I'm trying out the PBS in 0.7 and tried to build a 3-track with a multi way lane.
Trains do switch to the multiway lane, but only when the train in front of it is:
1. running (not standing still)
2. not just exiting the current track segment
for examle the trains currently don't take the green way:
At a guess, I'd say it's because the train can't find a path back to the lane it started on without having to go through too many rear-facing PBS signals. If the train had broken down before the signal that it had just past, the train behind it probably would have taken the green path and then cut in front of the broken down train.
Try putting signals facing each way on each block, even if there's a 1-way signal at the other end. It just means that the two paths have a more equal penalty when the train gets to a junction.
Yes it's because the pathfinder thinks it's still better to wait for the track to clear than take another route. Adjust PBS penalties in the configuration to remedy. (either increase the penalty for reserved track or decrease the penalties for passing a signal from the back, etc.)
Thanks for the replies, will try all the things mentioned.
Considering adjusting the PBS penalties: does this also work online? Or is this overriden by the server settings?
Sorry for grave-digging, but this topic is worthwhile to bring back up. Recently, I was looking at how to solve the issue of mixing slow/local/freight and express trains on the same double-tracked line in my game and experimented with several possible solutions:
First came the classic approach which temporarily moves slower trains to a siding, and lets faster ones long-reserve through the section. In theory, this should work and scale well, but this leads to awful stop-and-go traffic as the ATC patch is not yet part of JGRpp. Sidings placed at shorter intervals would help, though then I could as well just lay four tracks everywhere, right? Kind of pointless and looks ugly too, if you ask me.
The second approach was to have bi-directional blocks of double track, which is if I'm informed correctly quite common throughout Europe. Let's just say the result was less than satisfactory, in part because the passing maneuvers in this case (112 vs. 160 kph) need a long stretch of track. Another factor was me setting it up with slot operations, of which one would need quite a few given the number of overtake sections.
On the other hand, having a bi-directional track in the middle seems to work relatively well assuming there aren't too many express trains using the line. Sections can be any length and signalling is relatively simple to implement; no need for slots or anything fancy. The primary issue was pathfinding: if the "slow" track isn't penalized enough ("medium penalty" = 2000), they won't use it unless there's something slower directly in front of them, and when the penalty is too high ("large penalty" = 8000), deadlocks may occur. Yes, I know about YAPP's settings, but these are stored locally in openttd.cfg and not the scenario/savegame. Based on my observations, trains prefer to use the middle lane and get out of the way if required, then switch back at the next opportunity. Occasionally, a path through or to the middle lane might become too expensive regardless due to other penalties (number of switches to traverse, sharp curves etc), but this can be solved with a bit of troubleshooting, tweaking the track layout and route restrictions.
It's possible to have more than one train traveling in the same direction with two-way block signals (same concept as busy single-track), though one would need one slot per direction per section of overtaking lane. So yeah, lots of work...
Hope this was of interest to anybody. Probably not perfect by any stretch of the imagination, however!
