Class SpiceLibrary

Namespace

NominalSystems.Universe

Assembly

NominalSystems.Universe.dll

[Nominal] Interfaces with NASA SPICE library and is able to fetch the current ephemeris and time information from SPICE. All functions involving SPICE are thread-safe and require a lock to make them thread-safe.

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public static class SpiceLibrary

Inheritance

object

SpiceLibrary

Methods

GetCelestialFrame(string, ref string, ref int)

Returns the celestial frame name and code from a particular target. This is required for some basic calculations using the SPICE system.

public static void GetCelestialFrame(string target, ref string frame, ref int code)

Parameters

target string

The target name to fetch, if valid

frame string

The coordinate frame name of the body

code int

The coordinate frame code of the body

GetCelestialState(string, double, string, string, string, ref Vector3, ref Vector3, ref Matrix3, ref Matrix3, ref double)

Calculates the celestial state of an object, including the position, velocity, rotation and rotation rate, based on some parameters to pass into the SPICE kernels. This requires a few inputs based on the current time of the simulation and the target object.

public static void GetCelestialState(string target, double time, string zeroBase, string bodyFrame, string coordinateFrame, ref Vector3 position, ref Vector3 velocity, ref Matrix3 j2000, ref Matrix3 j2000dot, ref double lightTime)

Parameters

target string

[-] The target name using the SPICE name that is required

time double

[s] The time since the epoch start

zeroBase string

[-] The name of the zero base used for the coordinate frame

bodyFrame string

[-] The name of the planet frame for this particular body

coordinateFrame string

[-] The name of the coordinate frame used by this simulation

position Vector3

[m] The position of the body relative to the coordinate frame

velocity Vector3

[m/s] The velocity of the body relative to the coordinate frame

j2000 Matrix3

[-] The rotation of the body relative to the body frame

j2000dot Matrix3

[r/s] The angular velocity of the body relative to the body frame

lightTime double

[s] The time it takes for light to travel from the coordinate frame to the body

GetEphemerisTime(DateTime, ref double, ref string)

Calculates the ephemeris time and ISO 8601 time string from a particular time in the simulation. This is required for some basic calculations using the SPICE system.

public static void GetEphemerisTime(DateTime time, ref double ephemerisTime, ref string iso8601)

Parameters

time DateTime

[-] The datetime to check

ephemerisTime double

[s] The ephemeris time returned

iso8601 string

[-] The datetime string

GetFrameString(CoordinateFrameType, string)

Returns the SPICE frame from a particular coordinate frame. Based on the coordinate frame, this will return the SPICE frame string.

public static string GetFrameString(CoordinateFrameType frame, string zeroBase)

Parameters

frame CoordinateFrameType

A coordinate frame to convert

zeroBase string

The zero base of the frame

Returns

string

The SPICE frame string

GetReferenceFrameRotation(double, string, CoordinateFrameType, CoordinateFrameType)

Returns the rotation between one reference frame and a second reference frame.

public static Vector3 GetReferenceFrameRotation(double time, string zeroBase, CoordinateFrameType fromFrame, CoordinateFrameType toFrame)

Parameters

time double

[s] The J2000 time

zeroBase string

The central body zero base of the system

fromFrame CoordinateFrameType

The original frame

toFrame CoordinateFrameType

The new target frame

Returns

Vector3

The rotation [deg]

GetSpicePlanetDataAtTime(SpicePlanetStateMessage, string, string, string, string, double)

Gets the SPICE planet data at a particular time in J2000 time. This will update the planet state message with the correct position, velocity, and rotation data at a particular time.

public static void GetSpicePlanetDataAtTime(SpicePlanetStateMessage message, string baseFrame, string zeroBase, string name, string frame, double j2000)

Parameters

message SpicePlanetStateMessage

The planet state message

baseFrame string

The base coordinate frame to get the planet data in

zeroBase string

The zero-base frame

name string

The name of the planet

frame string

The frame of the planet

j2000 double

The rotation matrix of the J2000 coordinate

GetTime(double, ref double, ref string, ref double, ref double, ref double, ref int, ref int)

Calculates the state of the current time and epoch based on the simulation and returns the time in various formats. This includes the Julian Date, UTC time, TAI time, GPS time, and the GPS time in seconds, rollovers, and weeks.

public static void GetTime(double j2000Time, ref double jDate, ref string utcTime, ref double taiTime, ref double gpsTime, ref double gpsSeconds, ref int gpsRollovers, ref int gpsWeeks)

Parameters

j2000Time double

[s] The current J2000 time in seconds

jDate double

[s] The Julian time of the epoch

utcTime string

[-] The UTC time string

taiTime double

[s] The Atomic time of the epoch

gpsTime double

[s] The GPS time of the epoch

gpsSeconds double

[s] The GPS seconds in the week

gpsRollovers int

[-] The number of rollovers in GPS time

gpsWeeks int

[-] The number of weeks since last rollover

LoadKernels()

Loads all kernels required

public static void LoadKernels()

UnloadKernels()

Unloads all kernels required

public static void UnloadKernels()