Package gaiasky.util.gaia

Class AttitudeConverter

java.lang.Object

gaiasky.util.gaia.AttitudeConverter

public class AttitudeConverter
extends Object

Constructor Summary

Constructors

Constructor	Description
AttitudeConverter()

Method Summary

Modifier and Type	Method	Description
static HeliotropicAnglesRates	getHeliotropicAnglesRates(long gt, IAttitude att)	Calculate the heliotropic angles and rates for a given attitude
static QuaternionDouble[]	getQuaternionAndRate(long gt, HeliotropicAnglesRates h)	Converts heliotropic angles and rates to an attitude quaternion and its derivative
static QuaternionDouble[]	heliotropicToQuaternions(double lSun, double xi, double nu, double omega, double lSunDot, double nuDot, double omegaDot)	Converts heliotropic angles and rates to an attitude quaternion and its derivative
static double[]	heliotropicToQuaternionSrsRates(double lSun, double xi, double nu, double omega, double lSunDot, double nuDot, double omegaDot)	Converts heliotropic angles and rates to the attitude quaternion components and the inertial rates in SRS

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

AttitudeConverter

public AttitudeConverter()

Method Details

heliotropicToQuaternions

public static QuaternionDouble[] heliotropicToQuaternions(double lSun,
 double xi,
 double nu,
 double omega,
 double lSunDot,
 double nuDot,
 double omegaDot)

Converts heliotropic angles and rates to an attitude quaternion and its derivative

Parameters:

lSun - longitude of the nominal sun [rad]

xi - solar aspect angle [rad]

nu - revolving phase angle [rad]

omega - scan phase angle [rad]

lSunDot - time derivative of lSun [rad/day]

nuDot - time derivative of nu [rad/day]

omegaDot - time derivative of omega [rad/day]

Returns:

an array of two quaternions, q (the attitude quaternion) and qDot (the time derivative of q, per day)

heliotropicToQuaternionSrsRates

public static double[] heliotropicToQuaternionSrsRates(double lSun,
 double xi,
 double nu,
 double omega,
 double lSunDot,
 double nuDot,
 double omegaDot)

Converts heliotropic angles and rates to the attitude quaternion components and the inertial rates in SRS

Parameters:

lSun - longitude of the nominal sun [rad]

xi - solar aspect angle [rad]

nu - revolving phase angle [rad]

omega - scan phase angle [rad]

lSunDot - time derivative of lSun [rad/day]

nuDot - time derivative of nu [rad/day]

omegaDot - time derivative of omega [rad/day]

Returns:

double[] array {qx, qy, qz, qw, rateX, rateY, rateZ} with rates in [rad/day]

getQuaternionAndRate

public static QuaternionDouble[] getQuaternionAndRate(long gt,
 HeliotropicAnglesRates h)

Converts heliotropic angles and rates to an attitude quaternion and its derivative

Parameters:

gt - GaiaTime

h - heliotropic angles and their rates in [rad] and [rad/day]

Returns:

an array of two quaternions, q (the attitude quaternion) and qDot (the time derivative of q, per day)

getHeliotropicAnglesRates

public static HeliotropicAnglesRates getHeliotropicAnglesRates(long gt,
 IAttitude att)

Calculate the heliotropic angles and rates for a given attitude

Parameters:

gt - Time for the attitude

att - attitude