Package org.orekit.frames

Enum LOFType

java.lang.Object

java.lang.Enum<LOFType>

org.orekit.frames.LOFType

All Implemented Interfaces:

Serializable, Comparable<LOFType>, LOF

public enum LOFType
extends Enum<LOFType>
implements LOF

Enumerate for different types of Local Orbital Frames.

Author:

Luc Maisonobe, Maxime Journot, Vincent Cucchietti

Enum Constant Summary

Enum Constants

Enum Constant	Description
EQW	Constant for Equinoctial Coordinate System (X axis aligned with ascending node, Z axis aligned with orbital momentum).
LVLH	Constant for Local Vertical, Local Horizontal frame (X axis aligned with position, Z axis aligned with orbital momentum).
LVLH_CCSDS	Constant for Local Vertical, Local Horizontal frame as defined by CCSDS (Z axis aligned with opposite of position, Y axis aligned with opposite of orbital momentum).
LVLH_CCSDS_INERTIAL	Constant for Local Vertical, Local Horizontal frame as defined by CCSDS considered inertial (Z axis aligned with opposite of position, Y axis aligned with opposite of orbital momentum).
LVLH_INERTIAL	Constant for Local Vertical, Local Horizontal frame considered inertial (X axis aligned with position, Z axis aligned with orbital momentum).
NTW	Constant for Transverse Velocity Normal coordinate system (Y axis aligned with velocity, Z axis aligned with orbital momentum).
NTW_INERTIAL	Constant for Transverse Velocity Normal coordinate system considered inertial (Y axis aligned with velocity, Z axis aligned with orbital momentum).
QSW	Constant for QSW frame (X axis aligned with position, Z axis aligned with orbital momentum).
QSW_INERTIAL	Constant for QSW frame considered inertial (X axis aligned with position, Z axis aligned with orbital momentum).
TNW	Constant for TNW frame (X axis aligned with velocity, Z axis aligned with orbital momentum).
TNW_INERTIAL	Constant for TNW frame considered inertial (X axis aligned with velocity, Z axis aligned with orbital momentum).
VNC	Constant for Velocity - Normal - Co-normal frame (X axis aligned with velocity, Y axis aligned with orbital momentum).
VNC_INERTIAL	Constant for Velocity - Normal - Co-normal frame considered inertial (X axis aligned with velocity, Y axis aligned with orbital momentum).
VVLH	Constant for Vehicle Velocity, Local Horizontal frame (Z axis aligned with opposite of position, Y axis aligned with opposite of orbital momentum).
VVLH_INERTIAL	Constant for Vehicle Velocity, Local Horizontal frame considered inertial (Z axis aligned with opposite of position, Y axis aligned with opposite of orbital momentum).

Method Summary

Modifier and Type	Method	Description
String	getName()	Get name of the local orbital frame.
<T extends CalculusFieldElement<T>> FieldRotation<T>	rotationFromInertial(Field<T> field, FieldAbsoluteDate<T> date, FieldPVCoordinates<T> pv)	Get the rotation from inertial frame to local orbital frame.
abstract <T extends CalculusFieldElement<T>> FieldRotation<T>	rotationFromInertial(Field<T> field, FieldPVCoordinates<T> pv)	Get the rotation from inertial frame to local orbital frame.
Rotation	rotationFromInertial(AbsoluteDate date, PVCoordinates pv)	Get the rotation from inertial frame to local orbital frame.
abstract Rotation	rotationFromInertial(PVCoordinates pv)	Get the rotation from inertial frame to local orbital frame.
<T extends CalculusFieldElement<T>> FieldRotation<T>	rotationFromLOF(Field<T> field, LOFType fromLOF, FieldPVCoordinates<T> pv)	Get the rotation from input local orbital frame to the instance.
Rotation	rotationFromLOF(LOFType fromLOF, PVCoordinates pv)	Get the rotation from input local orbital frame to the instance.
abstract OrbitRelativeFrame	toOrbitRelativeFrame()	Convert current local orbital frame to CCSDS equivalent orbit relative frame when possible, null otherwise.
static LOFType	valueOf(String name)	Returns the enum constant of this type with the specified name.
static LOFType[]	values()	Returns an array containing the constants of this enum type, in the order they are declared.

Methods inherited from class java.lang.Enum

clone, compareTo, equals, finalize, getDeclaringClass, hashCode, name, ordinal, toString, valueOf

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.orekit.frames.LOF

isQuasiInertial, rotationFromLOF, rotationFromLOF, transformFromInertial, transformFromInertial, transformFromLOF, transformFromLOF

Enum Constant Detail

TNW

public static final LOFType TNW

Constant for TNW frame (X axis aligned with velocity, Z axis aligned with orbital momentum).

