MC att control: Add time constant to simplify user-tuning of basic vehicle operation

src/modules/mc_att_control/mc_att_control_params.c

@@ -39,6 +39,28 @@
  * @author Anton Babushkin <anton@px4.io>
  */
 
+/**
+ * Roll time constant
+ *
+ * Reduce if the system is too twitchy, increase if the response is too slow and sluggish.
+ *
+ * @min 0.15
+ * @max 0.25
+ * @group Multicopter Attitude Control
+ */
+PARAM_DEFINE_FLOAT(MC_ROLL_TC, 0.2f);
+
+/**
+ * Pitch time constant
+ *
+ * Reduce if the system is too twitchy, increase if the response is too slow and sluggish.
+ *
+ * @min 0.15
+ * @max 0.25
+ * @group Multicopter Attitude Control
+ */
+PARAM_DEFINE_FLOAT(MC_PITCH_TC, 0.2f);
+
 /**
  * Roll P gain
  *