Package org.orekit.attitudes

This package provides classes to represent simple attitudes.

See:
Description

Interface Summary

AttitudeLaw	This interface has been created to represent a generic attitude provider without an interval of validity: the attitude can be computed at any date.
AttitudeLawModifier	This interface represents an attitude law that modifies/wraps another underlying law.
AttitudeLeg	Interface which makes it obligatory to give an interval of validity to an attitude law. All the classes implementing this interface should have an interval of validity with CLOSED endpoints.
AttitudeProvider	This interface represents an attitude provider model set.
IOrientationLaw	This interface represents an orientation law, i.e.
Slew	This interface represents a slew model set.

Class Summary

AbstractAttitudeEphemerisGenerator	This abstract class handles the generation of attitude ephemeris from an attitude laws sequence AttitudeLegsSequence. The ephemeris generation can be done using a fixed time step or a variable time step, setting the generation time interval (the default value is the time interval of the sequence), and the treatment to apply to the transition points of the sequence (ignore them, compute the attitude of the initial date of the laws, compute the attitude of the initial and final date of the laws).
AbstractAttitudeLaw	This abstract class gather all common features to classes implementing the AttitudeLaw interface.
AbstractIsisSpinBiasSlew	Abstract class for ISIS spin bias slew: slew with trapezoidal angular velocity profile.
AbstractSlew	This abstract class is the basic implementation of the Slew interface.
Attitude	This class handles attitude definition at a given date.
AttitudeChronologicalComparator	This class is a comparator used to compare the Attitude objects in the ephemeris set.
AttitudeFrame	This class is a special implementation of the Frame class; it represents a dynamic spacecraft frame, i.e.
AttitudeLawLeg	This class represents an attitude law version "attitude", with an interval of validity (whose borders are closed points).
AttitudeLegLaw	This class represents an attitude law version "attitudeLeg", with an interval of validity (whose borders are closed points) and attitude laws outside this interval of validity.
AttitudeLegsSequence	This class handles a sequence of different attitude providers AttitudeLeg.
AttitudesSequence	This classes manages a sequence of different attitude providers that are activated in turn according to switching events.
AttitudeTransformProvider	This class is a TransformProvider for AttitudeFrame; it provides, for a given date, the transformation corresponding to the spacecraft reference frame orientation with respect to the parent frame.
BodyCenterGroundPointing	This class handles body center pointing attitude provider; the difference between BodyCenterPointing and this class is that the target point of the former is the body center, while that of the latter is the corresponding point on the ground.
BodyCenterPointing	This class handles body center pointing attitude provider.
CelestialBodyPointed	This class handles a celestial body pointed attitude provider.
ComposedAttitudeLaw	This class represents a composed attitude law, defined by a main attitude law provider and a chained list of orientation laws. The main attitude law provides, for a given date, the dynamic frame representing the spacecraft orientation; this orientation is then progressively transformed using the orientation laws.
ConstantAttitudeLaw	This class handles a constant attitude law.
ConstantSpinSlew	This class extends the AbstractSlew.
DirectionTrackingOrientation
FixedRate	This class handles a simple attitude provider at constant rate around a fixed axis.
FixedStepAttitudeEphemerisGenerator	This class handles the generation of attitude ephemeris from an attitude laws sequence AttitudeLegsSequence, using a fixed time step. The ephemeris generation can be done setting the generation time interval (the default value is the time interval of the sequence), and the treatment to apply to the transition points of the sequence (ignore them, compute the attitude of the initial date of the laws, compute the attitude of the initial and final date of the laws).
GroundPointing	Base class for ground pointing attitude providers.
GroundPointingWrapper	This class leverages common parts for compensation modes around ground pointing attitudes.
IsisAnalyticalSpinBiasSlew	ISIS spin bias slew: slew with trapezoidal angular velocity profile.
IsisNumericalSpinBiasSlew	ISIS spin bias slew: slew with trapezoidal angular velocity profile.
IsisSunPointing	Implementation of ISIS Sun pointing attitude law.
LofOffset	Attitude law defined by fixed Roll, Pitch and Yaw angles (in any order) with respect to a local orbital frame.
LofOffsetPointing	This class provides a default attitude provider.
NadirPointing	This class handles nadir pointing attitude provider.
OrientationFrame	This class is a special implementation of the Frame class; it represents a dynamic orientation frame, i.e.
OrientationTransformProvider	This class is a TransformProvider for OrientationFrame; it provides, for a given date, the transformation corresponding to the frame orientation with respect to the parent frame.
RelativeTabulatedAttitudeLaw	This class represents a relative tabulated attitude law version "attitudeLeg", with an interval of validity (whose borders are closed points) and attitude laws outside this interval of validity, which can be of two types : a ConstantAttitudeLaw, or an ExtrapolatedAttitudeLaw (private class)
RelativeTabulatedAttitudeLeg	This class implements the tabulated attitude leg relative to a reference date.
SpinStabilized	This class handles a spin stabilized attitude provider.
SunPointing	This class implements a Sun pointing attitude law.
TabulatedAttitude	This class implements the tabulated attitude leg.
TargetGroundPointing	This class handles target pointing attitude provider; while the class TargetPointing does not guarantee the target point belongs to the body surface, this class always provides a ground point target.
TargetPointing	This class handles target pointing attitude provider.
TwoDirectionsAttitude	This class implements a generic two directions attitude law.
TwoSpinBiasSlew	This class extends the AbstractSlew.
VariableStepAttitudeEphemerisGenerator	This class handles the generation of attitude ephemeris from an attitude laws sequence AttitudeLegsSequence, using a variable time step. The ephemeris generation can be done setting the generation time interval (the default value is the time interval of the sequence), and the treatment to apply to the transition points of the sequence (ignore them, compute the attitude of the initial date of the laws, compute the attitude of the initial and final date of the laws).
YawCompensation	This class handles yaw compensation attitude provider.
YawSteering	This class handles yaw steering law.

Enum Summary

ConstantSpinSlew.Constraint	Enumeration of the existing constraint types
RelativeTabulatedAttitudeLaw.AroundAttitudeType	Enumeration of the existing constraint types

Package org.orekit.attitudes Description

This package provides classes to represent simple attitudes.

Some force models such as the atmospheric drag or the maneuvers need to know the spacecraft orientation in inertial frame. OREKIT uses a simple container for Attitude which includes both the geometric part (i.e. rotation) and the kinematic part (i.e. the instant spin axis). The components hold by this container allow to convert vectors from inertial frame to spacecraft frame along with their derivatives. This container is similar in spirit to the various extensions of the abstract Orbit class: it represents a state at a specific instant.

Several classical attitude laws are already provided in this package. One special implementation is the AttitudesSequence class which handle a set of laws, only one of which being active at any time. The active law changes as switch events are triggered.

Author:

Fabien Maussion, Luc Maisonobe, Véronique Pommier-Maurussane