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0 pointscpitman6y ago0 comments

FWIW, self driving trains are a very different problem. With self driving cars, the approach has been to use sensors on the vehicle and make autonomous decisions based on that input. This will never work for trains, because their stopping distances are so long that they cannot use a sensor to detect most oncoming issues.

Self driving trains will require more coordination, with central dispatch to tell them when/where to go. That leaves the intelligence on the train much more basic.

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4 comments · 2 top-level

qroshan6y ago· 2 in thread

Except you can always install sensors that can look as far as you want

cpitmanOP6y ago

Do you mean on the tracks?

There are hard limitations on sensing onboard the train. Tracks that bend around hills, etc. I have some exposure to wireless communication for trains, and one of the limitations is that you can often not get a line of site even from one end of the train to another.

dredmorbius6y ago

Not OP, but yes, along the right of way.

Since railroad tracks rarely get up and go walkabout, you can instrument them (conduction, video, lidar/radar) to the limits of your preferences and/or budget. Information can be relayed to both central control and individual trainsets.

iso9476y ago

So how do drivers stop with long stopping distance?

They have signals to tell them “stop”, they have speed limits posted, they have route knowledge. All detectable by computers, even without changes. Fast trains have in cab signalling in any case.

They have no decision about where to go (signal box sets the points/switch track), they have no decision on when to go (signal goes green)

The only bit which may need human input is the “ok to depart” notification when all the doors are clear at a station.

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