points by 1718627440 7 hours ago | 0 comments
Yeah, that works and has been for a while. I was talking about non-track based safety systems. You can have balises in specific locations, but you can't have them every few centimeters on your whole network.
[–] lxgr 4 hours ago
[–] 1718627440 4 hours ago
Because balises cost money, are payed for by infrastructure companies. Their position needs to be decided a priori, so you can't have the whole resolution on the whole network in order to get as close to the physical limits between trains as possible. Also it would be nice to be able to implement automatic shunting without additional infrastructure costs.
[–] djankauskas 6 hours ago
I guess I'm confused by why non track -based solutions are necessary? ETCS L2 would gracefully handle a system restart and automatically force a 40kph speed limit until a train traversed the unknown track proving no occupancy, and allowing proceeding trains to go faster. This all works on a track-based system.
[–] 1718627440 6 hours ago
Because railway infrastucture companies would like to not pay for them, not build more tracks and still get more capacity due to "digitization".
[–] djankauskas 6 hours ago
Not sure what you're arguing, the line affected by this tragedy was migrating to ETCS L2. Its installation costs are getting lower too, I don't think there's an actual problem here.
[–] 1718627440 6 hours ago
I wasn't talking about a specific line at all. Research doesn't need a clear problem to try to find better solutions. Also Deutsche Bahn does think there is enough of a "problem", because they do support that research.
There are also other solutions, e.g. LZB uses a phase change of the signal every 100 meters as an additional precision signal.