ekf2: Save learned magnetometer biases

src/modules/ekf2/ekf2_params.c

@@ -906,3 +906,67 @@ PARAM_DEFINE_FLOAT(EKF2_ANGERR_INIT, 0.1f);
  * @decimal 3
  */
 PARAM_DEFINE_FLOAT(EKF2_RNG_PITCH, 0.0f);
+
+/**
+ * Learned value of magnetometer X axis bias.
+ * This is the amount of X-axis magnetometer bias learned by the EKF and saved from the last flight. It must be set to zero if the ground based magnetometer calibration is repeated.
+ *
+ * @group EKF2
+ * @min -0.5
+ * @max 0.5
+ * @unit mGauss
+ * @decimal 3
+ */
+PARAM_DEFINE_FLOAT(EKF2_MAGBIAS_X, 0.0f);
+
+/**
+ * Learned value of magnetometer Y axis bias.
+ * This is the amount of Y-axis magnetometer bias learned by the EKF and saved from the last flight. It must be set to zero if the ground based magnetometer calibration is repeated.
+ *
+ * @group EKF2
+ * @min -0.5
+ * @max 0.5
+ * @unit mGauss
+ * @decimal 3
+ */
+PARAM_DEFINE_FLOAT(EKF2_MAGBIAS_Y, 0.0f);
+
+/**
+ * Learned value of magnetometer Z axis bias.
+ * This is the amount of Z-axis magnetometer bias learned by the EKF and saved from the last flight. It must be set to zero if the ground based magnetometer calibration is repeated.
+ *
+ * @group EKF2
+ * @min -0.5
+ * @max 0.5
+ * @unit mGauss
+ * @decimal 3
+ */
+PARAM_DEFINE_FLOAT(EKF2_MAGBIAS_Z, 0.0f);
+
+/**
+ * ID of Magnetometer the learned bias is for.
+ *
+ * @group EKF2
+ */
+PARAM_DEFINE_INT32(EKF2_MAGBIAS_ID, 0);
+
+/**
+ * State variance assumed for magnetometer bias storage.
+ * This is a reference variance used to calculate the fraction of learned magnetometer bias that will be used to update the stored value. Smaller values will make the stored bias data adjust more slowly from flight to flight. Larger values will make it adjust faster.
+ *
+ * @group EKF2
+ * @unit mGauss**2
+ * @decimal 8
+ */
+PARAM_DEFINE_FLOAT(EKF2_MAGB_VREF, 2.5E-7f);
+
+/**
+ * Maximum fraction of learned mag bias saved at each disarm.
+ * Smaller values make the saved mag bias learn slower from flight to flight. Larger values make it learn faster. Must be > 0.0 and <= 1.0.
+ *
+ * @group EKF2
+ * @min 0.0
+ * @max 1.0
+ * @decimal 2
+ */
+PARAM_DEFINE_FLOAT(EKF2_MAGB_K, 0.2f);