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Many bus routes have a 5-10ish min break at some point (usually the main station) in the route. If you can utilize those ten minutes to do a top-up, you can go a lot further on the same sized battery.



No bus route should be more than 15 minutes between full and empty. That is you start at some station, go 15 minutes, then turn around and go back. There are many systems that attempt to do more, but there is no point: people have places to be: on the bus is not on that list. That 15 minutes means an average of 7 minutes, now they walk to some other express bus that gets them nonstop (at faster speeds) to someplace, but you still only get 15 minutes to get there before it isn't worth the bother, than 7 more minutes on some other bus. Add in 5 more minutes of walking time (and transfer time!) and we are at 45 minutes - this is unreasonably long for normal trips already, but it is the best you can do!.

In short there are plenty of places to switch buses if you need to.


There are two critical aspects to the bus routing problem. One is that no matter how well you design your system, there is always variance in the arrival times of a bus at any given stop. If you expect people to switch buses, then you need to account for this variance, and this means adding buffers. Nothing makes people stop using buses faster than missing your connection because your bus was late.

The other aspect is the what city topology you are dealing with. In square grid cities, you can probably put a tram on every road, and with one switch over, get to where ever you need to get to.

But many organically grown cities end up using the hub-and-spoke model, where there are main stations where many different buses meet. People switch over to the next connection (and you need a buffer here). Critically, you need all the buses to meet at roughly the same clock time, say every 30 min. Now, one thing you realize immediately is that not all routes are equal. One route might be only 25 min, Either you make it longer and waste fuel, and time for everyone sitting on the bus, or you wait an extra 5 min at the main station.

Bus scheduling is very difficult problem in real cities with weird topologies and real traffic issues. Buffers are a necessary part of any reasonable solution.


I'm coming from a different perspective: regardless of all else (all those issues you raised are very real), people need to get where they are going in a reasonable amount of time. Most bus service fails to account for that, but if you can't get people there in a reasonable amount of time there is no point in trying.


I agree that a system that does not deliver is going to fail. Transit systems can have improved scheduling in two ways:

(1) Better scheduling system. My opinion is that most real world systems are not too far away from the optimal trade-off curves. There is always room for improvements, or choosing better trade-offs, but it will rarely drastically improve things.

(2) More ridership: Most problems with speed just disappear if more people ride. For example, you do need a solid buffer when buses come every 30 min or more. But buses that come every 10 min or less, you can get rid of all buffer. A lot of scheduling problems are just not-enough-users problem.


No transit system has the money needed to provide great transit to their entire city even though if they did it would save all residents a large pile of money. They compromise on only the densist areas which are easy but mean that you can't get anywhere else reasonably. Of course some areas will always be easier than others to get to, but far too much of any city is not reasonably reachable without a car and that is a problem.


Am I misunderstanding you about the 15 minutes interval?

Every workday I take a one-seat King County Metro bus ride that lasts about 1 hr. The bus starts at a layover facility and ends at a different layover facility.

I don’t see how this 15 minute interval maps to my actual commute?


I don't think you're misunderstanding. I think the person you're responding to is misunderstanding that we were referring to trip end points (layover locations).


Very few people will accept commutes that long and so they are not something to optimize for.


Is there any bus route anywhere that never goes more than 15 minutes from the depot?


Not that I know of - but there shouldn't be.


How do you get somewhere which is 20 minutes from the depot, or in general between any two points that are more than 15 minutes apart?


You put in a different depot for the 20 minute trip. With express buses the trip between the two depots may only be 5 minutes.

People through history have always considered about half an hour a reasonable daily commute. Doesn't matter if it is a hunter-gatherer going to their gathering grounds (if they follow herds they will move camp if the herd moves more than half an hour), or "modern man" going to the office, half an hour is what you get. Everything I said is based on making as many of those half hour trips possible as I can - but not all trips can be done that way and some locations will be left out.


You would then be subjecting people to indirect paths with multiple transfers. Instead of going from A to B you'd have to go from A to the first bus depot to the second bus depot to B, waiting for another bus at each transfer. If the trip was 30 minutes to begin with, now you've made it 45 (at best).


True for that trip. However in return I've made a large number of other trips possible that couldn't have been done.


Have you though? You're at A, near but not at the first bus depot. If there is a bus that originates at the depot, stops at A and then takes you all the way to B, you get there in 30 minutes. If it only takes you half way to B, you have to go half way, wait there for another bus from a different depot, take it back to that depot and wait for a third bus from the depot to B.

Not only is that slower, having the first bus stop there and turn around instead of going all the way to B hasn't benefited anyone else either. The route from the first depot to the halfway point is still being covered by the same bus route. The interval is determined by how many buses cover that route and not just by its total length, and another bus that covers that section of the route might even go somewhere other than B after reaching the point you'd have had it turn around to go back, also giving a faster option than multiple transfers for people who want to go from A to C. When A, B and C are all high density areas, creating direct routes between them makes sense even if they're each more than 15 minutes apart.


Sorry, but, what the hell? This is Hacker News at its finest: completely talking out of its ass.

This isn’t how bus routes work, and this isn’t how people ride busses, on most if not all of the…many PT systems I’ve used in multiple states / countries.


There is a reason people complain about buses and prefer to drive in so many cases. Operators try to compromise on cheap and end up with service for those who after 5 DWIs can't get their friends to drive them anymore.


Forcing more people to change busses more often for their routes just to fit some 15 minute max route ideal is going to make more people hate the busses.


Making a lot more destinatians available will make people use the bus.


You're not necessarily making more destinations available. You're potentially just requiring more changes to go to the same destinations.

Imagine a metro area with somewhat grid-like streets (or at least common paths) that go on for an hour+ in each direction. People still generally cluster to 20-30min from the destinations they care to go to, so it doesn't break that standard. Breaking it up into four 15-minute stretches isn't making it better for anyone. All you're doing is forcing people to get off one bus at an edge and hop on another. Just run more busses on the full path so there's still ample service for the changes.

How does forcing the 15-minute max path make more destinations available?


Your system makes destinations on only one line easy. Mine brings in many more lines.


It doesn't inherently make more lines. You might (you probably will) just have the same lines more broken up.

You could also just have more lines even if they're long. The length of the lines doesn't change the number of them. It's just a question of how many busses and drivers do you really have and what service interval are you trying to hit.

If you're arguing they should have like a 15 minute hub and spoke model, you might also be forcing some really inefficient routes and once again force people to change busses more when one bus route could have better served the community.


This is highly regional - any major city with a decent transit system will have excellent bus routes in dense areas. Also, “operators” usually means bus drivers, not transit agencies


Only dense areas. Some cities are ignoring dense areas that other cities have proven can support great service because they are not the densest there. People have places to be, and large parts of any city do not have reasonable transit options even though the density is there. Too often you are foced to take the long trip downtown and then back out even though your destination is just barely beyond walking distance.




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