VW: raise minimum steering speed to fix a fault (#31450)

* VW: Steer to zero, for large values of zero

* ah, the joy of floating point

* comment, style

* actually fix floating point issue

* follow PlatformConfig refactor

* this check is not useful after PlatformConfig

* don't really need that

* work around docs assert

* little better

* one comment

* update refs

---------

Co-authored-by: Shane Smiskol <shane@smiskol.com>

selfdrive/car/docs_definitions.py

@@ -266,7 +266,7 @@ class CarDocs:
     # min steer & enable speed columns
     # TODO: set all the min steer speeds in carParams and remove this
     if self.min_steer_speed is not None:
-      assert CP.minSteerSpeed == 0, f"{CP.carFingerprint}: Minimum steer speed set in both CarDocs and CarParams"
+      assert CP.minSteerSpeed < 0.5, f"{CP.carFingerprint}: Minimum steer speed set in both CarDocs and CarParams"
     else:
       self.min_steer_speed = CP.minSteerSpeed
 

selfdrive/car/volkswagen/interface.py

@@ -2,7 +2,7 @@ from cereal import car
 from panda import Panda
 from openpilot.selfdrive.car import get_safety_config
 from openpilot.selfdrive.car.interfaces import CarInterfaceBase
-from openpilot.selfdrive.car.volkswagen.values import CAR, CANBUS, NetworkLocation, TransmissionType, GearShifter, VolkswagenFlags
+from openpilot.selfdrive.car.volkswagen.values import CAR, CANBUS, CarControllerParams, NetworkLocation, TransmissionType, GearShifter, VolkswagenFlags
 
 ButtonType = car.CarState.ButtonEvent.Type
 EventName = car.CarEvent.EventName
@@ -111,7 +111,7 @@ class CarInterface(CarInterfaceBase):
                                        enable_buttons=(ButtonType.setCruise, ButtonType.resumeCruise))
 
     # Low speed steer alert hysteresis logic
-    if self.CP.minSteerSpeed > 0. and ret.vEgo < (self.CP.minSteerSpeed + 1.):
+    if (self.CP.minSteerSpeed - 1e-3) > CarControllerParams.DEFAULT_MIN_STEER_SPEED and ret.vEgo < (self.CP.minSteerSpeed + 1.):
       self.low_speed_alert = True
     elif ret.vEgo > (self.CP.minSteerSpeed + 2.):
       self.low_speed_alert = False

selfdrive/car/volkswagen/values.py

@@ -34,6 +34,8 @@ class CarControllerParams:
   STEER_TIME_ALERT = STEER_TIME_MAX - 10   # If mitigation fails, time to soft disengage before EPS timer expires
   STEER_TIME_STUCK_TORQUE = 1.9            # EPS limits same torque to 6 seconds, reset timer 3x within that period
 
+  DEFAULT_MIN_STEER_SPEED = 0.4            # m/s, newer EPS racks fault below this speed, don't show a low speed alert
+
   ACCEL_MAX = 2.0                          # 2.0 m/s max acceleration
   ACCEL_MIN = -3.5                         # 3.5 m/s max deceleration
 
@@ -159,6 +161,7 @@ class VolkswagenPQPlatformConfig(VolkswagenMQBPlatformConfig):
 class VolkswagenCarSpecs(CarSpecs):
   centerToFrontRatio: float = 0.45
   steerRatio: float = 15.6
+  minSteerSpeed: float = CarControllerParams.DEFAULT_MIN_STEER_SPEED
 
 
 class Footnote(Enum):
@@ -195,6 +198,9 @@ class VWCarDocs(CarDocs):
     if CP.carFingerprint in (CAR.VOLKSWAGEN_CRAFTER_MK2, CAR.VOLKSWAGEN_TRANSPORTER_T61):
       self.car_parts = CarParts([Device.threex_angled_mount, CarHarness.j533])
 
+    if abs(CP.minSteerSpeed - CarControllerParams.DEFAULT_MIN_STEER_SPEED) < 1e-3:
+      self.min_steer_speed = 0
+
 
 # Check the 7th and 8th characters of the VIN before adding a new CAR. If the
 # chassis code is already listed below, don't add a new CAR, just add to the

selfdrive/test/process_replay/ref_commit

@@ -1 +1 @@
-692a21e4a722d91086998b532ca6759a3f85c345
+685a2bb9aacdd790e26d14aa49d3792c3ed65125