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Train doors require GPS signal to open despite stations being underground (2014)

ciras.org.uk

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Re: Train doors require GPS signal to open despite stations being underground (2014)

#21

Post by hobs »

Why wouldnt this using something like radio waves in each station from a few sources, wouldnt it be super easy to tell your position fairly accurately with just a few radio sources? I did some googling and indoor localization systems can determine your location down to 3cm, I think that would be way more accurate than the 50m or so I have observed of GPS units while they moves around.

And obviously they would be 10000x louder than the gps signal, so you couldnt lose it unless someone was purposefully interfering with the signal.

Re: Train doors require GPS signal to open despite stations being underground (2014)

#22

Post by sklogic »

marbletiles wrote: post #5

> Operation of Class 377 train doors require a (GPS) signal to identify that the train is in a station to allow the Driver to open the doors. Effectively this prevents the doors being operated in error when the train is not at a station and as such is a safety feature of the trains. Was there some epidemic of doors being opened outside stations that I missed? This smacks of a solution looking for a problem

Guess they want to make sure that cattle won't ever escape again as they did here: http://www.bbc.co.uk/news/uk-england-cambridgeshire-11658110

Re: Train doors require GPS signal to open despite stations being underground (2014)

#23

Post by cesarb »

hobs wrote: post #21

Why wouldnt this using something like radio waves in each station from a few sources, wouldnt it be super easy to tell your position fairly accurately with just a few radio sources? I did some googling and indoor localization systems can determine your location down to 3cm, I think that would be way more accurate than the 50m or so I have observed of GPS units while they moves around. And obviously they would be 1000…

Or with a balise (https://en.wikipedia.org/wiki/Balise).

Re: Train doors require GPS signal to open despite stations being underground (2014)

#24

Post by davidmturner »

This was the reason I was given at London Victoria Station for the doors taking a long time to open. Oh for the days when the doors weren't controlled by a computer, and passengers could open the windows -- always a joy when the air conditioning fails.

Re: Train doors require GPS signal to open despite stations being underground (2014)

#25

Post by davidmturner »

This was the reason I was given at London Victoria Station for the doors taking a long time to open. Oh for the days when the doors weren't controlled by a computer, and passengers could open the windows -- always a joy when the air conditioning fails.

Re: Train doors require GPS signal to open despite stations being underground (2014)

#26

Post by marbletiles »

marbletiles wrote: post #5

> Operation of Class 377 train doors require a (GPS) signal to identify that the train is in a station to allow the Driver to open the doors. Effectively this prevents the doors being operated in error when the train is not at a station and as such is a safety feature of the trains. Was there some epidemic of doors being opened outside stations that I missed? This smacks of a solution looking for a problem

Thinking about this some more, I still don't understand. If the goal was door safety, why not use the same release systems automatic trains (eg underground) have?

Re: Train doors require GPS signal to open despite stations being underground (2014)

#28

Post by jimktrains2 »

I find it difficult to believe this was all deployed without manual overrides. What about in the case of an emergency?

Also, isn't the first objection to GPS anything usually "it doesn't work well in buildings or around buildings"?

Re: Train doors require GPS signal to open despite stations being underground (2014)

#29

Post by vinceguidry »

themartorana wrote: post #2

"...and the trains have needed to be rebooted." Nope. No thanks. Do not need my trains to be so "smart" that the only way to get them working properly is CTL-ALT-DELETE. Seriously.

Gives a new meaning to the term, "crash-only software".
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