This page describes the content of a CZMLSecondaryObject document. Please read CZMLSecondaryObject for the intern architecture of CZMLPrimaryObjects.

Orientation

The orientation object can be applied to every CzmlPrimaryObject it defines the attitude of the object in the local orbital frame.

Implements : CZMLSecondaryObject

Example :

"orientation":{
      "interval":"2024-03-15T00:00:00Z/2024-03-15T10:00:00Z",
      "epoch":"2024-03-15T00:00:00Z",
      "unitQuaternion":[
        0,0.44071664380702213,-0.5519036541194844,-0.36872616803372776,0.6043278989490706,
        60,0.4236289664576621,-0.5211570590666941,-0.3797015633509604,0.6362079387682962,
        120,0.40472908606329355,-0.49030247429532786,-0.3883442213193551,0.6670731716701807,
        180,0.3844223418602142,-0.45966489283697753,-0.39448202169175983,0.6966430821689543,
        240,0.36316309508253436,-0.42956661519149336,-0.3980101316718926,0.7246882257698964,
        300,0.3414423477576132,-0.40031399169701387,-0.3988882347732465,0.7510352903618149],
      "interpolationAlgorithm":"LAGRANGE",
      "interpolationDegree":5
}

Properties

Arguments that can be used to build the Orientation object :

singleAttitude - Attitude : The attitude of the object.

attitudes - A list of Attitude : This list contains all the attitudes in time of the object.

objectFrame - Frame : The frame of the object.

optionalRotation - Rotation : An optional rotation that can be added to tilt the object in a certain oritentation.

convertToITRF - boolean : A boolean to choose if the orientation will be expressed in ITRF or not. For a satellite around the earth it must be set to true. Default : true;

Other parameters

unitQuaternion - UnitQuaternion : A UnitQuaternion object, they defines the quaternions that allows the rotation in space of the object, used when a single orientation is built.

multipleQuaternions - List of UnitQuaternion : A list that contains all the UnitQuaternions of the object in time, used when the orientation changes in time.

julianDates - List of JulianDate : All the julian dates when the orientation is computed.

interval - TimeInterval : The interval of time when the object is defined.

interpolationAlgorithm - CesiumInterpolationAlgorithm : The interpolation algorithm, can take the values : "HERMITE", "LAGRANGE" or "LINEAR". They define which kind of algorithm will be used for the interpolation between points. Default : "LAGRANGE".

interpolationDegree - int : The degree used for the interpolation, default : 5.

multipleAttitudes - boolean : This boolean aims at knowing if one or more attitudes are used in input.

Build

These arguments can be used to build a constellation object :

• An Attitude, an objectFrame :

Orientation orientation = new Orientation(attitude, objectFrame);

• An Attitude, an objectFrame, an optionalRotation :

Orientation orientation = new Orientation(attitude, objectFrame, optionalRotation);

• An Attitude, an objectFrame, convertToITRF (boolean) :

Orientation orientation = new Orientation(attitude, objectFrame, convertToITRF);

• An Attitude, an objectFrame, convertToITRF (boolean), an optionalRotation :

Orientation orientation = new Orientation(attitude, objectFrame, convertToITRF, optionalRotation);

• A List of Attitude, an objectFrame :

Orientation orientation = new Orientation(attitudes, objectFrame);

• An List of Attitude, an objectFrame, an optionalRotation :

Orientation orientation = new Orientation(attitudes, objectFrame, optionalRotation);

• An List of Attitude, an objectFrame, convertToITRF (boolean) :

Orientation orientation = new Orientation(attitudes, objectFrame, convertToITRF);

• An List of Attitude, an objectFrame, convertToITRF (boolean), an optionalRotation :

Orientation orientation = new Orientation(attitudes, objectFrame, convertToITRF, optionalRotation);