Class GeodeticLibrary

Namespace

NominalSystems.Universe

Assembly

NominalSystems.Universe.dll

Library for converting between different planet coordinates, including: PCI, PCPF, LLA and SEZ

public static class GeodeticLibrary

Inheritance

object

GeodeticLibrary

Methods

GeodeticElem2VectorElem(GeodeticElements, Matrix3, double, double)

Converts from a Lat/Long/Altitude coordinates to planet-centered, planet-fixed coordinates given a planet radius. This assumes that the object is located at the peak of the orbit equal to the lat and lon of the object. This also assumes a circular orbit.

public static VectorElements GeodeticElem2VectorElem(GeodeticElements llaPosition, Matrix3 j20002Pfix, double planetRadius, double mu)

Parameters

llaPosition GeodeticElements

[-] Position in latitude/longitude/altitude coordinates

j20002Pfix Matrix3

[-] Planet rotation matrix

planetRadius double

[m] Planetary radius, assumed to be constant (i.e., spherical)

mu double

[kg m^2 s^3] The gravitational constant for the body orbiting

Returns

VectorElements

[m]/[m/s] Final position and velocity in the planet-centered, planet-fixed frame.

LLA2PCI(GeodeticElements, Matrix3, double)

Converts from a planet-centered inertial coordinates to latitutde/longitude/altitude (LLA) coordinates given a planet radius and rotation matrix.

public static Vector3 LLA2PCI(GeodeticElements llaPosition, Matrix3 J20002Pfix, double planetRadius)

Parameters

llaPosition GeodeticElements

[-] Position in latitude/longitude/altitude coordinates

J20002Pfix Matrix3

[-] Rotation matrix between inertial and PCPF frames

planetRadius double

[m] Planetary radius, assumed to be constant (i.e., spherical)

Returns

Vector3

[m] Position in inertial coordinates.

LLA2PCPF(GeodeticElements, double)

Converts from a Lat/Long/Altitude coordinates to planet-centered, planet-fixed coordinates given a planet radius.

public static Vector3 LLA2PCPF(GeodeticElements llaPosition, double planetRadius)

Parameters

llaPosition GeodeticElements

[-] Position in latitude/longitude/altitude coordinates

planetRadius double

[m] Planetary radius, assumed to be constant (i.e., spherical)

Returns

Vector3

[m] Final position in the planet-centered, planet-fixed frame.

PCI2LLA(Vector3, Matrix3, double)

Converts from a planet-centered inertial coordinates to latitutde/longitude/altitude (LLA) coordinates given a planet radius and rotation matrix.

public static GeodeticElements PCI2LLA(Vector3 pciPosition, Matrix3 J20002Pfix, double planetRadius)

Parameters

pciPosition Vector3

[m] Position vector in PCI coordinates

J20002Pfix Matrix3

[-] 3x3 rotation matrix representing the rotation between PCPF and ECI frames

planetRadius double

[m] Planetary radius, assumed to be constant (i.e., spherical)

Returns

GeodeticElements

Final position in latitude/longitude/altitude coordinates [0] : [deg] latitude above planetary equator [1] : [deg] longitude across planetary meridian [2] : [m] altitude above planet radius

PCI2PCPF(Vector3, Matrix3)

Converts from a planet-centered inertial position (i.e., J2000 ECI) to a planet-centered, planet-fixed position given a rotation matrix.

public static Vector3 PCI2PCPF(Vector3 pciPosition, Matrix3 J20002Pfix)

Parameters

pciPosition Vector3

[m] Position vector in PCI coordinates

J20002Pfix Matrix3

[-] 3x3 rotation matrix representing the rotation between PCPF and ECI frames

Returns

Vector3

[m] Position vector in PCPF coordinates

PCPF2LLA(Vector3, double)

Converts from a planet-centered, planet-fixed coordinates to latitutde/longitude/altitude (LLA) coordinates given a planet radius.

public static GeodeticElements PCPF2LLA(Vector3 pcpfPosition, double planetRadius)

Parameters

pcpfPosition Vector3

[m] Position vector in PCPF coordinates

planetRadius double

[m] Planetary radius, assumed to be constant (i.e., spherical)

Returns

GeodeticElements

Final position in latitude/longitude/altitude coordinates [0] : [rad] latitude above planetary equator [1] : [rad] longitude across planetary meridian [2] : [m] altitude above planet radius

PCPF2PCI(Vector3, Matrix3)

Converts from a planet-centered, planet-fixed to a planet-centered inertial position (i.e., J2000 ECI) position given a rotation matrix.

public static Vector3 PCPF2PCI(Vector3 pcpfPosition, Matrix3 J20002Pfix)

Parameters

pcpfPosition Vector3

[m] Position vector in planet centered, planet fixed coordinates

J20002Pfix Matrix3

[-] Rotation between inertial and pcf coordinates.

Returns

Vector3

[m] Final position in the planet-centered inertial frame.

PCPF2SEZ(double, double)

Converts a Latitude and Longitude to South-Easth-Zenith (SEZ) position

public static Matrix3 PCPF2SEZ(double latitude, double longitude)

Parameters

latitude double

[rad] The latitude of the body

longitude double

[rad] The longitude of the body

Returns

Matrix3

A SEZ matrix

WGS2LLA(Vector3)

Converts the WGS parameters to Lat Long Alt

public static GeodeticElements WGS2LLA(Vector3 position)

Parameters

position Vector3

The current PCI position

Returns

GeodeticElements

The Geodetic Elements of the body