> This doesn't work for an electric aircraft, or many normal public transport methods as they are all focused on batching people up into large groups (planes, trains, etc).
True, but as the batch size gets smaller, so does the interval between vehicles. "one every minute, on the minute" is not much different from "It leaves when you arrive". This may not work for aircraft, but it certainly would for automated light rail systems.
> Subways solve this problem by running every couple of minutes.
Similarly, in many transport corridors intercity rail runs several times an hour (not so much in the US) and shuttle flights run every hour or two. Which are also sufficient in those contexts, in that it becomes reasonable to show up at the station/airport without checking the timetable.
Also consider this is bus-tier people moving, not even train. You just have small individual units moving along one track. With even passenger rail, you have to have set departure times measured in at least 10 minute blocks, something like this could have a departing train every 5 minutes and you could go through a turnstable the same way you get on a subway.
What? In my country every single station has a timetable saying which metro/train/bus stops there at exactly which minute. Are you suggesting we should randomize public transport schedules?
It is "only a minute of your life" start to become critical when the next train leave one hour later. It does improve throughput a lot in public transportation situations, not so much in shopping malls.
Faster trains can support more trips per day on the same track. Now, the problem is that people generally want to leave at the same time, but if the journey time was say 15 minutes, you could do 5 minute frequency during peak with a few trains.
There would have to be few stops...even point to point, for this to work though. Think Shinkansen.
I can't remember where I read it but someone stated something similar about train scheduling (I'm paraphrasing here); When the train departs every 15 minutes getting the train becomes a non issue, when the train departs once an hour it becomes an ordeal.
> In reality there is a train e.g. every hour or so, or even none at the same day
That really depends on your route. Some busy lines in the UK have trains every 30 minutes, 15 minutes or even 10 minutes. Across London, it might be every 5 minutes or even every 2.
Put another way: if you assume 16-passenger shuttles, you have to have 26 second headways between cars in order to meet capacity.
If you don't split the track to allow unloading, you have 26 seconds to disembark 16 passengers, embark 16 more passengers, and then clear the platform in enough time to allow sufficient safety margin for the car immediately behind you. Station dwell times (essentially the time from train is fully stopped to time it starts accelerating, and therefore not including the last bit) are upwards of 30 seconds and much likelier to be close to a minute, which can't be done in sufficient time. Especially because full capacity cars generally require more time at stations, and I have to imagine that modified Teslas that can fit 16 people aren't going to be quick to navigate.
If you have multiple platforms at each station to accomodate the long station dwell time, maybe it could be done, but I suspect that it'd blow out their construction budget because of the extra space needed.
Does this ever actually happen though? I'm not aware of variable length passenger trains along a single route. And the stations for boarding are only so long.
> As a commuter knowing you only have to wait a max (n)minutes as opposed to max 2(n) can be the difference between deciding to take a train or using some other means of transport
Agreed. In my mind, the most important step to make is to increase frequency to the point where passengers think of trains in terms of frequency of arrivals, not by a specific timetable.
At longer wait times, you plan around getting to the station early, hoping the train isn't late, hoping it's not too overcrowded, etc., each of which is a mental barrier to taking the train.
At shorter wait times, all of these concerns disappear because "oh well, there's another one in 3 minutes".
> random factor of passenger loading and unloading and changing gaps between trains as they accelerate and decelerate between stations.
Solution: Never arrive early, never depart late, and keep the stopping durations fixed, at the longest time possible (which is one quarter the time between the two closest neighbouring stations).
But you're always limited by loading time. If you take X seconds at each stop then you will end up with X * speed distance between each car. Even at 30s loading and 50 kph you're looking at 400 meters between each train.
I'm pretty sure the described tactics should succeed at optimising expected travel time, but they (knowingly) do so at the cost of variability.
I regular get to experience the opposite: waiting 20min in the rain, at which point three busses arrive as a group.
Yet another extreme is low variability with high scheduled travel time, achieved by including a minute of slack at every second stop or so.
It's a result of an inherent instability in bus operations: As soon as the intervals diverge only marginally, faster busses become even faster, because there are fewer people waiting for them and vice versa.
The solution with fade out / fade in is pretty clever. Short layovers will cross-fade automatically, but you don’t need complicated internal information about which train continues from one run to the next.
Stopping would be neat, but may also be visually messy.
Could make sense for short distance, low frequency. I know of a few services on branch lines that have long linger times at stations. They will do a 10 minute journey twice an hour and stay in the station between trips.
True, but as the batch size gets smaller, so does the interval between vehicles. "one every minute, on the minute" is not much different from "It leaves when you arrive". This may not work for aircraft, but it certainly would for automated light rail systems.
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