Brakes do not release when using custom brake and rolling values

[FireStorm525]

Describe the bug
After coming to a stop with the brakes still applied the train cannot start moving again and instantly starts slipping.

How to reproduce
Steps to reproduce the unwanted behavior:

1. use any type of rolling stock from German Voxel Pack
2. get moving at any speed
3. stop with the brakes applied
4. Watch as the train is cemented into place (does happen in about 8/10 cases)

releasing the brakes before stopping prevents it from happening

Expected behavior
After releasing the brakes the train should be free to move again which is not the case

IR: 1.10
Minecraft: 1.12.2
Forge: 14.23.5.2859

The values used in this case:

brake_shoe_material = CAST_IRON
brake_friction_coefficient = 0.05
rolling_resistance_coefficient = 0.0012
direct_friction_coefficient = 0.18

multipliers in config are all on standard values

[Bastelkorb]

The same issue also occurs in Minecraft 1.16.5.

[cam72cam]

Just to confirm, the brake pipe pressure reduces when you release the brakes?

[FireStorm525]

Yes it does. By ramming into the cemented rolling stock you can somehow unfreeze them.

[FireStorm525]

I was able to find out that direct_friction_coefficient was the value causing this problem to begin with. Maybe that helps pinning that down. Since I removed the value from all rolling stock of GVP it will no longer reproduce with that.