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34
N.
NAV L1 Controller Tuning
The Arduplane L1 Navigation Controller controls turns and loiter circles and involves tuning one key
parameter
–
the
NAVL1_PERIOD
(optionally the
NAVL1_DAMPING
parameter can also be adjusted).
1.
Make sure you have already tuned the roll and pitch controllers as per sections above
2.
When in a flight mode that executes a turn, e.g. HOME (RTL - Return to Land) mode, where a
turn is executed by the AUTOPILOT, either in turning back to the HOME location, or acquiring
and remaining within a loiter circle, observe the behavior.
3.
When back on the ground make the following adjustments (alternatively, an in-flight tuning kit is
available to modify parameters in flight).
If the aircraft turns too slowly then reduce
NAVL1_PERIOD
by 2 - 5. If it is weaving after a turn,
then increase
NAVL1_PERIOD
by 1 or 2
NAVL1
NAVL1_PERIOD
NAV L1 Controller period (seconds) (default =
24
)
NAVL1
NAVL1_DAMPING
NAV L1 Controller damping (default =
0.76
)
If you want the aircraft to smoothly acquire and maintain the loiter circle, then set
RTL_RADIUS
to a larger number. A good starting value is to set it equal to the turn radius your aircraft can
easily achieve.
The
NAVL1_DAMPING
parameter enables additional damping to be specified to compensate for
delays in the velocity measurement and aircraft roll response.
4.
In order properly anticipate Waypoint turns, make sure your Waypoint radius parameters are
correctly setup, e.g.:
WP -> WP_RADIUS
1609
WP radius in meters
Note 1,609 meters = 1 mile
Additional details are available here:
http://ardupilot.org/plane/docs/navigation-tuning.html