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Sounds similar to Traffic Priority Signalling, is that what you're referring to? Or is this something completely separate?

Well, I guess it depends on how you define priority signalling.

There are a lot of really good modern systems that are predictive and can account for vehicle speed, and adjust the light timing. This can't really do that. It just enables an alternate cycle when a streetcar is detected - and in some cases, the streetcar will be forced to wait for its turn.

Dan
 
Well, I guess it depends on how you define priority signalling.

There are a lot of really good modern systems that are predictive and can account for vehicle speed, and adjust the light timing. This can't really do that. It just enables an alternate cycle when a streetcar is detected - and in some cases, the streetcar will be forced to wait for its turn.

I don't have a very deep knowledge of the technology, but in simple terms, I would be happy if before turning yellow, the traffic circuitry asked "Is there an approaching LRV within x meters of the intersection?" and then hold off on a yellow light until the LRV has cleared.

That won't help LRV's that approach after the yellow/red cycle begins. These would still encounter delays, but they would most probably only have to sit for part of the cycle. Any time that a car squeaks through on a delayed yellow is a delay eliminated. That has to help.

A more sophisticated approach might let those late-arriving cars tell the circuitry "hey I'm coming, please start the yellow for the cross traffic so that my signal is green by the time I get there" - but I wonder if spacing allows that. The earliest that an "I'm coming" trigger is meaningful is when the LRV leaves the previous stop. I wouldn't trust signalling to predict the dwell time at the stop, as if it underestimated the dwell time, lights would be cleared for too long (holding up cross traffic autos) until the LRV actually arrives. That could play havoc with auto traffic. Any light close to the stop might not be able to cycle quickly enough to clear before the LRV arrived, so again some delay will have to happen.

Or we could apply a KISS formula - hire an army of kids to play street hockey and just shout "Car !" whenever an LRV is approaching, and let the signals work from that cue. :)

- Paul

PS - I'm quite vehement that the line needs all the traffic priority that can be applied. I'm just observing that even a good system won't be "perfect".
 
If they could time the signals for a green wave (synchronized signals), it will help a lot without any transit priority than employing all sorts of advanced techs on badly synced signals.

We all know how stupid it is for everyone to wait a minute for a major intersection just to have to watch the next minor street signal turn red cause someone wants to cross the road. That guy was waiting at the same time everyone else was stuck behind the previous signal.
 
I don't have a very deep knowledge of the technology, but in simple terms, I would be happy if before turning yellow, the traffic circuitry asked "Is there an approaching LRV within x meters of the intersection?" and then hold off on a yellow light until the LRV has cleared.

That won't help LRV's that approach after the yellow/red cycle begins. These would still encounter delays, but they would most probably only have to sit for part of the cycle. Any time that a car squeaks through on a delayed yellow is a delay eliminated. That has to help.

The same system is applied to other streets downtown - Queen, and formerly King are two that I recall, and the other streetcar routes I'm less certain of - to hold a green light if a car is sitting at a stop at that particular intersection.

But can it do both? No. Because of how the system is triggered, it is either or.

A more sophisticated approach might let those late-arriving cars tell the circuitry "hey I'm coming, please start the yellow for the cross traffic so that my signal is green by the time I get there" - but I wonder if spacing allows that. The earliest that an "I'm coming" trigger is meaningful is when the LRV leaves the previous stop. I wouldn't trust signalling to predict the dwell time at the stop, as if it underestimated the dwell time, lights would be cleared for too long (holding up cross traffic autos) until the LRV actually arrives. That could play havoc with auto traffic. Any light close to the stop might not be able to cycle quickly enough to clear before the LRV arrived, so again some delay will have to happen.

These systems exist. But the Transportation Department seems to be vehemently against them. Their mantra is that they are there to move cars, and damn anything else that gets in their way. The TTC needs to fight any time they try and add any sort of system that would benefit them - or even a set of signals to help them exit a station loop.

Dan
 
The way the signal priority works on King right now is quite good - if that type of priority was available on Eglinton, I think it would be fine. Not 100% priority, but certainly significant.

The "trick" is to do adjustments more frequently, especially with changing circumstances. If they only do adjustments to timing once a year, you only get conditions at that one time available. Not just weekly or daily, but sometimes even hourly or they can change by the minute.
 
Screen Shot 2020-07-30 at 10.00.20 AM.png

Did anyone catch it?
 
As many of you may know, a noose was found at a Crosstown construction site in the last few days.

Apparently the culprit has been identified. The union demanded and received his resignation, he has now been banned from all Metrolinx construction projects. The name is also in the hands of police.

 

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