Train doors require GPS signal to open despite stations being underground (2014) • Hacker News Board

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

#11

Post by mikeash » Sat, Mar 14, 2015, 2:45 PM UTC

TillE wrote: post #9

The only advantage GPS would have is that you don't have to install something (eg, a powered RFID tag) in each station. And yet, they've had to install "GPS repeater beacons" to work around this problem. Sounds like a typical case of bad design.

Somebody decided that GPS was a good idea here, and didn't think about problems underground. Silly, but understandable.

Somebody else decided that having doors controlled by location was a good idea here, and didn't think somebody would specify a system that doesn't work at some stations.

At some point during procurement and installation of the equipment you'd think somebody would have raised a red flag. Unless, of course, they were simply told to install GPS equipment, and not why. Or they were told why but nobody listened to them when they explained why it wouldn't work right.

Sounds to me more like bad organization than bad design, although of course it's hard to tell from this distance.

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

#12

Post by sthreet » Sat, Mar 14, 2015, 2:51 PM UTC

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

The article wouldn't load for me, but did it say anything about why they don't just require the train to be stopped for the doors to open?

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

#13

Post by smcl » Sat, Mar 14, 2015, 2:52 PM UTC

blibble wrote: post #10

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

it's more common that the driver opens the doors on the wrong side, or at a short platform opens all the doors instead of, say the first 8

Oh god, opening doors on the wrong side would be absolutely terrible in rush hour - people back away from the door they think will open, and squeeze a few people out the other side onto the live wire, or perhaps into the path of a train arriving from the other direction.

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

#14

Post by [deleted] » Sat, Mar 14, 2015, 2:55 PM UTC

sthreet wrote: post #12

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

The article wouldn't load for me, but did it say anything about why they don't just require the train to be stopped for the doors to open?

[deleted]

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

#15

Post by crazychrome » Sat, Mar 14, 2015, 2:55 PM UTC

> ... and trains have needed to be rebooted.

Since when that default solution to any problem of any device embedded with CPU, is to reboot?

Welcome to the digital age!

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

#16

Post by ceeK » Sat, Mar 14, 2015, 2:57 PM UTC

I actually experienced this in St Pancras International last week!

The train stopped in the station, but the doors didn't open for a good 5 minutes. The driver issued a statement stating that there'd be a slight delay before the doors opened.

I recall thinking: what possible reason could there be for not opening the doors? Congestion? Electric failure?

Well, turns out it's the most ludicrous one.

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

#17

Post by sandworm » Sat, Mar 14, 2015, 3:01 PM UTC

So what happens in a power failure?

I can see the need and advantage of a system to make sure that only the appropriate doors open at certain stations, but surely this could have been done with information at the local level. Barcodes, NFC, RFID ... to go with sats hundreds of miles in the sky augmented by repeaters is overly complex.

Passengers are not cattle. I don't see why they cannot have local door control when the train is stopped for more than 5/10/15 minutes. The risk of death by idiot openign wrong door surely is less than the risk of death by fire/poison gas/axe murderer, all of which have happened on trains.

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

#18

Post by a3n » Sat, Mar 14, 2015, 3:05 PM UTC

FFS. A line in the station that the operator pulls up to, and two handles in the cab that have to be operated in sequence and simultaneously. And now the operator can open the doors whenever and wherever necessary, even while the train is rebooting.

Or were masses of people trapped in cars in the decades of operation prior to this, because the operator couldn't figure out where he was and wouldn't/couldn't open the doors?

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

#19

Post by cnvogel » Sat, Mar 14, 2015, 3:17 PM UTC

crazychrome wrote: post #15

> ... and trains have needed to be rebooted. Since when that default solution to any problem of any device embedded with CPU, is to reboot ? Welcome to the digital age!

Oh, probably you can avoid the reboot by changing the access level to "Service" (username: service, password: service123), choose "Disable all Safety Systems", click "OK" on the dialog popping up telling you that this is forbidden when operating on public rails and having passengers, and just continue driving.

[yes, completely made up, but corresponds to what's happening daily in other, probably slightly less safety critical, industrial automation systems]

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

#20

Post by Shivetya » Sat, Mar 14, 2015, 3:18 PM UTC

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

surely there are restrictions opening while moving but while stopped seems a bit odd. Aren't they paying the driver to think, to know when to open or not open doors?