Sea Trial - Simrad Robertson AP9 Mk3 Instruction Manual

Robertson AP9 Mk3 Autopilot
5.20

Sea Trial

The purpose of the sea-trial is to test the steering characteristics of the
vessel during manoeuvring and cruising and adjust the autopilot
parameters for optimum steering performance.
The steering characteristic varies from vessel to vessel, due to hull
construction, speed, rudder type/size etc. It is therefore important to
observe the behaviour of the vessel for rudder commands (amount
and duration) when steering the vessel by hand (HELMSMAN) on a
fixed heading and when making course changes and turns. The
autopilot parameters should be adjusted to perform the steering with
as few rudder commands as possible, and with as little rudder
deflection as possible.
The following guide lines may be of use to adjust the parameters:
Steering on a fixed heading
Before switching the autopilot to AUTO function, set the parameters
as follows:
• Control Unit parameters:
The Weather parameter will set the sensitivity deadband for minimum when
Note !
OFF (sensitivity deadband controlled by the rudder deadband). By
increasing the WEATHER from OFF to a value, the displayed value is the
maximum sensitivity in degrees.
• INFO loop I parameters:
• INFO loop II
5-62
Counter Rudder
Rudder
Weather
Turn Rate
Radius/Rot
Rudder lim
Off Course
Autotrim
set the
Deadband
Min. Rudder
Serv. speed
Speed sens.
Min. Radius
1
1
OFF (See note)
appr. 50°/minute
Set to Turn Rate
appr. 15°
15°
Initial OFF. When steering
parameters has been adjusted,
Autotrim to 1
0,6 – 0,8°
OFF
Set to ship's relevant speed
0,3
0,05 nm (≈140°/m)
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