The axes of this frame are parallel to the axes of the VNC and NTW frames:

• X_TNW = X_VNC = Y_NTW
• Y_TNW = -Z_VNC = -X_NTW
• Z_TNW = Y_VNC = Z_NTW

See Also:

VNC, NTW

TNW_INERTIAL

public static final LOFType TNW_INERTIAL

Constant for TNW frame considered inertial (X axis aligned with velocity, Z axis aligned with orbital momentum).

The axes of this frame are parallel to the axes of the VNC and NTW frames:

• X_TNW = X_VNC = Y_NTW
• Y_TNW = -Z_VNC = -X_NTW
• Z_TNW = Y_VNC = Z_NTW

See Also:

VNC, NTW

QSW

public static final LOFType QSW

Constant for QSW frame (X axis aligned with position, Z axis aligned with orbital momentum).

This frame is also known as the LVLH frame, both constants are equivalent.

The axes of these frames are parallel to the axes of the VVLH frame:

• X_QSW/LVLH = -Z_VVLH
• Y_QSW/LVLH = X_VVLH
• Z_QSW/LVLH = -Y_VVLH

See Also:

LVLH, VVLH

QSW_INERTIAL

public static final LOFType QSW_INERTIAL

Constant for QSW frame considered inertial (X axis aligned with position, Z axis aligned with orbital momentum).

This frame is also known as the LVLH frame, both constants are equivalent.

The axes of these frames are parallel to the axes of the VVLH frame:

• X_QSW/LVLH = -Z_VVLH
• Y_QSW/LVLH = X_VVLH
• Z_QSW/LVLH = -Y_VVLH

See Also:

LVLH, VVLH

LVLH

public static final LOFType LVLH

Constant for Local Vertical, Local Horizontal frame (X axis aligned with position, Z axis aligned with orbital momentum).

BEWARE! Depending on the background (software used, textbook, community), different incompatible definitions for LVLH are used. This one is consistent with Vallado's book and with AGI's STK. However CCSDS standard, Wertz, and a.i. solutions' FreeFlyer use another definition (see LVLH_CCSDS).

This frame is also known as the QSW frame, both constants are equivalent.

The axes of these frames are parallel to the axes of the LVLH_CCSDS frame:

• X_LVLH/QSW = -Z_{LVLH_CCSDS}
• Y_LVLH/QSW = X_{LVLH_CCSDS}
• Z_LVLH/QSW = -Y_{LVLH_CCSDS}

See Also:

QSW, VVLH

LVLH_INERTIAL

public static final LOFType LVLH_INERTIAL

Constant for Local Vertical, Local Horizontal frame considered inertial (X axis aligned with position, Z axis aligned with orbital momentum).

BEWARE! Depending on the background (software used, textbook, community), different incompatible definitions for LVLH are used. This one is consistent with Vallado's book and with AGI's STK. However CCSDS standard, Wertz, and a.i. solutions' FreeFlyer use another definition (see LVLH_CCSDS).

This frame is also known as the QSW frame, both constants are equivalent.

The axes of these frames are parallel to the axes of the LVLH_CCSDS frame:

• X_LVLH/QSW = -Z_{LVLH_CCSDS}
• Y_LVLH/QSW = X_{LVLH_CCSDS}
• Z_LVLH/QSW = -Y_{LVLH_CCSDS}

See Also:

QSW, VVLH

LVLH_CCSDS

public static final LOFType LVLH_CCSDS

Constant for Local Vertical, Local Horizontal frame as defined by CCSDS (Z axis aligned with opposite of position, Y axis aligned with opposite of orbital momentum).

BEWARE! Depending on the background (software used, textbook, community), different incompatible definitions for LVLH are used. This one is consistent with CCSDS standard, Wertz, and a.i. solutions' FreeFlyer. However Vallado's book and with AGI's STK use another definition (see LVLH).

The axes of this frame are parallel to the axes of both the QSW and LVLH frames:

• X_{LVLH_CCSDS/VVLH} = Y_QSW/LVLH
• Y_{LVLH_CCSDS/VVLH} = -Z_QSW/LVLH
• Z_{LVLH_CCSDS/VVLH} = -X_QSW/LVLH

Since:

11.0

See Also:

QSW, LVLH

LVLH_CCSDS_INERTIAL

public static final LOFType LVLH_CCSDS_INERTIAL

Constant for Local Vertical, Local Horizontal frame as defined by CCSDS considered inertial (Z axis aligned with opposite of position, Y axis aligned with opposite of orbital momentum).

BEWARE! Depending on the background (software used, textbook, community), different incompatible definitions for LVLH are used. This one is consistent with CCSDS standard, Wertz, and a.i. solutions' FreeFlyer. However Vallado's book and with AGI's STK use another definition (see LVLH).

