Operation Manual
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System conguration | AP70/AP80 Installation Manual
3. Make some small and bigger heading changes to port and starboard and observe how the
vessel settles on the new heading
- The vessel should have a minimum of overshoot (see example “Manual tuning” on page
56
If the autopilot is not keeping the heading satisfactorily or not making the turns satisfactorily,
you may now either try the Autotune function or go directly to Manual tuning.
¼ Note: If the vessel is more than approximately 30 m/100 ft it may be unpractical to perform
Autotune, and it is suggested to proceed with manual tuning.
Both Autotune and Manual tuning should be performed in calm or moderate sea conditions.
Autotuning
When performing an Autotune, the vessel will automatically be taken through a number of
S-turns. Based on the vessel behavior, the autopilot will automatically set the most important
steering parameters (Rudder and Counter rudder). The scaling factors for the parameters are
set automatically as a function of the set boat type.
1. Stabilize the vessel on a heading
2. Set the speed is as close to cruising speed as possible
3. Start autotuning from the dialog
- The pilot will take control of the vessel. Autotuning may take up to 3 minutes to complete
After the autotuning is completed the autopilot will return to STBY mode, and the rudder
must be controlled manually.
¼ Note: Autotuning can be stopped at any time by selecting Cancel.
Manual tuning
1. Stabilize the vessel on a heading, and then select AUTO mode
2. Set the speed as close to cruising speed as possible
3. Activate the Quick menu by pressing the MENU key
4. Select Rudder and adjust according to the description below
5. If required, adjust slightly Counter rudder
Rudder
This parameter determines the ratio between commanded rudder and the heading error. The
higher rudder value the more rudder is applied.
A. The the value is set too high. Steering becomes unstable and often the overshoot will
increase
B. Rudder is too small. It will take a long time to compensate for a heading error, and the
autopilot will fail to keep a steady course
A B
• Range: 0.05 - 4.00
• Default: Defined by system based on boat type and length
Counter rudder
Counter rudder is the amount of counteracting (opposite) rudder applied to stop the turn at
the end of a major course change.
The settings depends on vessel’s characteristics, loaded/ballast conditions and rate of turn.
• If the vessel has good dynamic stability, relatively small settings will be sufficient
• An unstable vessel will require high settings