities. Manhattan would benefit greatly (though it would be very expensive to do so there).
reaperexpress
Senior Member
I finally got around to writing a more detailed explanation for the "placebo" pedestrian buttons, including some suggestions for how to make their purpose more clear:
https://ontariotrafficman.wordpress.com/2016/10/03/do-pedestrian-buttons-actually-work/
When people find out I have a working knowledge of traffic signals, this is often the first question they ask. “When I press the button, does it actually do anything to the signal timing?” The short answer is: sometimes. Because there’s more to pedestrian buttons than just getting a walk light to cross the street.
There’s two parts t0 the answer here, which are:
1. There are some pedestrian crossings where someone needs to press a button for the walk light to be displayed, and other crossings where there is no need for anyone to press a button,
2. Pedestrian buttons are being installed at all pedestrian crossings, whether or not those buttons actually have an effect on signal timing.
Why doesn’t the walk light just come on all the time?
At a typical intersection between a main street and a side street, the pedestrian signal along the main street defaults to walk, so it doesn’t matter whether or not anyone presses the button. But to get a walk signal along the side street, you actually need to press the button. If there are cars waiting and nobody presses the pedestrian button, the vehicle signal will display Green but the pedestrian signal will remain in Don’t Walk.
If the walk signal came on every time the light turned green, it could cause unnecessary delay to perpendicular traffic in the situation when there are only a few cars and no pedestrians. For example, a pedestrian crossing across a 7-lane road might require a minimum of 28 seconds of green (7 seconds of Walk and 21 seconds of Flashing Don’t Walk). But in the absence of a pedestrian call, the green duration for side streets can respond in real-time to the actual amount of vehicle demand, so if there are only a couple cars waiting, the green light could be as short as 7 seconds. Varying the green duration based on side street vehicle demand means that people travelling along the main street aren’t kept waiting any longer than needed*.
It’s for this same reason that often pedestrian crossings along a main road will displayWalk regardless of whether anyone presses the button. Due to the anticipated volume of vehicle traffic, the signal is going to provide more than enough time to walk across the side street anyway, so the pedestrian signal might as well display Walk even if there wasn’t anyone waiting to cross at the start of the green. Displaying Walk as much as possible avoids any unnecessary delay for people who show up after the light has already changed to green.
Why are all crossings getting pedestrian buttons?
Eventually, all pedestrian crossings in the City of Toronto will have pedestrian buttons, regardless of whether the pedestrian button would have any effect on signal timing. The same is also true in many other jurisdictions across the province. This is because buttons are the way of activating the Accessible Pedestrian Signal (APS) audible tones, which are gradually being installed at all traffic signals.
Originally, APS was on whenever the walk light was on, so it didn’t need any buttons to operate. But after a number of noise complaints from nearby residents, the current system was introduced, where the APS sounds would only be played when someone presses and holds the pedestrian button for 3 seconds (at which point the button makes a tick noise to indicate the APS call was received).
Making sense of pedestrian buttons
The problem with having buttons that don’t affect signal timing is that when some people discover that there are pedestrian buttons which have no effect on signal timing, they come to the conclusion that all pedestrian buttons are placebos. This is a problem, because there actually are crossings where one does need to press the button to get a walk light.
The solution to this problem is very simple. Each pedestrian button should indicate whether one needs to press it to get a walk signal, or if it’s only there to call the APS sounds. Variations of this system are implemented in a number of jurisdictions in Ontario. In the City of Ottawa, buttons which actually call the pedestrian phase have a sign saying “press this button”, while buttons which only call APS sounds have no sign.
In Ottawa, the buttons without signs are only there to activate APS sounds
But I found that system to not be sufficiently reassuring. Upon encountering a button with no sign, I wouldn’t be certain if meant that I didn’t need to press the button or if the sign had simply fallen off. So I always pressed the button to be sure.
My favourite solution is the one used in Waterloo Region, where buttons which only exist to activate APS sounds have the symbol of a person with a white cane.
“This button only activates the APS sounds”
“You need to push this button to get a Walklight”
This labeling system is a clean and simple way of indicating what pedestrian buttons do (or don’t do), putting an end to the myth of the placebo pedestrian button.
W. K. Lis
Superstar
CITY News video on pedestrian signals: http://bcove.me/anj9oi6u
reaperexpress
Senior Member
It's true that it's technically illegal to enter the intersection during the Flashing Don't Walk. But implying that the reason is to let cars turn? That's just something they made up to give motorists more reasons to get angry while driving. Far from promoting road safety, this video is actually promoting road rage.
