CovarianceDisplay - Zudokakikuto/OreCZML GitHub Wiki

This page describes the content of a CZML document. Please read Get Started for an explanation of how a CZML document is put together.

Covariance Display

Implements : CzmlPrimaryObject

Extends : AbstractPrimaryObject

Example :

{
    "id":"COV/Keplerian parameters: {a: 7878000.0; e: 0.0; i: 20.0; pa: 0.0; raan: 0.0; v: 0.0;}[2460384:43200 UTC (03/15/2024 00:00:00), 2460384:43260 UTC (03/15/2024 00:01:00), 2460384:43320 UTC (03/15/2024 00:02:00), 2460384:43380 UTC (03/15/2024 00:03:00), 2460384:43440 UTC (03/15/2024 00:04:00), 2460384:43500 UTC (03/15/2024 00:05:00), 2460384:43560 UTC (03/15/2024 00:06:00), 2460384:43620 UTC (03/15/2024 00:07:00), 2460384:43680 UTC (03/15/2024 00:08:00), 2460384:43740 UTC (03/15/2024 00:09:00)]",
    "name":"Covariance of Keplerian parameters: {a: 7878000.0; e: 0.0; i: 20.0; pa: 0.0; raan: 0.0; v: 0.0;}",
    "orientation":{
      "interval":"2024-03-15T00:00:00Z/2024-03-15T05:00:00Z",
      "epoch":"2024-03-15T00:00:00Z",
      "unitQuaternion":[
        0,0.11569062798938476,0.12952604257194286,0.6509835902071016,-0.7389580828248281,
        60,0.11943577277304293,0.12608039801805412,0.632361993372306,-0.754955057441116,
        120,0.12307773148000348,0.12252573594575572,0.6133475316353406,-0.7704830442530984,
        180,0.12661339981222997,0.11886509438917287,0.593951991730508,-0.785532410434607,
        240,0.13003976644592383,0.11510160480621578,0.5741873930795629,-0.8000938178377701,
        300,0.13335391475857142,0.11123848993382857,0.5540659835669867,-0.814158226409187
        ],
      "interpolationAlgorithm":"LAGRANGE",
      "interpolationDegree":5
    },
    "position":{
      "reference":"Keplerian parameters: {a: 7878000.0; e: 0.0; i: 20.0; pa: 0.0; raan: 0.0; v: 0.0;}#position"
    },
    "ellipsoid":{
      "fill":false,
      "outline":true,
      "outlineColor":{
        "rgba":[
          0,255,0,255
        ]
      },
      "slicePartitions":24,
      "stackPartitions":36,
      "interval":"2024-03-15T00:00:00Z/2024-03-15T05:00:00Z",
      "radii":{
        "epoch":"2024-03-15T00:00:00Z",
        "cartesian":[
          0,999.9999999999995,100.00000000000001,99.99999999999994,
          60,1000.3557088442701,101.24416119580226,100.06558092587828,
          120,1001.4188533345995,105.00577034773143,100.26155105418857,
          180,1003.1789072897213,111.37161616179563,100.58560099177218,
          240,1005.6231038323383,120.48430803609354,101.03391142817493,
          300,1008.7436529447372,132.53872099231185,101.60118284669117
      ]
    }
  }
}

Properties

id - String : Identification of the covariance display object, default : "COV/{id of the object}".

name - String : Name of the covariance display, default : "Covariance of {name of the object}".

availability - TimeInterval : Time interval when the covariance display is displayed.

Intrinsic arguments :

These arguments can be used to build a covariance display object :

satellite - Satellite : The satellite which the covariance display will be around.

initCovariance - StateCovariance : An initial state covariance object to give the propagation of the covariance a initialisation.

lof - LOF : The local orbital frame of the satellite.

color - Color : The color of the ellipsoid used to represents the covariance.

oem - Oem : An Orekit Oem file used as an input.

ephemeris - List of TimeStampedPVCoordinates : A list of TimeStampedPVCoordinates extracted from an Oem or another file, to get the ephemeris.

position - Position : The absolute position of the ellipsoid built with the position object.

ellipsoid - CzmlEllipsoid : The czml ellipsoid object used to built the ellipsoid to be displayed that represents the covariance.

attitude - Attitude : The attitude of the ellipsoid built with an Orkeit Attitude object.

Other parameters

referenceFrame - String : The reference frame where the covariance is computed, default : "INERTIAL".

positionReference - Reference : The reference for the center of the position of the ellipsoid.

orientationReference - Reference : The reference for the orientation of the ellipsoid.

allSpaceCraftState - List of SpacecraftState : A list of all the spacecraft state when the covariance is propagated.

ellipsoidList - List of CzmlEllipsoid : When the covariance changes in time, several ellipsoids are computed, they are stored here.

julianDates - List of JulianDate : A list of all the julian dates when the propagation of the covariance is computed.

dimensionsOfEllipsoids - List of Cartesian : A list of cartesian that represents the radius of the ellipsoids in the ITR frame.

attitudes - List of Attitude : A list of all the attitudes of all the ellipsoids, when the ellipsoid changes in time.

satelliteCartesianList - List of Cartesian : A list that contains all the position in cartesian of the satellite in the ITR frame.

timeScale - TimeScale : The time scale used for the covariance

uniqueEllipsoid - CzmlEllipsoid : The ellipsoid used when only one ellipsoid is needed.

Build

The CovarianceDisplay object can be build with :

A satellite, an initCovariance, a lof :

CovarianceDisplay covariance = new CovarianceDisplay(satellite, initCovariance, lof);

A satellite, an initCovariance, a lof, a color :

CovarianceDisplay covariance = new CovarianceDisplay(satellite, initCovariance, lof, color);

An oem, a lof :

CovarianceDisplay covariance = new CovarianceDisplay(oem, lof);

An oem, a lof, a color :

CovarianceDisplay covariance = new CovarianceDisplay(oem, lof, color);

An ephemeris, an initCovariance, a lof :

CovarianceDisplay covariance = new CovarianceDisplay(ephemeris, initCovariance, lof);

An ephemeris, an initCovariance, a lof, a color :

CovarianceDisplay covariance = new CovarianceDisplay(ephemeris, initCovariance, lof, color);

A position, an ellipsoid, an attitude :

CovarianceDisplay covariance = new CovarianceDisplay(position, ellipsoid, attitude);

An id, a name, a position, an ellipsoid, an attitude :

CovarianceDisplay covariance = new CovarianceDisplay(id, name, position, ellipsoid, attitude);