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Rudder

The Rudder shows the angle of a rudder on a half-circle scale, with port to the left and starboard to the right. It is found in the Maritime - OpenBridge section of the Perspective Component Palette as Rudder.

Rudder at 12° with a setpoint at 20°

The parts of the instrument:

  1. Scale — from -maxAngle to maxAngle, with zero at the bottom. See Range.
  2. Value — the rudder angle, as a bar from zero or as a needle. See Angle.
  3. Setpoint — the ordered angle. See Setpoint.

The Rudder is one of the maritime instruments. State, priority, the setpoint, advice zones, the scale and sizing are shared by all of them and are described in Maritime Instruments — Common Features. This page covers what is specific to the Rudder. For a small symbol of the rudder, see the Rudder Indicator.

A Rudder dropped from the palette spans ±90° and has no labels:

Rudder with default properties

Bind angle to the rudder angle in degrees. Positive is starboard (to the right), negative is port (to the left).

variant selects how the angle is shown:

variant Starboard (12) Port (-30)
bar (default) Bar variant Bar variant, port
needle Needle variant Needle variant, port

The bar fills the scale from zero to the angle. The needle is a pointer from the centre, as on a traditional rudder angle indicator.

Name Description Property Type
angle Rudder angle in degrees; positive is starboard. Default 0. value
variant bar or needle. Default bar. value

maxAngle is the largest angle of the scale, to each side. Set it to the mechanical limit of the rudder.

35 45
Rudder with a 35° range Rudder with a 45° range
90 (default)
Rudder with a 90° range

A scale with a small range is a short arc that leaves much of the box empty. Set zoomToFitArc to true to enlarge the arc so that it fills the box. The blue frame is the component’s box:

zoomToFitArc = false zoomToFitArc = true
Arc at its normal size Arc enlarged to fill the box
Name Description Property Type
maxAngle Largest angle of the scale, to each side. Default 90. value
zoomToFitArc Enlarge the arc to fill the box. Default false. value

These work in the same way on every maritime instrument, and are described in Maritime Instruments — Common Features:

  • State — state.
  • Priority — priority.
  • Setpoint — hasSetpoint, setpoint, autoAtSetpoint, autoAtSetpointDeadband, atSetpoint, touching, hasNewSetpoint, newSetpoint, animateSetpoint, setpointAtZeroDeadband, setpointOverride.
  • Advice Zones — advices, with minAngle and maxAngle in degrees.
  • Scale — showLabels, tickmarksInside, tickmarkStyle.
  • Size — hasFaceDiameter, faceDiameter.
  • Style and Events — style.

The Rudder has no component events of its own.

Example 1 — Rudder with Order and Limits

Section titled “Example 1 — Rudder with Order and Limits”
  1. Drop a Rudder into the view and make it about 300 px wide.

  2. Set maxAngle to 35, showLabels to true and zoomToFitArc to true.

  3. Bind angle to [default]Steering/RudderAngle.

  4. Set hasSetpoint to true and bind setpoint to [default]Steering/RudderOrder. Set autoAtSetpoint to true and autoAtSetpointDeadband to 1.

  5. To mark the range beyond 30° as one to be careful with, set advices to:

    [
    {"minAngle": 30, "maxAngle": 35, "type": "caution", "hinted": false},
    {"minAngle": -35, "maxAngle": -30, "type": "caution", "hinted": false}
    ]

Built on the OpenBridge Design System