21–30 of 64 posts
Its striking how much less bunching there is on the two routes (P/G) that operate in exclusive right-of-way.
The worst bunching occurs downtown and right in front of the University of Pittsburgh.
And, Pitt is going to cause bunching at discrete times when classes end.
Naive question: when buses are bunching, can't the front bus skip stops that are not needed for dropoffs? (the driver would have to announce that passengers need to request their stops of course).
> how do we make this better? Just teach the bus drivers to let the empty busses overtake the crowded one. It won't solve the pauses when there will be no bus coming, but at least it increases the passenger comfort by a good margin and the average speed by which the bunch travels increases too.
> Pittsburgh, however, as an unusual misfeature in that the single bus lane goes the wrong way against one way traffic (3 lanes of cars going one way--1 lane of bus going the opposite) for a non-trivial amount of length flagged as "hotspots".
> how do we make this better? Just teach the bus drivers to let the empty busses overtake the crowded one. It won't solve the pauses when there will be no bus coming, but at least it increases the passenger comfort by a good margin and the average speed by which the bunch travels increases too.
Naive question: when buses are bunching, can't the front bus skip stops that are not needed for dropoffs? (the driver would have to announce that passengers need to request their stops of course).
Ah this is an interesting idea. Passengers already have to request when they want to get off. I'm assuming you mean if no one wants to get off, a bunched up bus skips a stop because a bus behind it says "I'm behind you, I'll take this stop." That would mostly work, but the problem in Pittsburgh at least is the bus bunching happens between related but not quite identical routes. For example, the 61A, 61B, 61C, and 61D…
As is hinted at by the paper, bunching is generally caused by factors such as traffic which makes it hard to actually eliminate. Transit agencies have tried various solutions to the problem and it is very much a work in progress. One thing I have noticed is that transit agencies tend to have sub-optimal data for their service so they tend to be slow at fixing scheduling related issues.
Earlier quoted context omitted.
Ah this is an interesting idea. Passengers already have to request when they want to get off. I'm assuming you mean if no one wants to get off, a bunched up bus skips a stop because a bus behind it says "I'm behind you, I'll take this stop." That would mostly work, but the problem in Pittsburgh at least is the bus bunching happens between related but not quite identical routes. For example, the 61A, 61B, 61C, and 61D…
Technically it isn’t bunching if it is for different routes. The standard industry definition for bunching as I understand it is when multiple buses for the same route are bunched up. As is hinted at by the paper, bunching is generally caused by factors such as traffic which makes it hard to actually eliminate. Transit agencies have tried various solutions to the problem and it is very much a work in progress. One th…
> how do we make this better? Just teach the bus drivers to let the empty busses overtake the crowded one. It won't solve the pauses when there will be no bus coming, but at least it increases the passenger comfort by a good margin and the average speed by which the bunch travels increases too.
I suspect this isn’t as easy as you think. Where I am (Seattle) an empty bus overtaking a full one isn’t really feasible given traffic and lane size considerations.
I mean, where I live, busses manage to overtake in a one lane for each direction scenario (which is theoretically complicated, but works out in practice as traffics lights can give you chances to use the opposite lane). Nevertheless, what is important is that the front bus waits until the busses behind him have taken the lead. Otherwise there will be very few opportunities to safely overtake the front bus.
> how do we make this better? Just teach the bus drivers to let the empty busses overtake the crowded one. It won't solve the pauses when there will be no bus coming, but at least it increases the passenger comfort by a good margin and the average speed by which the bunch travels increases too.
As I commented elsewhere, passing is not always an option in Pittsburgh. > Pittsburgh, however, as an unusual misfeature in that the single bus lane goes the wrong way against one way traffic (3 lanes of cars going one way--1 lane of bus going the opposite) for a non-trivial amount of length flagged as "hotspots".
But yes, that going against the flow doesn't make overtakings any easier.
Love this. I’ve experienced bus bunching in several cities at this point (LA, DC, and now Seattle). It seems to be a known failure mode of metro transit planning. First step is understanding what your problem space looks like. Curious to know what anyone here thinks could be a solution. I doubt skipping stops is one. I suspect that speed controls are probably the way to go. Edit: kudos to doing this in R. I’ve done o…
Pittsburgh is a super interesting city from a transportation logistics and efficiency perspective. It's got an extremely difficult topography mixed with a rather obstinate electorate that has routinely de-prioritized mass transit. This particular piece emphasizes what anyone who attended CMU could tell you - if you're going to take the 62C anytime during rush hour, you better learn to hold your breath.
61C, and it will come sooner or later at rush hour, but there's no point in looking at the schedule.