The axes of this frame are parallel to the axes of both the QSW and LVLH frames:

• X_{LVLH_CCSDS/VVLH} = Y_QSW/LVLH
• Y_{LVLH_CCSDS/VVLH} = -Z_QSW/LVLH
• Z_{LVLH_CCSDS/VVLH} = -X_QSW/LVLH

Since:

11.0

See Also:

QSW, LVLH

VVLH

public static final LOFType VVLH

Constant for Vehicle Velocity, Local Horizontal frame (Z axis aligned with opposite of position, Y axis aligned with opposite of orbital momentum).

This is another name for LVLH_CCSDS, kept here for compatibility with STK.

Beware that the name is misleading: in the general case (i.e. not perfectly circular), none of the axes is perfectly aligned with velocity! The preferred name for this should be LVLH_CCSDS.

The axes of this frame are parallel to the axes of both the QSW and LVLH frames:

• X_{LVLH_CCSDS/VVLH} = Y_QSW/LVLH
• Y_{LVLH_CCSDS/VVLH} = -Z_QSW/LVLH
• Z_{LVLH_CCSDS/VVLH} = -X_QSW/LVLH

See Also:

LVLH_CCSDS

VVLH_INERTIAL

public static final LOFType VVLH_INERTIAL

Constant for Vehicle Velocity, Local Horizontal frame considered inertial (Z axis aligned with opposite of position, Y axis aligned with opposite of orbital momentum).

This is another name for LVLH_CCSDS, kept here for compatibility with STK.

Beware that the name is misleading: in the general case (i.e. not perfectly circular), none of the axes is perfectly aligned with velocity! The preferred name for this should be LVLH_CCSDS.

The axes of this frame are parallel to the axes of both the QSW and LVLH frames:

• X_{LVLH_CCSDS/VVLH} = Y_QSW/LVLH
• Y_{LVLH_CCSDS/VVLH} = -Z_QSW/LVLH
• Z_{LVLH_CCSDS/VVLH} = -X_QSW/LVLH

See Also:

LVLH_CCSDS

VNC

public static final LOFType VNC

Constant for Velocity - Normal - Co-normal frame (X axis aligned with velocity, Y axis aligned with orbital momentum).

The axes of this frame are parallel to the axes of the TNW and NTW frames:

• X_VNC = X_TNW = Y_NTW
• Y_VNC = Z_TNW = Z_NTW
• Z_VNC = -Y_TNW = X_NTW

See Also:

TNW, NTW

VNC_INERTIAL

public static final LOFType VNC_INERTIAL

Constant for Velocity - Normal - Co-normal frame considered inertial (X axis aligned with velocity, Y axis aligned with orbital momentum).

The axes of this frame are parallel to the axes of the TNW and NTW frames:

• X_VNC = X_TNW = Y_NTW
• Y_VNC = Z_TNW = Z_NTW
• Z_VNC = -Y_TNW = X_NTW

See Also:

TNW, NTW

EQW

public static final LOFType EQW

Constant for Equinoctial Coordinate System (X axis aligned with ascending node, Z axis aligned with orbital momentum).

Since:

11.0

NTW

public static final LOFType NTW

Constant for Transverse Velocity Normal coordinate system (Y axis aligned with velocity, Z axis aligned with orbital momentum).

The axes of this frame are parallel to the axes of the TNW and VNC frames:

• X_NTW = -Y_TNW = Z_VNC
• Y_NTW = X_TNW = X_VNC
• Z_NTW = Z_TNW = Y_VNC

Since:

11.0

See Also:

TNW, VNC

NTW_INERTIAL

public static final LOFType NTW_INERTIAL

Constant for Transverse Velocity Normal coordinate system considered inertial (Y axis aligned with velocity, Z axis aligned with orbital momentum).

The axes of this frame are parallel to the axes of the TNW and VNC frames:

• X_NTW = -Y_TNW = Z_VNC
• Y_NTW = X_TNW = X_VNC
• Z_NTW = Z_TNW = Y_VNC

Since:

11.0

See Also:

TNW, VNC

Method Detail

values

public static LOFType[] values()

Returns an array containing the constants of this enum type, in the order they are declared. This method may be used to iterate over the constants as follows:

for (LOFType c : LOFType.values())
    System.out.println(c);

Returns:

an array containing the constants of this enum type, in the order they are declared

valueOf

public static LOFType valueOf(String name)

Returns the enum constant of this type with the specified name. The string must match exactly an identifier used to declare an enum constant in this type. (Extraneous whitespace characters are not permitted.)

Parameters:

name - the name of the enum constant to be returned.

