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Wait ages for a bus and then two come along at once

jasmcole.com

41–47 of 47 posts

Re: Wait ages for a bus and then two come along at once

#41

Earlier quoted context omitted.

There's a ramp inside the train that needs to be deployed to bridge the gap to the ramp at the platform.

Sounds like a strange design to me. On most of the train-based public transit I've seen (and even some of the "rapid" buses), the floor of the car is aligned with the floor of the boarding area, such that ramps are unnecessary.

they're aligned, but there's a small gap that needs to be bridged.

Re: Wait ages for a bus and then two come along at once

#42
Great article. And here's some academic research that models the dynamics of bus bunching and proposes a decentralized control scheme to minimize a combination of passenger wait time and travel time:

http://www.its.berkeley.edu/publications/UCB/2011/VWP/UCB-IT...

...And here's a product we created to commercialize this research:

https://www.youtube.com/watch?v=YQXZybHO52A

Full disclosure: I am a co-founder along with the authors of the above paper of Via Analytics:

v-a.io

Re: Wait ages for a bus and then two come along at once

#43
post #8

Bunching happens a lot when one delay causes one bus/streetcar/train to hold up all the ones behind it. Best solution is letting transit vehicles going the opposite direction to turn ahead ahead of the bottleneck and serve the passengers waiting at the stations in front of the delay area.

Another solution would be to have the lead bus skip pickup at a stop (or two). You'd need clear and solid signage to assuage people waiting though. Something like "Behind schedule, dropoff only. Next bus arrives in 2 minutes".

Or set a dropoff only stop 50 yards from the designated stop. That way the people from the stop don't try to board.

Re: Wait ages for a bus and then two come along at once

#44

Earlier quoted context omitted.

My dad always causes a ~90 second delay for the Denver light rail, because the operator has to activate the wheelchair ramp for him. How do they handle that sort of thing in Tokyo? (Also, I often see multiple light-rail trains bunched up after sporting events.)

Perhaps they just speed the train up to bridge the time gap. That seems like the simplest solution. Do light rails run on a set speed?

That's sort of the elephant in the room, as far as I'm concerned: you don't construct schedules assuming the best possible circumstances and maximum speed.

At least for light rail, it's quite normal to have trains stop for a good few minutes in certain stations. If there are delays, I'm sure that time gets cut.

Re: Wait ages for a bus and then two come along at once

#45
post #32

Earlier quoted context omitted.

So, pay as you board.

Not in a way that delays you - the driver doesn't count change or anything.

Almost nobody in Chicago uses cash to board, but if there are 20-30 people boarding a bus, it can still take over a minute as they all have to go through the front door and tap their cards (and of course, it doesn't always work the first time for some reason).

Re: Wait ages for a bus and then two come along at once

#46

Earlier quoted context omitted.

The first thing I'd want to know, to see whether this is true, is "when two buses clump, do they both arrive between the scheduled arrival time for bus 1 and bus 2, or do they both arrive on time for bus 2?" The only time I've personally experienced bus clumping, they were both late (for the bus 2 time). That doesn't suggest that bus 2 was being sped up relative to expectation.

If buses don't generally pass each other (for reasons of both practicality of doing so the way stops are laid out, safety and policy), bus 2 making their schedule is dependent on bus 1. So if bus 2 is late, it can be bus 1's fault.

But they do pass each other. Look at quarterto's comment:

> I've noticed that in the "two come along at once" scenario, the second bus often leapfrogs the first, skipping a stop while the first bus picks up passengers.

Re: Wait ages for a bus and then two come along at once

#47

Earlier quoted context omitted.

If buses don't generally pass each other (for reasons of both practicality of doing so the way stops are laid out, safety and policy), bus 2 making their schedule is dependent on bus 1. So if bus 2 is late, it can be bus 1's fault.

But they do pass each other. Look at quarterto's comment: > I've noticed that in the "two come along at once" scenario, the second bus often leapfrogs the first, skipping a stop while the first bus picks up passengers.

That may be true in some cities, and not true in others. As a car driver in a big city, I've rarely seen a bus pass another bus, but I have seen buses all bunched together. I suspect there is no incentive for a bus driver to pass another bus. He's not the one in a rush to get anywhere.
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