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Comment by masklinn | Hacker News Reader

I have to say I'm a bit weirded out by there being a conductor (according to the demo videos) on a brand new subway project. Do the platform door prefigure automation in the future?

Good thing on the large diameter though, IME many of the tube's older sub-surface lines are unfortunately (and uncomfortably for modern average heights) small.

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A commenter further down said that these trains are supposed to also run on the normal train lines. This probably means that they have to comply with the regular train regulation, which are quite different from the subway regulations and make automatic driving a lot more difficult.

Yeah. London won't allow fully automated trains without platform edge doors, and it would be impractical to put them on the Great Eastern Main Line or the Great Western Main Line with the variety of other trains that share those tracks. AIUI Crossrail is planned to use fully automated signalling eventually (i.e. similar to the Victoria Line, where the driver only pushes the button at each station and speed is automatically controlled between stations) once ETCS in Britain is standardized enough.

Strange because the DLR is almost completely automated (no driver, but ticket inspector closes the doors) and has no platform edge doors. But they do have emergency stop buttons on the platforms.

AFAIK It's the lack of a human making the close doors / start moving decision that leads to a need for platform doors.

(The Central, Jubilee, Northern and Victoria lines also use automatic operation to similar levels as the DLR, it's just less obvious as the train operator still has a separate cab).

> AFAIK It's the lack of a human making the close doors / start moving decision that leads to need for platform doors.

There is no such need. Lyon's line D has been running fully automatic since 1992 without platform doors[0], the only major accident has been a drunk falling on the train having jumped from a mezzanine.

[0] https://www.youtube.com/watch?v=ubdJ35NBrbE

Same in Copenhagen[0], but they do appear to have LIDAR units monitoring the track edge at stations without doors.

[0] https://youtu.be/R8QvM000uyE?t=151

Copenhagen has since fitted platform edge doors to all stations, above and below ground.

Of course there is no such technical _need_, most kinds of these needs are driven by _legal_ requirements founded in fear of full automation. Fully automated systems were realized before your example already in Vancouver's SkyTrain (1986) and even BART was supposed to be specified to be fully automatic.

Small correction - they can also be driven manually, a flip up panel on the front seat allows the conductor to take control in the case of a complete (or widespread) signalling failure. They're restricted to 12mph though as there are no signals at all and everything must be done by sight.

    > allows the conductor to take control in the case of a
    > complete (or widespread) signalling failure

Or, having ridden that line as part of a regular commute, whenever the conductor gets bored.

I don't think they actually get to drive the train then, just get the press the close door button on the panel. The train still drives to the next station without any human input.

Most automatic trains can't be driven by humans under normal circumstances because signaling information is fed to the train far faster than any human could react to it.

For something like a train I would think you'd want one or more humans babysitting it all the time no matter how automated it is. Thousands of people would ride it every day, all the time, even if it is 100% automated what would be the point in cutting that particular corner? Saving labor costs on conductors are probably not worth it for insurance reasons alone, even if the conductor sits around twiddling his thumbs all day long.

If the conductor sits around twiddling his thumbs all day long, what is the point of him existing in the first place? For a fully automated train system, what useful function does the conductor serve?

As i understand it, there's a rule that requires a member of staff on any train that's properly underground. Ostensibly for safety in emergencies, but possibly because the unions fancied the jobs.

On current tube and big railway trains, that member of staff is the driver. On the DLR, it's the train captain. On an automated Crossrail train, it could be a guard (it's buses that have conductors!).

I don't know, but this could have as much to do with TfL politics as technology.

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