Pedestrian crossing traffic light that defaults to green for pedestrians

[yand]

Instead of having a pedestrian crossing with a beg button that is by default green for cars, the signal phase defaults to green for pedestrians - then lets cars through once cars are detected on pressure plates or cameras.

This way convenience for pedestrians is hugely increased, but car drivers are still prioritized because it is their presence that stops the pedestrian signal. It also eliminates situations where the pedestrian pushes the beg button, but then a car decides to give way and let the pedestrian jaywalk, then the intersection is stopped dead for no reason when the pedestrian phase finally activates.

To increase convenience for cars, more pedestrian islands could be added to the intersection, even between same direction lanes, to decrease the length of the pedestrian countdown

[SkyPesos]

Since you mentioned that the car signal would be triggered by a pressure plate or camera, instead of by pedestrians, what if the car traffic is so high, that the signal always stays green for cars, and red for pedestrians? Unless you plan for the cars signal to turn back red after some time.

[hotdogPi]

If this is implemented, it should definitely be dependent on time of day.

[CardInLex]

I've seen this before. The term is "Rest-in-walk."  I've seen it primarily in downtown settings. Mainline stays green for cars and peds crossing the side street. When a vehicle is detected on the side street or a ped presses the button to cross mainline, flashing don't walk for mainline begins and the signal cycles to allow side street traffic to go/cross.

[BuildTheRussian]

In my opinion, defaulting some actuated signal intersections, where both roads are equally busy, to all-red with all pedestrian signals displaying "WALK" is a great idea, especially if the sensors are located a few feet away so that if there's no traffic, vehicles would be able to proceed without stopping.
This could be used at night as a safer alternative to the flashing mode. In fact, it already is used in Australia. There, it's known as "dwell-on-red".

[hotdogPi]

In my opinion, defaulting some actuated signal intersections, where both roads are equally busy, to all-red with all pedestrian signals displaying "WALK" is a great idea, especially if the sensors are located a few feet away so that if there's no traffic, vehicles would be able to proceed without stopping.
This could be used at night as a safer alternative to the flashing mode.

The sensors would need to be about 20 seconds away (depending on the size of the intersection) if you want to make sure the intersection is clear of pedestrians when a car gets there. And what if the approaching car turns after being detected?

[BuildTheRussian]

In my opinion, defaulting some actuated signal intersections, where both roads are equally busy, to all-red with all pedestrian signals displaying "WALK" is a great idea, especially if the sensors are located a few feet away so that if there's no traffic, vehicles would be able to proceed without stopping.
This could be used at night as a safer alternative to the flashing mode.

The sensors would need to be about 20 seconds away (depending on the size of the intersection) if you want to make sure the intersection is clear of pedestrians when a car gets there. And what if the approaching car turns after being detected?

I assume you mean if the approaching car was to turn off the road. In that case, the controller could check if the car had reached the intersection sensor, and if not, the system could return to the default "all red" state.

[Bitmapped]

In my opinion, defaulting some actuated signal intersections, where both roads are equally busy, to all-red with all pedestrian signals displaying "WALK" is a great idea, especially if the sensors are located a few feet away so that if there's no traffic, vehicles would be able to proceed without stopping.
This could be used at night as a safer alternative to the flashing mode.

The sensors would need to be about 20 seconds away (depending on the size of the intersection) if you want to make sure the intersection is clear of pedestrians when a car gets there. And what if the approaching car turns after being detected?

I assume you mean if the approaching car was to turn off the road. In that case, the controller could check if the car had reached the intersection sensor, and if not, the system could return to the default "all red" state.

You can't just immediately terminate Walk signals. You have to go through the Flashing Don't Walk sequence and then show Don't Walk before you have conflicting movements. Even with small intersections crossing two lanes, this is normally taking 10 seconds or more. For a car traveling 25mph, that's 366 feet or more away - longer than a block in many downtown areas.

You generally don't see traffic signals rest in a 4-way walk because it imposes long delays on vehicles. Rest in walk for the main street, where you can also serve the majority of vehicular traffic, or if you really want rest in all-red, all-Don't Walk so the signal is ready to go for whatever vehicle or pedestrian triggers it first.

[BuildTheRussian]

In my opinion, defaulting some actuated signal intersections, where both roads are equally busy, to all-red with all pedestrian signals displaying "WALK" is a great idea, especially if the sensors are located a few feet away so that if there's no traffic, vehicles would be able to proceed without stopping.
This could be used at night as a safer alternative to the flashing mode.

The sensors would need to be about 20 seconds away (depending on the size of the intersection) if you want to make sure the intersection is clear of pedestrians when a car gets there. And what if the approaching car turns after being detected?

