org.orekit.attitudes
Class GroundPointingWrapper

java.lang.Object
  org.orekit.attitudes.GroundPointing
      org.orekit.attitudes.GroundPointingWrapper

All Implemented Interfaces:

java.io.Serializable, AttitudeLaw

Direct Known Subclasses:

YawCompensation, YawSteering

public abstract class GroundPointingWrapper
extends GroundPointing

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

Version:

$Revision:1665 $ $Date:2008-06-11 12:12:59 +0200 (mer., 11 juin 2008) $

Author:

Véronique Pommier-Maurussane, Luc Maisonobe

See Also:

Serialized Form

Constructor Summary

GroundPointingWrapper(GroundPointing groundPointingLaw)
Creates a new instance.

Method Summary

Attitude	getAttitude(Orbit orbit) Compute the attitude corresponding to an orbital state.
Attitude	getBaseState(Orbit orbit) Compute the base system state at given date, without compensation.
abstract org.apache.commons.math.geometry.Rotation	getCompensation(Orbit orbit, Attitude base) Compute the compensation rotation at given date.
GroundPointing	getGroundPointingLaw() Get the attitude rotation.
protected org.apache.commons.math.geometry.Vector3D	getTargetPoint(Orbit orbit, Frame frame) Compute the target point in specified frame.
protected PVCoordinates	getTargetPV(Orbit orbit, Frame frame) Compute the target point position/velocity in specified frame.

Methods inherited from class org.orekit.attitudes.GroundPointing

getBodyFrame

Methods inherited from class java.lang.Object

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

Constructor Detail

GroundPointingWrapper

public GroundPointingWrapper(GroundPointing groundPointingLaw)

Creates a new instance.

Parameters:

groundPointingLaw - ground pointing attitude law without compensation

Method Detail

getGroundPointingLaw

public GroundPointing getGroundPointingLaw()

Get the attitude rotation.

Returns:

attitude satellite rotation from reference frame.

getTargetPoint

protected org.apache.commons.math.geometry.Vector3D getTargetPoint(Orbit orbit,
                                                                   Frame frame)
                                                            throws OrekitException

Compute the target point in specified frame.

Specified by:

getTargetPoint in class GroundPointing

Parameters:

orbit - orbit state

frame - frame in which observed ground point should be provided

Returns:

observed ground point position in specified frame

Throws:

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

getTargetPV

protected PVCoordinates getTargetPV(Orbit orbit,
                                    Frame frame)
                             throws OrekitException

Compute the target point position/velocity in specified frame.

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

Overrides:

getTargetPV in class GroundPointing

Parameters:

orbit - orbit state

frame - frame in which observed ground point should be provided

Returns:

observed ground point position/velocity in specified frame

Throws:

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

getBaseState

public Attitude getBaseState(Orbit orbit)
                      throws OrekitException

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

Parameters:

orbit - orbit state for which attitude is requested

Returns:

satellite base attitude state, i.e without compensation.

Throws:

OrekitException - if some specific error occurs

getAttitude

public Attitude getAttitude(Orbit orbit)
                     throws OrekitException

Compute the attitude corresponding to an orbital state.

Specified by:

getAttitude in interface AttitudeLaw

Overrides:

getAttitude in class GroundPointing

Parameters:

orbit - orbit state for which attitude is requested

Returns:

attitude attitude on the specified orbit, using orbit inertial frame as its reference frame

Throws:

OrekitException - if attitude cannot be computed

getCompensation

public abstract org.apache.commons.math.geometry.Rotation getCompensation(Orbit orbit,
                                                                          Attitude base)
                                                                   throws OrekitException

Compute the compensation rotation at given date.

Parameters:

orbit - orbit state for which compensation is requested

base - base satellite attitude in given frame.

Returns:

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

Throws:

OrekitException - if some specific error occurs