From 6b82f1471aaf38b7417f28c018aa3e1e958416fc Mon Sep 17 00:00:00 2001 From: pwarszawski Date: Mon, 2 Nov 2026 12:36:11 +0100 Subject: [PATCH] AI braking: take power off when holding the speed uphill near a stop Within fMaxProximityDist of a stop, going uphill, the AI holds its speed with AccDesired = min(0, AccPreferred). control_tractive_force only cut the power uphill when AccDesired < 0, so an AccDesired of exactly 0 kept the controller where it was. A consist that came into that range under power kept full power and crept up to the signal. Holding the speed uphill on the way to a stop now asks for no speeding up: power comes off once the train is faster than AccDesired allows. With the current brake valves this rarely shows: on a 10 per mille climb, four real-time runs of 32 consists each, the E186 with 25 empty 408W drew power in 0-14 samples of the last 50 m before and 0-8 after, no overruns either way. It surfaced once the AI predicted the ESt3 brake closer to what the valve delivers, where the same train crept to 12 km/h from 40 m out and overran the signal; with this change it stopped short in all runs. --- vehicle/Driver.cpp | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/vehicle/Driver.cpp b/vehicle/Driver.cpp index 2c59ddcda..436cdb7f6 100644 --- a/vehicle/Driver.cpp +++ b/vehicle/Driver.cpp @@ -8099,7 +8099,9 @@ void TController::control_tractive_force() { } else if( velocity > VelDesired + SpeedCtrlMargin || ( fAccGravity < -0.01 ? - AccDesired < 0.0 : + AccDesired < 0.0 + // holding the speed uphill on the way to a stop asks for no speeding up + || ( VelNext == 0.0 && ActualProximityDist <= fMaxProximityDist && AbsAccS > AccDesired + 0.05 ) : AbsAccS > AccDesired + 10.05 ) || IsAnyCouplerStretched ) { // jak za bardzo przyspiesza albo prędkość przekroczona