I assume you mean if the approaching car was to turn off the road. In that case, the controller could check if the car had reached the intersection sensor, and if not, the system could return to the default "all red" state.

You can't just immediately terminate Walk signals. You have to go through the Flashing Don't Walk sequence and then show Don't Walk before you have conflicting movements. Even with small intersections crossing two lanes, this is normally taking 10 seconds or more. For a car traveling 25mph, that's 366 feet or more away - longer than a block in many downtown areas.

You generally don't see traffic signals rest in a 4-way walk because it imposes long delays on vehicles. Rest in walk for the main street, where you can also serve the majority of vehicular traffic, or if you really want rest in all-red, all-Don't Walk so the signal is ready to go for whatever vehicle or pedestrian triggers it first.

Where I live, pedestrian signals have to flash green atleast 3 times before turning red. I don't understand why the US requires it to flash for 10 seconds, even if the street is narrow and it takes 5 seconds to cross.

[hotdogPi]

I don't understand why the US requires it to flash for 10 seconds

I've seen 5-second flashes before in Washington DC, although those had a countdown that covered both the walk phase and the flashing phase.

[kalvado]

In my opinion, defaulting some actuated signal intersections, where both roads are equally busy, to all-red with all pedestrian signals displaying "WALK" is a great idea, especially if the sensors are located a few feet away so that if there's no traffic, vehicles would be able to proceed without stopping.
This could be used at night as a safer alternative to the flashing mode.

The sensors would need to be about 20 seconds away (depending on the size of the intersection) if you want to make sure the intersection is clear of pedestrians when a car gets there. And what if the approaching car turns after being detected?

I assume you mean if the approaching car was to turn off the road. In that case, the controller could check if the car had reached the intersection sensor, and if not, the system could return to the default "all red" state.

You can't just immediately terminate Walk signals. You have to go through the Flashing Don't Walk sequence and then show Don't Walk before you have conflicting movements. Even with small intersections crossing two lanes, this is normally taking 10 seconds or more. For a car traveling 25mph, that's 366 feet or more away - longer than a block in many downtown areas.

You generally don't see traffic signals rest in a 4-way walk because it imposes long delays on vehicles. Rest in walk for the main street, where you can also serve the majority of vehicular traffic, or if you really want rest in all-red, all-Don't Walk so the signal is ready to go for whatever vehicle or pedestrian triggers it first.

Where I live, pedestrian signals have to flash green atleast 3 times before turning red. I don't understand why the US requires it to flash for 10 seconds, even if the street is narrow and it takes 5 seconds to cross.

Idea is that whoever steps on the road before light switched should be able to finish crossing. That includes an elderly lady who cannot run.
It takes about 3 seconds to cross 1 lane. So 3 flashes (5 seconds?) Plus 3-4 seconds of yellow should allow 3 lanes crossing.
For some time,  I lived near the intersection where pedestrian would be crossing 7 lanes, and it actually took them a while to get across. But that is a disaster of an intersection to begin with.

[roadfro]

In my opinion, defaulting some actuated signal intersections, where both roads are equally busy, to all-red with all pedestrian signals displaying "WALK" is a great idea, especially if the sensors are located a few feet away so that if there's no traffic, vehicles would be able to proceed without stopping.
This could be used at night as a safer alternative to the flashing mode.

The sensors would need to be about 20 seconds away (depending on the size of the intersection) if you want to make sure the intersection is clear of pedestrians when a car gets there. And what if the approaching car turns after being detected?

I assume you mean if the approaching car was to turn off the road. In that case, the controller could check if the car had reached the intersection sensor, and if not, the system could return to the default "all red" state.

You can't just immediately terminate Walk signals. You have to go through the Flashing Don't Walk sequence and then show Don't Walk before you have conflicting movements. Even with small intersections crossing two lanes, this is normally taking 10 seconds or more. For a car traveling 25mph, that's 366 feet or more away - longer than a block in many downtown areas.

You generally don't see traffic signals rest in a 4-way walk because it imposes long delays on vehicles. Rest in walk for the main street, where you can also serve the majority of vehicular traffic, or if you really want rest in all-red, all-Don't Walk so the signal is ready to go for whatever vehicle or pedestrian triggers it first.

Where I live, pedestrian signals have to flash green atleast 3 times before turning red. I don't understand why the US requires it to flash for 10 seconds, even if the street is narrow and it takes 5 seconds to cross.

Idea is that whoever steps on the road before light switched should be able to finish crossing. That includes an elderly lady who cannot run.
It takes about 3 seconds to cross 1 lane. So 3 flashes (5 seconds?) Plus 3-4 seconds of yellow should allow 3 lanes crossing.
For some time,  I lived near the intersection where pedestrian would be crossing 7 lanes, and it actually took them a while to get across. But that is a disaster of an intersection to begin with.