The Flashing Don't Walk exists to give pedestrians time to cross the street if they have already started crossing. The design does not expect there to be any time where the crosswalk is clear due to the Flashing Don't Walk. If the City wanted to facilitate right turns, they would keep the walk light to a minimum duration and then display Solid Don't Walk with a right-turn arrow. But they don't do that because the delay incurred to the hundreds of pedestrians would far outweigh the delay saved by motor traffic. To prioritize a few right-turning cars over a much larger number of pedestrians, you would need to consider the time of a car driver to be many times more valuable than the time of someone walking. In addition to being highly offensive, that notion is completely backwards from the objectives of a downtown area.
Yes, obviously if people stand on the curb rather than crossing the street it would be easier for car drivers to turn right. In fact, the best case scenario would be if everyone just stayed home and didn't walk at all.
But if we make walking more inconvenient people aren't just going to stay home. They're going to consider other alternatives, such as driving. And adding another car to the road network will incur far more delay to existing drivers than would the addition of a pedestrian.
This crackdown on pedestrians is the final straw that convinces me that John Tory is not actually interested in examining technically-justified options for solving problems such as congestion. He's just doing a toned-down version of Rob Ford's divide and conquer politics. When he was first elected I truly believed that we would see a change toward evidence-based decision-making, so I am genuinely disappointed.
Until this blitz, no-one knew that entering the crosswalk during Flashing Don't Walk was illegal, so it was a non-issue. It's definitely a problem when the status quo is law-breaking, but in cases such as this where the law is clearly unreasonable the solution is the change the law, not enforce it to the letter.
A few reasons why current writing of the law is unreasonable:
- Flashing Don't Walk (FDW) intervals are timed for the slowest pedestrians. I happen to walk quickly, so I can typically enter the intersection almost halfway through the countdown and still get to the other side before it reaches 0. This does not follow the letter of the law, but it does follow the intent, which is to get pedestrians out of the crossing before the light changes to yellow.
- FDW intervals are supposed to be timed based on the crossing distance. This is true, but in each intersection the FDW duration will always be designed the for larger of the two crosswalks. Usually this doesn't make much difference, but there are some cases where that means that the shorter crosswalk gets massively excessive FDW time. One such example is Queen's Quay Blvd & Spadina Ave/Spadina Loop. The east-west FDW is timed based on the north side crosswalk at Spadina, which is a 28 metre hike across four traffic lanes, two streetcar lanes, a streetcar platform and two corner radii. As a result, the FDW must be about 24 seconds. This same FDW time is applied to the east-west crossing on the south side, which is a mere 8 metre hop across the driveway into 401 Queens Quay. At my walking speed of 1.7 m/s, I could cross 5 times (i.e. 2.5 round trips) in the duration of the Flashing Don't Walk. Expecting people to see a 24 second countdown across a driveway and not cross is well outside the realm of reasonableness.
- Pedestrians already face more delays at traffic signals than vehicles in the same direction, precisely because of the time they take to cross. Let's take a typical downtown intersection such as Dundas & Bay. The crossing distance along Dundas is 21 metres, so the FDW is probably 18. At a minimum, the green time will be 26 seconds (8s Walk + 18s FDW). So according to the current law, there are 26 seconds per cycle (~60 sec cycle in this case) where cars are allowed to enter the intersection, but only 8 seconds where pedestrians are allowed to enter. Imagine the uproar if we cut down the vehicle green to 8 seconds! If people actually obeyed this law, it would take forever to walk anywhere. Instead most people follow the intent of the law and merely aim to clear the crosswalk by the end of the countdown (by all means, ticket people who are still in the crosswalk at the end of the countdown). With my walking speed and my loose interpretation of the law, it means that there are effectively 16 seconds where I could enter the intersection.
- In addition to the specifics above, artificially increasing delay for walking is against the best interest of car drivers. The root cause of traffic congestion is too many cars. It is simply a fact that cars take up way too much space to rely on for urban transportation. Even if there were no pedestrians and cars could turn right as they pleased, there would still be horrible congestion. Because the number of induced new driving trips would more than outweigh the savings from reduced impedance. The only way to resolve the shortage of road space is to get people out of cars and onto sidewalks, bikes or transit vehicles where they take up far less space.
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W. K. Lis
Superstar
Used to be there were no pedestrian signals. People crossed on the green light. People ran on the yellow light. People stopped on the red light.
Then they added pedestrian signals. No countdown. But they were "WALK" during the entire green light. They were "DON'T WALK" on the yellow and red lights.
Then they changed to pictographs. However, they just replaced the words.
With the countdown, what happened? The pedestrians now have less time to cross the intersection (legally speaking). The powers-that-be made it worst for the pedestrians.
Then they added pedestrian signals. No countdown. But they were "WALK" during the entire green light. They were "DON'T WALK" on the yellow and red lights.
Then they changed to pictographs. However, they just replaced the words.
With the countdown, what happened? The pedestrians now have less time to cross the intersection (legally speaking). The powers-that-be made it worst for the pedestrians.