Attitude Modes

SaVoir supports several attitude modes. They can be edited via the attitude properties grid, or via the attitude wizard.

Attitude Properties	Satellite Wizard

The following parameters can be edited:

• Yaw Steering
• Z-Pointing: It implements an orientation in the satellite Z axis, whether aligned to the planet's center (GEOCENTRIC). perpendicular to the local Nadir (LOCAL_NORMAL), or a combination of yaw steering with pitch steering to implement zero-doppler steering (ZERO_DOPPLER)
• Slew Rate (deg / sec)

  Defines the maximum Slew Rate  that the satellite can sustain during agile operation or right/left slewing (e.g. Cosmo Skymed). The Slew Rate is used to calculate valid transition times during swath calculation, and for 3D model animations.

• Slew Acceleration (deg / sec^2)

  Defines the maximum slew acceleration when steering the satellite for re pointing.

• Default Pointing

  Defines the default pointing for 3D model animations when the satellite is idle, not looking at a swath target. By default the satellite will look at NADIR, but for some satellites it can look at Right or Left (e.g. Cosmo-Skymed, TerraSAR-C, etc).

• Slew Right and Slew Left (deg)

  Defines the nominal left and right slew angles. It is used for satellites with nominal left and right slew looking sides, like Cosmo Skymed, TerraSAR-X, KOMPSAT-5, etc.

• Agile

  Agile satellites perform body pointing manoeuvres to widen the sensors field of regard. Defining a satellite as agile will be used in SaVoir for activating slew controls for transition time check and 3D Model animation. Agile body pointing manoeuvres are constrained by the Slew Rate defined above. The following parameters define further the agility boundaries:

  • Maximum Cross-Track Aperture (degrees): Maximum off-Nadir pointing in the cross track plane. If, for example, an angle of 30 degrees is defined the satellite will be capable of slewing +- 30 degrees in the cross-track plane.
  • Maximum Along-Track Aperture (degrees): Maximum off-Nadir pointing in the along track plane.
• Roll Steering
• Slew Plan
• Attitude File
• Offset: It implements optional fix attitude offsets to Yaw, Pitch or Roll