The US standard for flashing don't walk time is a function of the crossing distance and an assumed pedestrian walking speed of 3.5 ft/sec. It was formerly 4 ft/sec prior to 2009 MUTCD (and this value can still be used if the controller set up to use the slower time when the pedestrian button is pressed for an extended period), but the slower time was adopted to accommodate an increasingly older population.

So a 60 ft wide street would have a FDW time of (60 ft) ÷ (3.5 ft/sec) ≈ (17.4 sec). This would likely be rounded to 17.5 or 18.

[Mr Kite]

Much of the old world has narrower streets than much of North America. It's also quite unusual to have to cross more than three lanes of traffic before reaching a pedestrian refuge. In North America, you're generally expected to cross the street in one go, no matter how wide and often even when there's a median of some kind.

[Bitmapped]

The US standard for flashing don't walk time is a function of the crossing distance and an assumed pedestrian walking speed of 3.5 ft/sec. It was formerly 4 ft/sec prior to 2009 MUTCD (and this value can still be used if the controller set up to use the slower time when the pedestrian button is pressed for an extended period), but the slower time was adopted to accommodate an increasingly older population.

So a 60 ft wide street would have a FDW time of (60 ft) ÷ (3.5 ft/sec) ≈ (17.4 sec). This would likely be rounded to 17.5 or 18.

Bear in mind, too, that the MUTCD requires that the FDW must be followed by 3 seconds of a steady Don't Walk indication before conflicting movements. (There is an FHWA guidance document online that says it must terminate by the start of the yellow when used with countdown signals, but that's not what's in the 2009 MUTCD.) As a practical matter, unless there's an all-red interval, that generally means FDW ends by the time the yellow starts in many settings.

[BuildTheRussian]

The traffic light intersection near me gives one of the other roads green as soon as the yellow light extinguishes. It's not as bad as it seems, and traffic clears the intersection just before one of the other roads gets green.
There's only a few intersections in my city where all roads have a red light in between phases.

[kalvado]

The traffic light intersection near me gives one of the other roads green as soon as the yellow light extinguishes. It's not as bad as it seems, and traffic clears the intersection just before one of the other roads gets green.
There's only a few intersections in my city where all roads have a red light in between phases.

Isn't there a flashing green at the end of the cycle which effectively acts as US yellow, so yellow can act as US all-red?

[BuildTheRussian]

Yes, most modern traffic lights have flashing green. It's meaning is no different from steady green, however. All it does is tell you the green light is about to turn off and that you should hurry up.
The yellow light, on the other hand, is a "prohibitory" aspect, you aren't permitted to go past it if you can stop safely in time. Most drivers just drive through it anyways.

[jeffandnicole]

In my opinion, defaulting some actuated signal intersections, where both roads are equally busy, to all-red with all pedestrian signals displaying "WALK" is a great idea, especially if the sensors are located a few feet away so that if there's no traffic, vehicles would be able to proceed without stopping.
This could be used at night as a safer alternative to the flashing mode.

The sensors would need to be about 20 seconds away (depending on the size of the intersection) if you want to make sure the intersection is clear of pedestrians when a car gets there. And what if the approaching car turns after being detected?

I assume you mean if the approaching car was to turn off the road. In that case, the controller could check if the car had reached the intersection sensor, and if not, the system could return to the default "all red" state.

You can't just immediately terminate Walk signals. You have to go through the Flashing Don't Walk sequence and then show Don't Walk before you have conflicting movements. Even with small intersections crossing two lanes, this is normally taking 10 seconds or more. For a car traveling 25mph, that's 366 feet or more away - longer than a block in many downtown areas.

You generally don't see traffic signals rest in a 4-way walk because it imposes long delays on vehicles. Rest in walk for the main street, where you can also serve the majority of vehicular traffic, or if you really want rest in all-red, all-Don't Walk so the signal is ready to go for whatever vehicle or pedestrian triggers it first.

Where I live, pedestrian signals have to flash green atleast 3 times before turning red. I don't understand why the US requires it to flash for 10 seconds, even if the street is narrow and it takes 5 seconds to cross.

The US is very accommodating to ADA considerations - way more than many other countries.

[roadfro]

The US standard for flashing don't walk time is a function of the crossing distance and an assumed pedestrian walking speed of 3.5 ft/sec. It was formerly 4 ft/sec prior to 2009 MUTCD (and this value can still be used if the controller set up to use the slower time when the pedestrian button is pressed for an extended period), but the slower time was adopted to accommodate an increasingly older population.

