ION - Waterloo Region's Light Rail Transit

[jamincan]

This is not the first time I have heard of clearly wrong design related to doors. My understanding is that some subway trains, I think including the TTC’s Toronto Rockets, have the following procedure when an obstruction prevents a door from closing: all doors re-open and repeat the closing sequence. If they fail 3 times, the train is out of service. This is totally absurd. What should happen is that only the obstructed door should re-open. This means instead of requiring 24 doors to successfully close simultaneously, maybe 23 close on the first try and the remaining one re-opens and then closes. So right away this would eliminate most of the problems.

This is the way every urban train (that I can think of) works: all the doors open and close in unison. One won't close? All doors will reopen and attempt to close again.

I am not an expert in this, though, so I don't know why this logic is used.

It's standard for any system where the doors opening/closing is automatic for obvious reasons. ION is an example that clearly shows that train manufacturers already have the technology to individually control the doors. You end up trading one problem for another, though. Instead of a simpler system where all doors operate simultaneously, you have a more complicated system that could now fail in some other way.