fr.cnes.sirius.patrius.attitudes

Class AbstractGroundPointingWrapper

java.lang.Object

fr.cnes.sirius.patrius.attitudes.AbstractAttitudeLaw

fr.cnes.sirius.patrius.attitudes.AbstractGroundPointing

fr.cnes.sirius.patrius.attitudes.AbstractGroundPointingWrapper

All Implemented Interfaces:

AttitudeLaw, AttitudeLawModifier, AttitudeProvider, Serializable

Direct Known Subclasses:

YawCompensation, YawSteering

public abstract class AbstractGroundPointingWrapper
extends AbstractGroundPointing
implements AttitudeLawModifier

This class leverages common parts for compensation modes around ground pointing attitudes.

Author:

Véronique Pommier-Maurussane, Luc Maisonobe

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
AbstractGroundPointingWrapper(AbstractGroundPointing pGroundPointingLaw) Creates a new instance.
AbstractGroundPointingWrapper(AbstractGroundPointing pGroundPointingLaw, Vector3D losInSatFrameVec, Vector3D losNormalInSatFrameVec) Creates a new instance with specified los axis in satellite frame.
AbstractGroundPointingWrapper(AbstractGroundPointing pGroundPointingLaw, Vector3D losInSatFrameVec, Vector3D losNormalInSatFrameVec, double targetVelocityDeltaT) Creates a new instance with specified los axis in satellite frame.

Method Summary

Modifier and Type	Method and Description
Attitude	getBaseState(PVCoordinatesProvider pvProv, AbsoluteDate date, Frame frame) Compute the base system state at given date, without compensation.
abstract TimeStampedAngularCoordinates	getCompensation(PVCoordinatesProvider pvProv, AbsoluteDate date, Frame frame, Attitude base) Compute the TimeStampedAngularCoordinates at a given time.
AttitudeLaw	getGroundPointingLaw() Getter for the ground pointing attitude provider without yaw compensation.
protected Vector3D	getTargetPosition(PVCoordinatesProvider pvProv, AbsoluteDate date, Frame frame) Compute the target ground point position in specified frame.
protected TimeStampedPVCoordinates	getTargetPV(PVCoordinatesProvider pvProv, AbsoluteDate date, Frame frame) Compute the target point position/velocity in specified frame.
AttitudeLaw	getUnderlyingAttitudeLaw() Get the underlying (ground pointing) attitude provider.
void	setSpinDerivativesComputation(boolean computeSpinDerivatives) Method to activate spin derivative computation.

Methods inherited from class fr.cnes.sirius.patrius.attitudes.AbstractGroundPointing

getAttitude, getBodyFrame, getBodyShape, getLosInSatFrame, getLosNormalInSatFrame

Methods inherited from class fr.cnes.sirius.patrius.attitudes.AbstractAttitudeLaw

getSpinDerivativesComputation

Methods inherited from class java.lang.Object

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

Methods inherited from interface fr.cnes.sirius.patrius.attitudes.AttitudeProvider

computeSpinByFD, computeSpinDerivativeByFD, getAttitude, getAttitude

Constructor Detail

AbstractGroundPointingWrapper

public AbstractGroundPointingWrapper(AbstractGroundPointing pGroundPointingLaw)

Creates a new instance.

Parameters:

pGroundPointingLaw - ground pointing attitude provider without compensation

AbstractGroundPointingWrapper

public AbstractGroundPointingWrapper(AbstractGroundPointing pGroundPointingLaw,
                                     Vector3D losInSatFrameVec,
                                     Vector3D losNormalInSatFrameVec)

Creates a new instance with specified los axis in satellite frame.

Parameters:

pGroundPointingLaw - ground pointing attitude provider without compensation

losInSatFrameVec - LOS in satellite frame axis

losNormalInSatFrameVec - LOS normal axis in satellite frame

AbstractGroundPointingWrapper

public AbstractGroundPointingWrapper(AbstractGroundPointing pGroundPointingLaw,
                                     Vector3D losInSatFrameVec,
                                     Vector3D losNormalInSatFrameVec,
                                     double targetVelocityDeltaT)

Creates a new instance with specified los axis in satellite frame.