So a 60 ft wide street would have a FDW time of (60 ft) ÷ (3.5 ft/sec) ≈ (17.4 sec). This would likely be rounded to 17.5 or 18.

Bear in mind, too, that the MUTCD requires that the FDW terminates no later than the start of the yellow light. That means you also need a couple seconds for the yellow light in addition to whatever is required for the FDW before conflicting traffic can get a green.

Actually, MUTCD allows the FDW to extend into the red clearance (there's a couple different ways it can be set up). But most agencies use the method where FDW terminates no later than onset of yellow because it gives the most buffer between pedestrian phase and the conflicting vehicle phase.

[Mr Kite]

But can steady Don't Walk count towards the clearance period? I mean, if the FDW is 10 seconds at a site where it extends into the red clearance, can it be only 7 seconds at a similar site where FDW terminates on amber?

[jakeroot]

The US standard for flashing don't walk time is a function of the crossing distance and an assumed pedestrian walking speed of 3.5 ft/sec. It was formerly 4 ft/sec prior to 2009 MUTCD (and this value can still be used if the controller set up to use the slower time when the pedestrian button is pressed for an extended period), but the slower time was adopted to accommodate an increasingly older population.

So a 60 ft wide street would have a FDW time of (60 ft) ÷ (3.5 ft/sec) ≈ (17.4 sec). This would likely be rounded to 17.5 or 18.

Bear in mind, too, that the MUTCD requires that the FDW terminates no later than the start of the yellow light. That means you also need a couple seconds for the yellow light in addition to whatever is required for the FDW before conflicting traffic can get a green.

Actually, MUTCD allows the FDW to extend into the red clearance (there's a couple different ways it can be set up). But most agencies use the method where FDW terminates no later than onset of yellow because it gives the most buffer between pedestrian phase and the conflicting vehicle phase.

I spotted this at an intersection near me not that long ago. Very rare, but indeed permitted:

https://youtu.be/MXXuUl3WfQM

[Bitmapped]

The US standard for flashing don't walk time is a function of the crossing distance and an assumed pedestrian walking speed of 3.5 ft/sec. It was formerly 4 ft/sec prior to 2009 MUTCD (and this value can still be used if the controller set up to use the slower time when the pedestrian button is pressed for an extended period), but the slower time was adopted to accommodate an increasingly older population.

So a 60 ft wide street would have a FDW time of (60 ft) ÷ (3.5 ft/sec) ≈ (17.4 sec). This would likely be rounded to 17.5 or 18.

Bear in mind, too, that the MUTCD requires that the FDW terminates no later than the start of the yellow light. That means you also need a couple seconds for the yellow light in addition to whatever is required for the FDW before conflicting traffic can get a green.

Actually, MUTCD allows the FDW to extend into the red clearance (there's a couple different ways it can be set up). But most agencies use the method where FDW terminates no later than onset of yellow because it gives the most buffer between pedestrian phase and the conflicting vehicle phase.

I spotted this at an intersection near me not that long ago. Very rare, but indeed permitted:

https://youtu.be/MXXuUl3WfQM

What's shown in the YouTube video is not MUTCD compliant. The standard in Section 4E.06 Paragraph 04 of the MUTCD says that a steady Don't Walk signal shall be displayed for at least 3 seconds prior to the release of any conflicting vehicular movement. I'm guessing this is an older install, but the 2009 MUTCD also says in Section 4E.07 this should be a countdown signal since the FDW is more than 7 seconds long.

The FHWA guidance document I was looking at earlier said that if you had a countdown signal it had to terminate by the start of the yellow, but the option in Paragraph 05 and Figure 4E-2 in the MUTCD indicate that FDW can overlap the yellow as long as there is still the 3-second steady Don't Walk. So, either you'd need a long yellow light or an all-red clearance interval to make this work. Either way, we're still talking about extra time beyond the FDW before conflicting traffic.

FWIW, the coming version of the MUTCD reduces the 3-second steady Don't Walk requirement before conflicting vehicular movements to 2 seconds in Section 4I.06.

[jeffandnicole]

I spotted this at an intersection near me not that long ago. Very rare, but indeed permitted:

https://youtu.be/MXXuUl3WfQM

If we've learned anything from these forums: Just because it exists doesn't mean it's permitted.

[vdeane]

So, either you'd need a long yellow light or an all-red clearance interval to make this work.

How common is it to not have an all-red clearance interval?  I encountered such a light during my internship, and it struck me as both unusual and unsafe.

[BuildTheRussian]

Here in Russia, all-red intervals are not required. At the nearest traffic light intersection to me, traffic lights turn green as soon as the previous one has turned red. There are no crashes or close calls caused by that. Down the road there's an intersection where there is an all-red interval though, probably because it's a lot more busier.