Street-running rail!

[Matthew]

This sounds logical, but I do worry that in the period where it has just been implemented you would have a lot more accidents from people used to the old system.

In Zurich they randomized the phases before introducing TSP in order to get people accustomed to that

Getting people to think and be aware while driving is good for safety overall. That's the same principle which roundabouts employ quite successfully.

 

[bigeman312]

One thing you can do with signal priority is called "phase rotation" where you move phases around to avoid conflicts and excessive waiting. For example, if a left-turn signal usually goes green before the thru-phase, but a trolley needs to go thru, then you can "rotate" the left-turn phase to be after the thru-phase instead of before.

I'm pretty sure this is how Chestnut Hill Ave & Comm Ave is set up. I drive through this intersection all the time.

 

[novitiate]

In Zurich they randomized the phases before introducing TSP in order to get people accustomed to that

Getting people to think and be aware while driving is good for safety overall. That's the same principle which roundabouts employ quite successfully.

That's pretty clever... I have to admit, some sort of signal priority would definitely be the first major improvement I would want to make to the Green Line (stop consolidation on the B east of Packard's would be the second).

I'm not sure about the unsignalized U-turn, though- it seems like you would have to slow trolleys down in the area of the crossing no matter how careful drivers would be, which would undo some of the benefit of signal priority.

 

[Matthew]

You could have detectors which put up a yellow-then-red light for the U-turn whenever a trolley is near.