org.orekit.attitudes
Class AbstractSlew

java.lang.Object
  org.orekit.attitudes.AbstractSlew

All Implemented Interfaces:

Serializable, AttitudeLeg, AttitudeProvider, Slew

Direct Known Subclasses:

AbstractIsisSpinBiasSlew, ConstantSpinSlew, TwoSpinBiasSlew

public abstract class AbstractSlew
extends Object
implements Slew

This abstract class is the basic implementation of the Slew interface.
It does not include the algorithm computing the maneuver, as this depends on the type of slew and thus is implemented by the classes extending this abstract class.

A generic slew maneuver is represented by the following variables:

• the interval of validity t0-t1 of the maneuver;
• the attitude law before t0;
• the attitude law after t1;

Since:

1.1

Version:

$Id: AbstractSlew.java 17582 2017-05-10 12:58:16Z bignon $

Author:

Tiziana Sabatini

See Also:

Slew, Serialized Form

Field Summary

protected boolean	computed True if the slew has already been computed.
protected PVCoordinatesProvider	currentProvider The PV coordinates provider that has been used to compute the maneuver.
protected AttitudeProvider	fLaw The attitude law after the slew.
protected AttitudeProvider	iLaw The attitude law before the slew.
protected AbsoluteDateInterval	intervalOfValidity Interval of validity of the maneuver (with closed endpoints).

Constructor Summary

AbstractSlew(AttitudeProvider initialLaw, AttitudeProvider finalLaw, AbsoluteDate initialDate, AbsoluteDate finalDate)
Builds a slew when its interval of validity is known.

Method Summary

Attitude	getAttitude(Orbit orbit) Compute the attitude corresponding to an orbital state.
Attitude	getAttitude(PVCoordinatesProvider pvProv, AbsoluteDate date, Frame frame) Compute the attitude corresponding to an orbital state.
double	getDuration()
AbsoluteDateInterval	getTimeInterval() Return the time interval of validity

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.orekit.attitudes.Slew

compute, getAttitude

Methods inherited from interface org.orekit.attitudes.AttitudeProvider

setSpinDerivativesComputation

Field Detail

iLaw

protected final AttitudeProvider iLaw

The attitude law before the slew.

fLaw

protected final AttitudeProvider fLaw

The attitude law after the slew.

intervalOfValidity

protected AbsoluteDateInterval intervalOfValidity

Interval of validity of the maneuver (with closed endpoints).

computed

protected boolean computed

True if the slew has already been computed.

currentProvider

protected PVCoordinatesProvider currentProvider

The PV coordinates provider that has been used to compute the maneuver.

Constructor Detail

AbstractSlew

public AbstractSlew(AttitudeProvider initialLaw,
                    AttitudeProvider finalLaw,
                    AbsoluteDate initialDate,
                    AbsoluteDate finalDate)

Builds a slew when its interval of validity is known.

Parameters:

initialLaw - the AttitudeProvider representing the attitude law before the slew

finalLaw - the AttitudeProvider representing the attitude law after the slew

initialDate - the initial date of the interval of validity

finalDate - the final date of the interval of validity

Method Detail

getAttitude

public Attitude getAttitude(PVCoordinatesProvider pvProv,
                            AbsoluteDate date,
                            Frame frame)
                     throws OrekitException

Description copied from interface: AttitudeProvider

Compute the attitude corresponding to an orbital state.

Specified by:

getAttitude in interface AttitudeProvider

Parameters:

pvProv - local position-velocity provider around current date

date - current date

frame - reference frame from which attitude is computed

Returns:

attitude attitude on the specified date and position-velocity state

Throws:

OrekitException - if attitude cannot be computed

getAttitude

public Attitude getAttitude(Orbit orbit)
                     throws OrekitException

Compute the attitude corresponding to an orbital state.

Specified by:

getAttitude in interface AttitudeProvider

Parameters:

orbit - current orbit

Returns:

attitude attitude on the current orbit

Throws:

OrekitException - if attitude cannot be computed

getTimeInterval

public final AbsoluteDateInterval getTimeInterval()
                                           throws OrekitException

Description copied from interface: AttitudeLeg

Return the time interval of validity

Specified by:

getTimeInterval in interface AttitudeLeg

Returns:

time interval of validity

Throws:

OrekitException - if the time interval is not computed (for a slew)

getDuration

public final double getDuration()
                         throws OrekitException

Returns:

the duration of the time interval of validity of the slew.

Throws:

OrekitException - if the time interval is not computed