pbio/drivebase: Prioritize heading on stall.

Partially fixes pybricks/support#1032

Author: laurensvalk

CHANGELOG.md

@@ -11,6 +11,8 @@
   time ([support#1022]).
 - Fixed iterator for `Matrix` objects giving bad values.
 - Fixed Bluetooth sometimes locking up on Technic/City hubs ([support#567]).
+- Fixed `GyroDriveBase` being slow to respond to heading perturbations when
+  driving at high speed ([support#1032]).
 
 ### Added
 - Added `pybricks.geometry.cross(a, b)` to get a vector cross product.
@@ -37,6 +39,7 @@
 [support#992]: https://github.com/pybricks/support/issues/992
 [support#1022]: https://github.com/pybricks/support/issues/1022
 [support#1026]: https://github.com/pybricks/support/issues/1026
+[support#1032]: https://github.com/pybricks/support/issues/1032
 
 ## [3.3.0b3] - 2023-03-28
 

lib/pbio/src/drivebase.c

@@ -106,6 +106,11 @@ static void drivebase_adopt_settings(pbio_control_settings_t *s_distance, pbio_c
     // diameter, the wheels are often quite close together, so this
     // compensates by setting it at 33% instead of 40%.
     s_heading->speed_default = s_heading->speed_max / 3;
+
+    // Most users intuitively expect heading control to take priority. When
+    // heading controller is completely saturated, this ensures that it "wins"
+    // against the distance controller.
+    s_heading->actuation_max = s_distance->actuation_max * 2;
 }
 
 /**