LL4 IMU Updates from Limelight OS 2025.1

yall/java/limelight/networktables/LimelightSettings.java

@@ -63,6 +63,10 @@ public class LimelightSettings
    * Imu Mode for the Limelight 4.
    */
   private NetworkTableEntry imuMode;
+  /**
+   * Imu Assist Alpha value for the Limelight 4.
+   */
+  private NetworkTableEntry imuAssistAlpha;
   /**
    * Sets 3d offset point for easy 3d targeting Sets the 3D point-of-interest offset for the current fiducial pipeline.
    * <p>
@@ -109,6 +113,7 @@ public LimelightSettings(Limelight camera)
     streamMode = limelightTable.getEntry("stream");
     cropWindow = limelightTable.getDoubleArrayTopic("crop").getEntry(new double[0]);
     imuMode = limelightTable.getEntry("imumode_set");
+    imuAssistAlpha = limelightTable.getEntry("imuassistalpha_set");
     robotOrientationSet = limelightTable.getDoubleArrayTopic("robot_orientation_set").getEntry(new double[0]);
     downscale = limelightTable.getEntry("fiducial_downscale_set");
     fiducial3DOffset = limelightTable.getDoubleArrayTopic("fiducial_offset_set").getEntry(new double[0]);
@@ -197,6 +202,20 @@ public LimelightSettings withImuMode(ImuMode mode)
     return this;
   }
 
+  /**
+   * Set the IMU Assist filter alpha/strength value. Higher values will cause the internal imu to converge on
+   * assist source more rapidly.
+   * <p> This method changes the Limelight - normally immediately.
+   *
+   * @param alpha Assist alpha value (0.001 by default).
+   * @return {@link LimelightSettings} for chaining.
+   */
+  public LimelightSettings withImuAssistAlpha(double alpha)
+  {
+    imuAssistAlpha.setNumber(alpha);
+    return this;
+  }
+
   /**
    * Set the current robot {@link Orientation3d} (normally given by the robot gyro) for LL to use in its MegaTag2
    * determination.
@@ -370,7 +389,15 @@ public enum ImuMode
     /**
      * Use internal IMU for MT2 localization. Ignores external IMU updates from {@link LimelightSettings#withRobotOrientation(Orientation3d)}.
      */
-    InternalImu
+    InternalImu,
+    /**
+     * Use internal IMU for MT2 localization. The internal IMU will utilize filtered MT1 yaw estimates for continuous heading correction.
+     */
+    InternalImuMT1Assist,
+    /**
+     * Use internal IMU for MT2 localization. The internal IMU will utilize the external IMU for continuous heading correction.
+     */
+    InternalImuExternalAssist
   }
 
 }

yall/python/yall/limelight.py

@@ -709,6 +709,8 @@ class ImuMode(Enum):
         ExternalImu = 0  # Use external IMU yaw submitted via {@link withRobotOrientation} for MT2 localization. The internal IMU is ignored entirely.
         SyncInternalImu = 1  # Use external IMU yaw submitted via {@link withRobotOrientation} for MT2 localization. The internal IMU is synced with the external IMU.
         InternalImu = 2  # Use internal IMU for MT2 localization. Ignores external IMU updates from {@link withRobotOrientation}.
+        InternalImuMT1Assist = 3  # Use internal IMU for MT2 localization. The internal IMU will utilize filtered MT1 yaw estimates for continuous heading correction.
+        InternalImuExternalAssist = 4  # Use internal IMU for MT2 localization. The internal IMU will utilize the external IMU for continuous heading correction.
 
     class DownscalingOverride(Enum):
         Pipeline = 0  # Pipeline downscaling, equivalent to 0
@@ -747,6 +749,9 @@ def __init__(self, camera: "Limelight"):
         self.imuMode: ntcore.NetworkTableEntry = self.limelightTable.getEntry(
             "imumode_set"
         )
+        self.imuAssistAlpha: ntcore.NetworkTableEntry = self.limelightTable.getEntry(
+            "imuassistalpha_set"
+        )
         self.robotOrientationSet: ntcore.DoubleArrayEntry = (
             self.limelightTable.getDoubleArrayTopic("robot_orientation_set").getEntry(
                 []
@@ -803,6 +808,15 @@ def withImuMode(self, mode: ImuMode) -> "LimelightSettings":
         self.imuMode.setDouble(mode.value)
         return self
 
+    def withImuAssistAlpha(self, alpha: float) -> "LimelightSettings":
+        """
+        Set the IMU Assist filter alpha/strength value.
+        Higher values will cause the internal imu to converge on assist source more rapidly.
+        Default value is 0.001.
+        """
+        self.imuAssistAlpha.setDouble(alpha)
+        return self
+
     def withRobotOrientation(self, orientation: Orientation3d) -> "LimelightSettings":
         """Set the robot orientation used for localization."""
         self.robotOrientationSet.set(LimelightUtils.orientation3dToArray(orientation))