07-18-2017, 01:07 PM
(07-18-2017, 12:38 PM)Viewfromthe42 Wrote: I *think* it's the idea of only having to change the lights for maybe 5-10 seconds of flow to empty all queued cars if no pedestrians are allowed to block cars using the intersection, versus at least 15-20+ seconds required just to let pedestrians cross, and maybe more to allow advance green/post-pedestrian clearing of cars. Not that I agree with that, I just think that this is the reasoning.
This is absolutely correct, it derives from the fact that transit planners make virtually all their decisions based on the premise the goal is to optimize vehicular throughput.
This makes a small amount of sense on roads like Fischer-Hallman, and minor side streets. But at Willis Way and King, utterly illogical. This frustrates me to no end, and that one has been like that for years. Although, the one at West and Victoria pisses me off more, as I live there and routinely miss the light.
Of course, the fact is, our signal polices are extra stupid. Yes, turning on the ped light does take longer, but there is no need for it to take 20+ seconds. The Victoria and West intersection when crossing Victoria, for instance has only about 7 seconds of flashing, but 10+ seconds of walk. You might think, that's great, but it really isn't. What are the chances a ped will arrive in that 10 seconds? It would be better for 2 seconds of walk (just long enough to notice and set off), and 7 seconds of flashing for crossing, combined with a lower delay (wait time). Right now, if you miss a light, you wait through a minimum 45 second walk sign in the other direction, plus a 15 second flashing phase. Would be much better for pedestrians to cycle the light more frequently, but again, worse (or maybe equal if you trade off less walk time) for cars.
Even worse, most lights are programmed to stay on as long as there are cars coming from the other direction (within some limits) so the detectors under the road tell the lights that cars continue to come, yet somehow, that same light won't give extra time to the pedestrian who presses the button, even if there is enough time for walk and flashing phases within the normal limits for that intersection. As a result, a pedestrian may wait at a green light for an entire light cycle, instead of the truncated one, just because there are more cars.
I can rant all day about our signal systems. Trust me.