Parameters:

pGroundPointingLaw - ground pointing attitude provider without compensation

losInSatFrameVec - LOS in satellite frame axis

losNormalInSatFrameVec - LOS normal axis in satellite frame

targetVelocityDeltaT - the delta-T used to compute target velocity by finite differences

Method Detail

getUnderlyingAttitudeLaw

public final AttitudeLaw getUnderlyingAttitudeLaw()

Get the underlying (ground pointing) attitude provider.

Specified by:

getUnderlyingAttitudeLaw in interface AttitudeLawModifier

Returns:

underlying attitude provider

getTargetPosition

protected final Vector3D getTargetPosition(PVCoordinatesProvider pvProv,
                                           AbsoluteDate date,
                                           Frame frame)
                                    throws PatriusException

Compute the target ground point position in specified frame.

Specified by:

getTargetPosition in class AbstractGroundPointing

Parameters:

pvProv - provider for PV coordinates

date - date at which target point is requested

frame - frame in which observed ground point should be provided

Returns:

observed ground point position in specified frame

Throws:

PatriusException - if some specific error occurs, such as no target reached

getTargetPV

protected final TimeStampedPVCoordinates getTargetPV(PVCoordinatesProvider pvProv,
                                                     AbsoluteDate date,
                                                     Frame frame)
                                              throws PatriusException

Compute the target point position/velocity in specified frame.

The default implementation use a simple centered two points finite differences scheme, it may be replaced by more accurate models in specialized implementations.

In the case where the point is computed at a date corresponding to the lower/upper bound of the ephemeris, the finite differences scheme used is either 1st order forward or backward.

The calculated intersection velocity corresponds to the "virtual" intersection point velocity between the satellite los and the Earth, not the velocity of the physical point.

Overrides:

getTargetPV in class AbstractGroundPointing

Parameters:

pvProv - provider for PV coordinates

date - date at which target point is requested

frame - frame in which observed ground point should be provided

Returns:

observed ground point position/velocity in specified frame

Throws:

PatriusException - if some specific error occurs, such as no target reached

getBaseState

public final Attitude getBaseState(PVCoordinatesProvider pvProv,
                                   AbsoluteDate date,
                                   Frame frame)
                            throws PatriusException

Compute the base system state at given date, without compensation.

Parameters:

pvProv - provider for PV coordinates

date - date at which state is requested

frame - reference frame from which attitude is computed

Returns:

satellite base attitude state, i.e without compensation.

Throws:

PatriusException - if some specific error occurs

getCompensation

public abstract TimeStampedAngularCoordinates getCompensation(PVCoordinatesProvider pvProv,
                                                              AbsoluteDate date,
                                                              Frame frame,
                                                              Attitude base)
                                                       throws PatriusException

Compute the TimeStampedAngularCoordinates at a given time.

Parameters:

pvProv - provider for PV coordinates

date - date at which rotation is requested

frame - reference frame from which attitude is computed

base - base satellite attitude in given frame.

Returns:

compensation rotation at date, i.e rotation between non compensated attitude state and compensated state.

Throws:

PatriusException - if some specific error occurs

setSpinDerivativesComputation

public void setSpinDerivativesComputation(boolean computeSpinDerivatives)

Method to activate spin derivative computation.

Spin derivatives computation applies to provided law groundPointingLaw.

Specified by:

setSpinDerivativesComputation in interface AttitudeProvider

Overrides:

setSpinDerivativesComputation in class AbstractAttitudeLaw

Parameters:

computeSpinDerivatives - true if spin derivatives should be computed

getGroundPointingLaw

public AttitudeLaw getGroundPointingLaw()

Getter for the ground pointing attitude provider without yaw compensation.

Returns:

the ground pointing attitude provider without yaw compensation