Returns:

the enum constant with the specified name

Throws:

IllegalArgumentException - if this enum type has no constant with the specified name

NullPointerException - if the argument is null

getName

public String getName()

Get name of the local orbital frame.

Specified by:

getName in interface LOF

Returns:

name of the local orbital frame

rotationFromLOF

public Rotation rotationFromLOF(LOFType fromLOF,
                                PVCoordinates pv)

Get the rotation from input local orbital frame to the instance.

This rotation does not include any time derivatives. If first time derivatives (i.e. rotation rate) is needed as well, the full LOF.transformFromLOF(LOF, AbsoluteDate, PVCoordinates) method must be called and the complete rotation transform must be extracted from it.

Parameters:

fromLOF - input local orbital frame

pv - position-velocity of the spacecraft in some inertial frame

Returns:

rotation from input local orbital frame to the instance

rotationFromLOF

public <T extends CalculusFieldElement<T>> FieldRotation<T> rotationFromLOF(Field<T> field,
                                                                            LOFType fromLOF,
                                                                            FieldPVCoordinates<T> pv)

Get the rotation from input local orbital frame to the instance.

This rotation does not include any time derivatives. If first time derivatives (i.e. rotation rate) is needed as well, the full LOF.transformFromLOF(LOF, FieldAbsoluteDate, FieldPVCoordinates) method must be called and the complete rotation transform must be extracted from it.

Type Parameters:

T - type of the field elements

Parameters:

field - field to which the elements belong

fromLOF - input local orbital frame

pv - position-velocity of the spacecraft in some inertial frame

Returns:

rotation from input local orbital frame to the instance

rotationFromInertial

public Rotation rotationFromInertial(AbsoluteDate date,
                                     PVCoordinates pv)

Get the rotation from inertial frame to local orbital frame.

This rotation does not include any time derivatives. If first time derivatives (i.e. rotation rate) is needed as well, the full transformFromInertial method must be called and the complete rotation transform must be extracted from it. It is unnecessary to use this method when dealing with LOFType, use rotationFromInertial(PVCoordinates) instead.

Specified by:

rotationFromInertial in interface LOF

Parameters:

date - date of the rotation

pv - position-velocity of the spacecraft in some inertial frame

Returns:

rotation from inertial frame to local orbital frame

rotationFromInertial

public abstract Rotation rotationFromInertial(PVCoordinates pv)

Get the rotation from inertial frame to local orbital frame.

This rotation does not include any time derivatives. If first time derivatives (i.e. rotation rate) is needed as well, the full LOF.transformFromInertial(AbsoluteDate, PVCoordinates) method must be called and the complete rotation transform must be extracted from it.

Parameters:

pv - position-velocity of the spacecraft in some inertial frame

Returns:

rotation from inertial frame to local orbital frame

rotationFromInertial

public <T extends CalculusFieldElement<T>> FieldRotation<T> rotationFromInertial(Field<T> field,
                                                                                 FieldAbsoluteDate<T> date,
                                                                                 FieldPVCoordinates<T> pv)

Get the rotation from inertial frame to local orbital frame.

This rotation does not include any time derivatives. If first time derivatives (i.e. rotation rate) is needed as well, the full LOF.transformFromInertial(FieldAbsoluteDate, FieldPVCoordinates) method must be called and the complete rotation transform must be extracted from it.

It is unnecessary to use this method when dealing with LOFType, use rotationFromInertial(Field, FieldPVCoordinates) instead.

Specified by:

rotationFromInertial in interface LOF

Type Parameters:

T - type of the field elements

Parameters:

field - field to which the elements belong

date - date of the rotation

pv - position-velocity of the spacecraft in some inertial frame

Returns:

rotation from inertial frame to local orbital frame

rotationFromInertial

public abstract <T extends CalculusFieldElement<T>> FieldRotation<T> rotationFromInertial(Field<T> field,
                                                                                          FieldPVCoordinates<T> pv)

Get the rotation from inertial frame to local orbital frame.

This rotation does not include any time derivatives. If first time derivatives (i.e. rotation rate) is needed as well, the full LOF.transformFromInertial(FieldAbsoluteDate, FieldPVCoordinates) method must be called and the complete rotation transform must be extracted from it.

Type Parameters:

T - type of the field elements

Parameters:

field - field to which the elements belong

pv - position-velocity of the spacecraft in some inertial frame

Returns:

rotation from inertial frame to local orbital frame

toOrbitRelativeFrame

public abstract OrbitRelativeFrame toOrbitRelativeFrame()

Convert current local orbital frame to CCSDS equivalent orbit relative frame when possible, null otherwise.

Returns:

CCSDS equivalent orbit relative frame when possible, null otherwise

See Also:

OrbitRelativeFrame